bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring the water, sanitation and hygiene status and health outcomes in Zimbabwe: a scoping review protocol
Authors: Betera Same , Wispriyono Bambang , Nunu Wilfred Njabulo
Published: August 2024

Background

The sixth United Nations Sustainable Development Goal emphasises universal access to clean water, sanitation and hygiene (WASH) to ensure human well-being as a fundamental human right for sustainable development. In Zimbabwe, WASH reforms began more than a century ago from the preindependence to postindependence era. However, countries face pressing challenges in improving their related health outcomes. Therefore, this scoping review aims to explore WASH status and how it influences health outcomes in Zimbabwe.

Methods and analysis

The leading databases to be searched for relevant sources published in English with an unrestricted search back until May 2024 include PubMed, EBSCO, SAGE, SpringerLink, Cochrane Library, ScienceDirect, Scopus, Web of Science and African Journals Online. A search string was developed for retrieving literature, and reports from key stakeholders in the WASH sector will be included in this study as grey literature. The study will employ a two-step screening process for identifying relevant literature incorporating Cohen’s kappa coefficient statistics to estimate the inter-rater reliability between two independent reviewers using Mendeley and Rayyan software. The Strengthening the Reporting of Observational Studies in Epidemiology checklist for observational studies and the Consolidated Standards of Reporting Trials checklist for randomised controlled trials will be used for the quality checks. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews will guide this study in terms of data collection, extraction and analysis from relevant literature. Data charting was used to present and interpret the findings. The entire process is scheduled to commence in June 2024, with the manuscript anticipated to be submitted to a journal in October 2024.

Ethics and dissemination

This review will use only published data; therefore, no ethical clearance is required. The findings will be disseminated to relevant stakeholders through peer-reviewed journals, meetings, conferences, seminars and forums.
Spatial-temporal analysis of climate and socioeconomic conditions on cholera incidence in Mozambique from 2000 to 2018: an ecological longitudinal retrospective study
Authors: Armando Chaibo Jose , Rocklöv Joacim , Sidat Mohsin , Tozan Yesim , Mavume Alberto Francisco , Bunker Aditi , Sewe Maquins Odhiambo
Published: August 2024

Objectives

This study aims to assess both socioeconomic and climatic factors of cholera morbidity in Mozambique considering both spatial and temporal dimensions.

Design

An ecological longitudinal retrospective study using monthly provincial cholera cases from Mozambican Ministry of Health between 2000 and 2018. The cholera cases were linked to socioeconomic data from Mozambique Demographic and Health Surveys conducted in the period 2000–2018 and climatic data; relative humidity (RH), mean temperature, precipitation and Normalised Difference Vegetation Index (NDVI). A negative binomial regression model in a Bayesian framework was used to model cholera incidence while adjusting for the spatiotemporal covariance, lagged effect of environmental factors and the socioeconomic indicators.

Setting

Eleven provinces in Mozambique.

Results

Over the 19-year period, a total of 153 941 cholera cases were notified to the surveillance system in Mozambique. Risk of cholera increased with higher monthly mean temperatures above 24°C in comparison to the reference mean temperature of 23°C. At mean temperature of 19°C, cholera risk was higher at a lag of 5–6 months. At a shorter lag of 1 month, precipitation of 223.3 mm resulted in an 57% increase in cholera risk (relative risk, RR 1.57 (95% CI 1.06 to 2.31)). Cholera risk was greatest at 3 lag months with monthly NDVI of 0.137 (RR 1.220 (95% CI 1.042 to 1.430)), compared with the reference value of 0.2. At an RH of 54%, cholera RR was increased by 62% (RR 1.620 (95% CI 1.124 to 2.342)) at a lag of 4 months. We found that ownership of radio RR 0.29, (95% CI 0.109 to 0.776) and mobile phones RR 0.262 (95% CI 0.097 to 0.711) were significantly associated with low cholera risk.

Conclusion

The derived lagged patterns can provide appropriate lead times in a climate-driven cholera early warning system that could contribute to the prevention and management of outbreaks.
Transition from rehabilitation hospital to the National Disability Insurance Scheme (NDIS) for people with brain injury and spinal cord injury: a data linkage protocol
Authors: Guthrie Simon Andrew John , Alexander Tara , Tickle Leonie , Winkler Di , Walsh John Ernest
Published: August 2024

Introduction

Traumatic brain injury (TBI) and spinal cord injury (SCI) are both major contributors to permanent disability globally, with an estimated 27 million new cases of TBI and 0.93 million new cases of SCI globally in 2016. In Australia, the National Disability Insurance Scheme (NDIS) provides support to people with disability. Reports from the NDIS suggest that the cost of support for people with TBI and SCI has been increasing dramatically, and there is a lack of independent analysis of the drivers of these increases. This data linkage seeks to better understand the participant transition between rehabilitation hospitals and the NDIS and the correlation between functional independence in rehabilitation and resource allocation in the NDIS.

Methods and analysis

This is a retrospective, population-based cohort study using Australia-wide NDIS participant data and rehabilitation hospital episode data. The linked dataset provides a comparison of functional independence against which to compare the NDIS resource allocation to people with TBI and SCI. This protocol outlines the secure and separated data linkage approach employed in linking partially identified episode data from the Australasian Rehabilitation Outcomes Centre (AROC) with identified participant data from the NDIS. The linkage employs a stepwise deterministic linkage approach. Statistical analysis of the linked dataset will consider the relationship between the functional independence measure score from the rehabilitation hospital and the committed funding supports in the NDIS plan. This protocol sets the foundation for an ongoing data linkage between rehabilitation hospitals and the NDIS to assist transition to the NDIS.

Ethics and dissemination

Ethics approval is from the Macquarie University Human Research Ethics Committee. AROC Data Governance Committee and NDIS Data Management Committee have approved this project. Research findings will be disseminated to key stakeholders through peer-reviewed publications in scientific journals and presentations to clinical and policy audiences via AROC and NDIS.
Efficacy of high-flow nasal oxygen therapy started in the emergency room versus conventional oxygen therapy in patients with acute hypoxaemic respiratory distress: protocol for a French multicentric, prospective, open and randomised superiority study protocol (HIFLOWED)
Authors: Pretalli Jean Baptiste , Parmentier Anne-Laure , Mauny Frederic , Desmettre Thibaut , Marjanovic Nicolas , Capellier Gilles , Khoury Abdo
Published: August 2024

Introduction

Acute respiratory failure is a life-threatening condition frequently found in the emergency department. High-flow nasal oxygen (HFNO) is increasingly used in emergency departments for patients with hypoxaemic acute respiratory failure. However, despite the increasing number of studies, its potential advantages regarding the need for therapeutic escalation and mortality have not been precisely evaluated. Our objective is to compare conventional oxygen therapy to HFNO when they are initiated during the first hour following the patient’s arrival at the emergency department, with the hypothesis that HFNO would reduce the need for ventilatory therapy escalation.

Methods and analysis

This is a multicentric, prospective, open and randomised superiority study. 500 inpatients will be randomised (1:1) to receive conventional oxygen therapy or HNFO. The primary outcome is a failure in the oxygen therapy defined as the need for a therapeutic escalation within 4 hours after therapy initiation.

Ethics and dissemination

The study has been submitted and approved by the Comité de Protection des Personnes Nord Ouest IV (20 October 2020). As required, a notification was sent to the Agence nationale de sécurité du médicament et des produits de santé (22 October 2020). The research results will be published in peer-reviewed publications and presented at international conferences.

Trial registration number

NCT04607967.
Assessment of the understanding and awareness of bioethics among healthcare professionals in all public and private hospitals of Haripur district, Pakistan: a multicentre cross-sectional study
Authors: Ateeb Muhammad , Haq Ijaz ul , Zakki Shahbaz Ahmad , Altaf Ehtisham , Junaid Muhammad , Ali Mustafa , Rehman Atif Ur , Wajid Daniyal , Fareed Abdullah , Mehmood Asad
Published: August 2024

Objective

To assess the level of bioethics awareness among healthcare professionals in Pakistan, focusing on the associations with sociodemographic characteristics, training and teaching of ethics, medical ethics practice and specific ethical issues.

Design

Cross-sectional study.

Setting

Public and private hospitals in Haripur, Pakistan.

Participants

A total of 647 healthcare professionals participated in this study.

Methods

This study was conducted between March and May 2023, following Strengthening the Reporting of Observational Studies in Epidemiology checklist criterion, involving healthcare professionals with at least 6 months of experience in patient care practice. Providers under close supervision are advised not to respond to the bioethics knowledge, attitudes and practices survey form due to potential ethical dilemmas.

Results

Both physicians and non-physicians need to know more about bioethics. There was a significant difference (p<0.05) in ethical training and teaching based on job categories/designations, with ethical views differing greatly by job designation. Specific ethical issues, such as accepting gifts from patients and pharmaceutical companies, referral fees, advising specific products, disclosure of medical errors, patient confidentiality, not informing patients fully about treatment and performing tasks for financial gain, showed significant associations (p<0.05) with healthcare professional’s designation. Ethical awareness scores also showed significant differences (p<0.05) based on age, ethnicity, place of posting, professional experience and the organisation’s ethical guidelines.

Conclusion

This study highlighted a notable gap in the understanding of certain ethical concerns among healthcare professionals, with nurses showing relatively lower awareness of healthcare practice compared with other professionals. Addressing these issues through targeted training and robust ethical guidelines is critical to improving patient care in Pakistan’s healthcare system.
Understanding how traumatic brain injury-related changes in fluid biomarkers affect quality of life outcomes in veterans: a prospective observational trial protocol (UNTANGLE)
Authors: Metry Youstina , McMullan Christel , Upthegrove Rachel , Belli Antonio , Gomes Renata S M , Blanch Richard J , Ahmed Zubair
Published: August 2024

Introduction

Traumatic brain injury (TBI) is a major cause of disability, with annual global incidence estimated as 69 million people. Survivors can experience long-term visual changes, altered mental state, neurological deficits and long-term effects that may be associated with mental illness. TBI is prevalent in military personnel due to gunshot wounds, and blast injury. This study aims to evaluate the relationship between evolving visual, biochemical and mental health changes in both military veterans and civilians, suffering from TBI, and detect preliminary indicators of prognosis for TBI recovery, and quality-of-life outcomes.

Methods and analysis

UNTANGLE is a 24-month prospective observational pilot study recruiting three patient groups: civilians with acute moderate-severe TBI, military veterans with diagnosis of a previous TBI and a control group of civilians or veterans with no history of a previous TBI. Patients will undergo visual, biochemical and mental health assessments, as well as patient-reported quality of life outcome measures over the course of a 1-year follow-up period.

Ethics and dissemination

Ethical approval has been obtained from the Health Research Authority and Health and Care Research Wales with a REC reference number of 23/NW/0203. The results of the study will be presented at scientific meetings and published in peer-reviewed journals, including both civilian and military-related publications. We will also present our findings at national and international meetings of learnt neuroscience and neuropsychiatry and military societies. We anticipate that our pilot study will inform a larger study on the long-term outcomes of TBI and quality of life, specific to military veterans, such that potential interventions may be accessed as quickly as possible.

Trial registration number

ISRCTN13276511.
Psychiatrists’ experiences of involuntary care in South Africa: dilemmas for practice in challenging contexts
Authors: Freeman Alex Morung , Asmal Laila , Swartz Leslie
Published: August 2024

Providing for people with psychosocial conditions in crisis is a complex and controversial endeavour that has gained significant attention over the past decade. This increased focus is driven by global calls to reduce coercion, including by the United Nations Committee on the Rights of Persons with Disabilities, who interpret Article 12 of the United Nations Convention on the Rights of Persons with Disabilities in General Comment 1 to advocate for the replacement of substituted decision-making with supported decision-making. Psychiatrists occupy a central role in determining how to care for and respond to individuals with psychosocial conditions in crisis in the midst of these debates. They must protect the rights of people with psychosocial conditions in crisis and provide appropriate support within challenging and dynamic contexts. This responsibility includes promoting the autonomy of people with psychosocial condition while ensuring their long-term health, safety and well-being.

In this study, we conducted a phenomenological analysis with a sample of nine psychiatrists in South Africa to explore their experiences with involuntary care and the complex dilemmas they face in delivering healthcare to individuals with mental health conditions. Our findings indicate that psychiatrists encounter significant challenges in preserving patient autonomy, particularly within the resource-limited context of South Africa. Pervasive stigma and insufficient support infrastructure complicate efforts to prioritise autonomy. At the same time, professionals must address the critical need to ensure the long-term safety and well-being of their patients. The absence of involuntary care can exacerbate a person’s vulnerability to community stigma and inadequate community support, posing severe risks to their welfare. Balancing between protecting a person’s autonomy and addressing the limitations of support structures creates a complex predicament for mental health professionals, often resulting in feelings of isolation and moral distress among psychiatrists.
Edge state regulation and interfacial design on spin transport properties of VC2-based nanoscale devices
Authors: Li Haoran , Zhang Bei , Qiu Yifeng
Published: August 2024

Edge state and interfacial design are efficient strategies to regulate the spin-transport properties of nanoscale devices. Spin-polarized transport properties of VC2 nanoribbon device and poly-(terphenylene-butadiynylene) PTB molecular junctions are studied by using density functional theory (DFT) and non-equilibrium Green function. Results show good self-selected filtering properties for spin-up current are highly suppressed, where there is only spin-down current that can propagate through the scattering region of such a nanoribbon device. What needs to be pointed out is that spin-down current exhibits an obvious negative differential resistance effect. Current and transmission spectrum peaks are significantly weakened, and the negative differential resistance effect disappears after a PTB molecule is embedded between two semi-infinite VC2 nanoribbon electrodes. This work provides a basis for improving the design and method of spintronic devices.
Thermal analysis of Yeleswarapu mucus flowing through a complex micro-passage formed by tips of beating cilia
Authors: Ashfaq Muhammad , Asghar Zeeshan , Nie Yufeng , Gondal Muhammad Asif
Published: August 2024

Motile cilia are hair-like, tiny structures that originate in different types of biological processes. Yeleswarapu fluid model is approximated as non-Newtonian mucus, which is viscous and slippery fluid with key roles in lubrication, protection, and particle trapping in the respiratory and digestive systems. The properties of Yeleswarapu fluid with heat transfer in ciliated channels are investigated in this study. The fluid flow is characterized as laminar (low Reynold number) and incompressible (constant density) in a two-dimensional complex wavy channel generated via metachronal waves of cilia. A static frame of reference is first transformed into a dynamic frame of reference. Afterward, the system of governing equations is transformed into a non-dimensional form by using scaling factors. The half-width of the channel is substantially smaller than the wavelength of metachronal waves. Hence, the constitutive equations are simplified by the long wavelength hypothesis. The perturbation approach is employed to solve the simplified system of differential equations. This research investigates how different boundary walls and rheology affect fluid flow. Additionally, graphs of the streamlines, velocity field, temperature, heat transfer coefficient, and pressure rise are included.
(Invited) Emergent Chiroptical Properties in Assembled Molecules and Materials: From Native Chirality to Global Chirality
Authors: Thomas K. George
Published: August 2024

The emergence of chiroptical properties in molecules and materials through their asymmetric organizations has fascinated humankind in general and the scientific community in particular. By adopting molecules, plasmonic systems, and semiconductor quantum dots as examples, the translation of ‘local’ chirality in these building blocks to the ‘global’ chirality when they self-assemble as nanoobjects will be explained. The presentation covers the following aspects.

In assembled molecular systems, induced circular dichroism (ICD) originates through the off-resonance coupling of transition dipoles, resulting in monosignated CD signals. In contrast, exciton-coupled circular dichroism (EC-CD) originates through the on-resonance exciton coupling, displaying bisignated CD signals.1-3 Bisignation in the CD responses of assembled plasmonic systems results from the resonant plasmon coupling, termed surface plasmon-coupled circular dichroism (SP-CD).4,5

The presentation will draw parallels between the emergence of EC-CD and SP-CD based on the coupling of their transition dipoles.3 More importantly, our studies have concluded that the sign of the EC-CD/SP-CD depends not only on the handedness of the assembly but also on the sign of the interaction energy between the neighboring dipoles.6

The presentation will also discuss how chiral surface domains of various self-assembled amino acid-based templates transfer chiral information to bound achiral chromophores. The origin of CD and CPL of achiral molecules on these templates are explained based on exciton coupling.7

The presentation will also provide fundamental insight into the interaction of chiral molecules with silicon nanoparticles and the emergence of its CD and CPL.8

An open challenge is to develop a universal model which can explain the chiroptical properties of assembled systems based on the transition dipolar coupling and interaction energy: our findings in this direction will be presented.

Thomas R, Kumar J, George J, et al. Phys. Chem. Lett., 2018, 9, 919-932.

Kar S, Swathi K, Sissa C, et al., Phys. Chem. Lett., 2018, 9, 4584-4590.

Nizar NSS, Sujith M, Swathi K, et al. Soc. Rev.,2021,
50

,
11208-11226.

George J, Thomas KG, J.
Am. Chem. Soc.
2010, 132, 2502-2503.

George J, Kar S, Anupriya ES, et al. ACS Nano
13, 2019, 4392-4401.

Swathi K, Sissa C, Painelli A, et al. Commun.
,

2020
, 56, 8281-8284.

Somasundaran SM, Kompella SVK, Mohan TMN, et al. ACS Nano 2023

17, 11054-11069.

Sujith M, Vishnu EK, Sappati S, et al. J. Am. Chem. Soc.
, 2022, 144, 5074-5086.

The theoretical collaborations with Dr. R. S. Swathi, IISER Thiruvananthapuram (India), Dr. Cristina Sissa and Prof. Anna Painelli, University of Parma (Italy), and Prof. S. Balasubramanian, JNCASR, Bangalore are greatly acknowledged. KGT acknowledges the J. C. Bose National Fellowship and Nanomission project (DST/NM/TUE/EE-01/2019), the Department of Science and Technology, Government of India, for financial support.
Solvation-Property Relationship of Lithium-Sulfur Battery Electrolytes Probed via Potentiometric Measurements
Authors: Kim Sang Cheol , Cui Yi
Published: August 2024

The Li-S battery is a promising next-generation battery chemistry that offers high energy density and low cost. Li-S battery has a unique chemistry with intermediate sulfur species readily solvated in electrolytes, and understanding their implications is important from both practical and fundamental perspectives. However, the nature of the solvated sulfur species, their interactions and their impact on the battery remains elusive, in part due to the paucity of techniques. Recently, our group developed a potentiometric technique to probe the solvation free energy of electrolytes. In this study, we utilize the technique to formulate solvation-property relationships in various electrolytes and investigate its impact on the solvated lithium polysulides (LiPS). We find that solvation free energy impacts Li-S battery voltage profile, LiPS solubility, Li-S battery cyclability and the Li metal anode, which are all critical to the battery's performance. Weaker solvation leads to a lower 1st plateau voltage, higher 2nd plateau voltage, lower LiPS solubility, and superior cyclability of Li-S full cell and Li metal anode. We explore the mechanisms behind these observed phenomena and discuss the implications for the design of high-performance electrolytes for Li-S batteries.
Tailoring Multi-Metallic Phosphide Heterostructures for High Energy Density Hybrid Supercapacitors
Authors: Adhikari Sangeeta , NOH Gihyeok , Kim Do-Heyoung
Published: August 2024

Transition metal phosphides have emerged as a cost effective and resourceful materials that gained extreme attention in the energy sector due to deliverance of high capacitance as well as good redox ability comparable with other oxide materials, which makes them budding material for next-generation electrochemical energy storage (EES) systems. Thanks to the metal-phosphorous chelate in the structure which probes the storage mechanism in EES systems. The electrochemical performance can be enhanced by combining multi-metals in the phosphide to collectively utilize the individual features which will increase the charge efficiency. Herein, tri-metallic Ni-Co-Mo-P electrode on Ni-foam substrate was prepared using simplified hydrothermal-calcination-phosphorylation process. The introduction of Mo enhances the electronic conductivity in the trimetallic phosphide electrode which is reflected in the increased electrochemical performance in comparison to NiCoP electrode. Although, Ni-Co-Mo-P electrode delivers superior activity compared to oxide and precursor electrode, however, the capacity retention till 10 A/g was observed to be 60%, which is higher than other prepared electrodes. The enhanced charge storage performance can be attributed to increased number of electrochemical surface area facilitating more redox reactions. The asymmetric supercapacitor device is constructed with Ni-Co-Mo-P // rGO that delivered high energy and power density with satisfactory cyclic capability.
Deep Learning Based 3D Resolution Recovery for Breakthrough Imaging of Electrochemical Energy Devices
Authors: Kelly Stephen T , Trenikhina Yulia , Johnson Nathan , Harris William
Published: August 2024

Many energy materials can only be understood within the context of the (often sealed) devices they make up. Batteries and fuel cells contain intricate mixtures of materials with features and arrangements that span across many orders of magnitude in size and operate under non-ambient conditions. In these devices, the microstructures of the constituent materials and how they are arranged with respect to each other is directly linked to the device performance and degradation behaviors. Complicating matters, opening the devices for inspection and analysis can irreversibly alter the very microstructures in question and can pose safety hazards to researchers if not done correctly. Furthermore, critical material and device properties such as tortuosity or ion transport pathways can only be accurately quantified in 3D. As such, observing microstructures and their evolution in 3D and in their native state is essential for developing a robust understanding of how to engineer new battery and fuel cell materials and architectures with improved performance.

X-ray microscopy (XRM) provides a unique method for observing these microstructures in 3D at high resolutions without needing to open them. However, microscopy techniques like XRM make tradeoffs between FOV and resolution, which can pose challenges for strongly multiscale systems like batteries and fuel cells. For example, if images are acquired at high enough resolution to observe critical features like electrode particle sizes in lithium-ion batteries or gas diffusion layer fiber weaves, catalyst distributions, and microporous layer cracks in polymer electrolyte fuel cells, the field of view of that image is restricted to a small local region of the sample. This means that broader defect distributions or larger scale inhomogeneities will be missed. Additionally, for quantitative analysis applications, this means that statistical relevance will be sacrificed because of the limited analysis volume at the appropriate resolution. And for computational modelling efforts, device level phenomena will not be captured well due to the restricted field of view.

Advances in modern AI-based resolution recovery methods combined with the non-destructive multiscale imaging capabilities of X-ray microscopy have allowed researchers to overcome this dependency between resolution and field of view to produce 3D images with both high resolution and large field of view. We present here examples of applying these methods to applications in lithium-ion battery and polymer electrolyte fuel cell research [1].

[1] Wang, Y.D., Meyer, Q., Tang, K. et al. Large-scale physically accurate modelling of real proton exchange membrane fuel cell with deep learning. Nat Commun 14, 745 (2023).
Multi-Stage Engineered Co-Free Li[Ni1-X-Y
Ti
x
Al
y
]O2 Cathode for High-Energy Li-Ion Batteries
Authors: Park Geon-Tae , Yoon Jung-In , Sun Yang-Kook
Published: August 2024

Since the global blueprint for carbon net zero emissions has been drawn, a part of the internal combustion engine (ICE) market share of vehicles has been continually shifting toward electric powered public and personal transportation. However, the serious remaining challenges regarding the price and performance issues of lithium-ion batteries (LIBs), which are the primary power source for electric vehicles (EVs), have impeded the large-scale adoption of EVs. Solving the affordability issue of current layered cathodes requires reducing the reliance on Co, which is extremely expensive with supply uncertainty. The aim of developing Co-poor or Co-free cathodes has led to an interest in LiNiO2 (LNO).1 LNO is one of the most promising cost-effective Co-free cathodes for LIBs because the cathode can achieve a high specific capacity of over 250 mAh g-1 with a typical upper voltage of 4.3 V versus Li/Li+. However, its poor cycling durability and thermal instability make its practical use difficult.2 In this study, we propose a highly stable Co-free Ni-enriched layered cathode based on LNO through a new doping strategy that incorporates heteroelements at different doping stages, i.e., the introduction of Ti during Ni(OH)2 synthesis and doping excess amounts of Al during the lithiation step. In combination with cathode surface protection, i.e., electrolyte modification or cathode surface coating, the proposed cathode retains 72.0% of its initial capacity after 3,500 cycles, which is the state-of-the-art for Co-free layered cathodes.

Reference
s
:

[1] M. Bianchini, M. Roca-Ayats, P. Hartmann, T. Brezesinski, J. Janek, Angew. Chem. Int. Ed., 58 (2019) 10434-10458.

[2] H.-J. Noh, S. Youn, C.S. Yoon, Y.-K. Sun, J. Power Sources, 233 (2013) 121-130.
Improved Structural and Electrochemical Properties of Mg-Doped Nickel Cobaltite Nanoparticles Synthesized Using Low-Temperature Microwave Hydrothermal Method
Authors: Neelam Sathyanarayana , Chidurala Shilpa Chakra , Katlakunta Sadhana , Lal Babu , Baddam Sudhakar Reddy , Butreddy Ravinder Reddy
Published: August 2024

The specific capacitance of materials influences the energy storage capacity. A series of MgxNi1-xCo2O4 (x = 0.0 - 0.1) nanoparticles using the low-temperature microwave-hydrothermal (M-H) method at 160 0C temperature, and sintered at 600 °C. The samples were then characterized using X-ray diffraction (XRD), Field Emission Scanning electron microscopy (FE-SEM), Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS). It is observed from X-ray diffraction that all the samples are cubic spinel in nature with space group Fd-3m, and the lattice parameter varies between 8.097 (x = 0.0) and 8.083 (x = 0.10). The nanoparticles have a hexagonal nanoflake-like shape morphology with an average particle size of 180 nm to 350 nm. The tetrahedral and octahedral absorption bands were observed at 561 cm-1 and 654 cm-1, respectively. The valence states of Ni2+/Ni3+, Co2+/Co3+, and Mg2+ were confirmed by X-ray photoelectron spectroscopy. The electrochemical studies using CV and GCD were performed on all the samples. High values of specific capacitance of 332 F g−1, energy densityof 9.05 Wh kg-1, and power density of 224.84 W kg-1 were observed for the sample x = 0.08. Therefore, Mg0.08Ni0.92Co2O4 sintered at 600 °C shows good impedance and electrochemical properties, which are helpful for supercapacitor applications.

Figure 1
Prediction of Lithium Deposition By Electrochemical Noise Method in Li-Ion Batteries
Authors: Karaoglu Gozde , Ülgüt Burak
Published: August 2024

Electrochemical noise measurement methods have established a significant presence in corrosion literatures and through these measurements, it becomes feasible to discern the corrosion mode and make a clear distinction between localized and uniform corrosion types, particularly when examined alongside post-mortem studies.

In recent years, the increase in the use of lithium-ion batteries demands that the tests to be performed on the batteries are faster, easier, cheaper and, if possible, non-destructive and non-perturbing. While some electrochemical noise studies on batteries have commenced, the existing literature on this subject is limited and questionable. Electrochemical noise measurement, in Lithium based batteries has the potential to serve as a non-invasive diagnostic tool for assessing battery health. One of our previous studies has demonstrated an increased voltage noise in non-rechargeable batteries with Li/MnO2 chemistry upon exposure to a short circuit, indicating detectable morphological changes in metallic lithium due to non-homogenous depletion of lithium anode through electrochemical noise measurement.

In Lithium-Ion batteries, lithium deposition refers to the undesired formation of metallic lithium, commonly in the form of dendrites, on the battery’s anode during charge and discharge cycles. This phenomenon is a consequence of uneven lithium-ion plating and stripping, leading to localized overplating. This growth of lithium dendrites poses significant risk, including internal short circuits, compromised battery integrity, and the potential for thermal runaway. These issues can result in reduced battery performance, safety concerns, and shortened cycle life. Effectively addressing lithium deposition is essential for enhancing the safety and reliability of lithium-ion batteries in various applications.

Similarly to our previous publication, the electrochemical noise method shows promise as a non-invasive approach to investigate the understand deposition of metallic lithium by monitoring the voltage noise during charge and discharge cycling of batteries. For this purpose, NMC/Graphite pouch and coin cells are employed. In this presentation, we will delve into the details of electrochemical noise in lithium-based batteries, discussing the method’s reliability in assessing lithium deposition in NMC/Graphite lithium-ion batteries and presenting preliminary results.

Figure 1
Evaluating the Performance of an All-Aqueous Copper Trab through 200 Hours of Discharge Cycling
Authors: Rochin Jose A. , Cross Nicholas R. , Bachman Ridge M. , Hall Derek M.
Published: August 2024

Thermally regenerative ammonia batteries (TRABs) have the potential to serve as a viable solution for energy storage and electricity generation by harnessing low-grade heat. A TRAB discharge closely resembles that of a conventional flow battery, where electrochemical reactions are used to produce electrical power and aqueous electrolytes are stored in external tanks. However, the key distinction of a TRAB from a conventional flow battery lies in the recharging process, where thermal energy is used to separate ammonia from the negolyte, referred to as thermal recharging. During thermal recharging, the exhausted negolyte is converted into a fresh posolyte through the thermal separation of ammonia that was dissolved into the solution. This separated ammonia is subsequently added into the depleted posolyte, turning it into a fresh negolyte thereby completing the recharging process. Although there are many types of TRABs, the all-aqueous copper TRAB (Cuaq-TRAB) has produced some of the largest power densities and energy storage densities observed from a TRAB discharge. Building on these recent successes with Cuaq-TRABs, our investigation seeks to assess the performance of the Cuaq-TRAB during prolonged operation. Previous investigations with TRABs have typically lasted 0.5-7 hours, with the longest lasting 20 hours, which does not provide sufficient data to demonstrate the stability of the technology as thousands of hours of operation will be required. To address this gap, we operated an Cuaq-TRAB for 200 hours with a constant discharge current density of 10 mA cm-2 to examine battery performance and material degradation over time. Throughout the 200-hour test period, we measured an average power density of 7.2 mW cm⁻², which increased by 0.01% during the test. Additionally, the average energy density was 2.7 Wh L⁻¹, with a degradation of only 0.03% over the 200-hour timeframe. These results are the first to provide valuable information about the stability of the Cuaq-TRAB system during extended operation.
(Invited) Is the [5,5] C120-D5d Fullertube a Metal?
Authors: Dorn Harry , Stevenson Steven
Published: August 2024

Single-walled nanotubes (SWNTs) with a roll-up vector (n = m) have long been predicted to exhibit metallic behavior at infinite nanotube lengths.1 Moreover, in contrast with normal metals, armchair nanotubes e.g., [5,5] should result in exceptional ballistic transport properties.2 However, the question remains at what finite length of a SWNT or fullertube does metallic character begin, if at all. From a computational viewpoint, Cioslowski has shown that the HOMO-LUMO bandgap decreases to ~1 eV in an oscillatory fashion in approaching [5,5] C200 fullertubes.3 Although the HOMO-LUMO gap has been extensively used to predict the kinetic stability of fullerenes and metallofullerenes with less than 100 carbon atoms, Fowler has argued that the HOMO-LUMO gap can not be used to predict the kinetic stability of large fullerenes.4 More recently, Lilijeroth and coworkers have measured the experimental and DFT HOMO-LUMO gap for graphene nanoribbons (GNR) and find that GNRs with lengths of 5 nm have bandgaps of ~0.1 eV.5 These workers also point out that DFT calculated HOMO-LUMO bandgaps are always overestimated relative to experimental values. In this presentation, I will present the evidence in support of metallic character for [5,5] C120-D5d.6,7

References:

1. Mintmire, J. W.; Dunlap, B. I.; White, C. T. Are Fullerene Tubules Metallic? Phys. Rev. Lett. 1992, 68, 631−634.

2. White, C. T.; Todorov, T. N. Carbon Nanotubes as Ballistic Conductors. Nature 1998, 393, 240−242.

3. Cioslowski, J.; Rao, N.; Moncrieff, D. Electronic Structures and Energetics of [5,5] and [9,0] Single-Walled Carbon Nanotubes. J. Am. Chem. Soc. 2002, 124 (28), 8485−8489.

4. Fowler, P., Nature (London), 1991, 350, 20.

5. Kimouche, A., Ervasti, M. M., Drost, R., Halonen, S., Harju, A,. Joensuu, M. P., Sainio, J., Liljeroth P., Ultra-narrow metallic armchair graphene nanoribbons. Nature Communications, 2015, 6 (1) 1-5.

6. Stevenson, S.; Liu, X.; Sublett, D. M., Jr; Koenig, R. M.; Seeler, T. L.; Tepper, K. R.; Franklin, H. M.; Wang, X.; Huang, R.; Feng, X.; et al. Semiconducting and Metallic [5,5] Fullertube Nanowires: Characterization of Pristine D5h(1)-C90 and D5d(1)-C100. J. Am. Chem. Soc. 2021, 143 (12), 4593−4599.

7. Liu, X.; Bourret, E.; Noble, C. A.; Cover, K.; Koenig, R. M.; Huang, R.; Franklin, H. M.; Feng, X.; Bodnar, R. J.; Zhang, F.; et al. Gigantic C120 Fullertubes: Prediction and Experimental Evidence for Isomerically Purified Metallic [5,5] C120-D5d(1) and Nonmetallic [10,0] C120-D5h(10766). J. Am. Chem. Soc. 2022, 144 (36), 16287−16291.
(Invited) Metallofullertubes or Metallofullerenes: Which Have We Isolated?
Authors: Davidson Tanisha , Noble Cora A. , Bourret Emmanuel , Stevenson Steven
Published: August 2024

In our labs, we are isolating several novel carbon-metal endohedral molecules of unknown structures with rare-earth metals. In this presentation, we will discuss the feasibility of using chemical reactivity differences (Round 1) to obtain samples enriched in their presence. Next, using a multiple column HPLC approach for further resolution (Round 2), we have isolated and begun a preliminary characterization (e.g., UV-vis) for these pristine samples. We know their chemical formulas, but we do not yet know the structural arrangement of metal and carbon atoms. When sufficient quantities are obtained, we will pursue X-ray crystallography to address the following big question. Namely, do we have metals in tubes (metallofullertubes) or do we have metals in big balls (metallofullerenes). An objective of this presentation is to update and share with the fellow scientific community our most recent advances and progress in the research area of larger carbon cage structural housings (e.g., C96-C120).
(Invited) Synthesis and Functionalization of Nanographenes with Red to Near-Infrared Emission for Photonic Applications
Authors: Narita Akimitsu
Published: August 2024

Nanostructures of graphene demonstrate a wide range of optical, electronic, and magnetic properties depending on their size and chemical structures, which renders them promising as next-generation carbon-based nanomaterials, e.g., for nanoelectronics, spintronics, and photonics. However, it is challenging to accurately control the chemical structures while “cutting” graphene. To this end, large polycyclic aromatic hydrocarbons (PAHs) with nanoscale graphene structures are attracting a renewed attention as atomically precise nanographenes [1]. We have developed the synthesis of dibenzo[hi,st]ovalene (DBOV) as an unprecedented nanographene with high stability, strong red fluorescence, and stimulated emission, demonstrating the potential for organic lasers [2]. The functionalization of DBOV was achieved through regioselective bromination and Suzuki coupling, enabling the introduction of various substituents, for example fluoranthene imide (FAI) groups, inducing the red-shift of the emission to the near-infrared (NIR) region [3]. Different effects on the photophysical properties of the DBOV core have been observed by changing the peripheral functional groups. More recently, we have synthesized hexabenzoperihexacene (HBPH) with zigzag and fjord edges, which displayed high stability and NIR emission with maximum at ~800 nm [4]. Notably, HBPH could be made chiral by introducing bulky tert-butyl groups on the helical fjord edges, allowing the separation of the enantiomers and showing the circular dichroism responses up to 830 nm. These results provide a new insight into the structure-property relationship of such nanographenes and pave the way toward their photonic applications.

[1] Paternò, G. M.; Goudappagouda,; Chen, Q.; Lanzani, G.; Scotognella, F; Narita A., Adv. Optical Mater. 2021, 9, 2100508.

[2] Paternò, G. M.; Chen, Q.; Wang, X.-Y.; Liu, J.; Motti, S. G.; Petrozza, A.; Feng, X.; Lanzani, G.; Müllen, K.; Narita, A.; Scotognella, F., Angew. Chem. Int. Ed.
2017,
56, 6753–6757.

[3] Paternò, G. M.; Chen, Q.; Muñoz-Mármol, R.; Guizzardi, M.; Bonal, V.; Kabe, R.; Barker, A. J.; Boj, P. G.; Chatterjee, S.; Ie, Y.; Villalvilla, J. M.; Quintana, J. A.; Scotognella, F.; Müllen, K.; Díaz-García, M. A.; Narita, A.; Lanzani, G., Mater.
Horiz. 2022, 9, 393–402.

[4] Xu, X.; Muñoz-Mármol, R.; Vasylevskyi, S.; Villa, A.; Folpini, G.; Scotognella, F.; Paternò, G. M.; Narita, A., Angew. Chem. Int. Ed.
2023, 62, e202218350.
(Invited) Thermally Selective Skeletal Rearrangements at Interfaces
Authors: Ecija David
Published: August 2024

Thermal rearrangements, in which an atom, ion or chemical unit of a molecule is rearranged to obtain a structural isomer of the original molecule under a thermal stimulus, represents an excellent alternative to induce the formation of novel antiaromatic PCHs and conjugated polymers not accessible otherwise. Only recently, a few strain-induced rearrangement reactions of precursors that are composed of rigid and strained three dimensional (3D) structures have shown skeletal rearrangements in their backbone after planarization on metal surfaces. In this respect, the selectivity of on-surface chemical reaction pathways is a promising approach to increase synthetic versatility, though remains largely underexplored. In this talk I will review our recent discoveries regarding the exploitation of thermal rearrangements to form 0D, 1D and 2D unique molecular nanocarbons.
(Invited) Electrochemistry of the 1,1,N,N-Tetramethyl[N](2,11)Teropyrenophanes
Authors: Hahn Nolan , Unikela Kiran Sagar , Boeré René , Bodwell Graham
Published: August 2024

Polycyclic aromatic hydrocarbons (PAH) have been of broad interest for many decades. This is due largely to their extended π systems, which imbue them with optical and electronic properties that can be exploited in a variety of organic electronic devices. A current trend in PAH chemistry is the construction of ever-larger and more elaborate aromatic systems. A major challenge associated with this work is to maintain solubility. For innately planar PAH, the standard tactic is to append multiple solubilizing groups to the periphery of the aromatic system. The drawbacks to this are that 1) the mass of solubilizing groups can outweigh that of the PAH, 2) the presence of the solubilizing groups severely limits or rules out doing chemistry on the periphery and 3) the tactic becomes less and less effective as the size of the PAH becomes very large. An alternative and very effective way to boost solubility is to bring about nonplanarity in a PAH. This can be achieved through the presence of nonbonded interactions (as in helicenes), the presence of non-6-membered rings (as in corannulene) and by bridging the aromatic system (i.e. incorporating it into a cyclophane).

Cyclophanes constitute a very large and diverse class of compounds. The simplest cyclophanes (the [n]cyclophanes) consist of just one aromatic system and one aliphatic bridge. These cyclophanes are especially interesting because the structure of the aromatic system can be changed by varying the length of the bridge. This enables the study of how the chemical and physical properties of a particular PAH are affected by incremental changes in structure without any complications arising from intramolecular π-π interactions or changes in the character or position of the substituents (the bridge). Understanding the relationships between structure and properties can underpin efforts to tailor properties of organic compounds for use as materials in devices. Very few [n]cyclophanes that have a large PAH are known, so there is plenty of room for exploration in this area.

The PAH of interest in this work is teropyrene. It is a member of the ropyrene series of aromatic compounds, which evolve into armchair-edged graphene nanoribbons (GNR) as they propagate. Teropyrene has 10 6-membered rings, 36 carbon atoms and vanishingly low solubility. Only a handful of teropyrene derivatives are known. We have developed a synthetic route to a series of 1,1,n,n-tetramethyl[n](2,11)teropyrenophanes (n = 7-10), which feature a teropyrene system with an end-to-end bend ranging from 145° (n = 10) to 178° (n = 7) and have very good solubility in a variety of organic solvents. Details of the redox behaviour of these teropyrenophanes will be presented.

Figure 1
(Invited) Distance Dependent Electron Transfer Kinetics in Water Soluble Axially Connected Silicon Phthalocyanine-Fullerene Conjugates
Authors: Sastre-Santos Angela
Published: August 2024

The effect of donor-acceptor distance in controlling the rate of electron transfer in axially linked silicon phthalocyanine – C60 dyads has been investigated. Herein we will presented the synthesis and photophysical properties of two water soluble C60-SiPc-C60 dyads, 1 and 2, varying in their donor-acceptor distance.In previous investigation for C60-SiPc-C60 dyads where the SiPc and C60 are separated by a phenyl spacer, faster electron transfer was observed with k
cs equal to 2.7 x 109 s-1 in benzonitrile. However, in the case of C60-SiPc-C60, where SiPc and C60 are separated by a biphenyl spacer, a slower electron transfer rate constant, k
cs equal to 9.1 x108 s-1 was recorded. The addition of an extra phenyl spacer in 2 increased the donor-acceptor distance by ~ 4.3 Å, and consequently, slowed down the electron transfer rate constant by a factor of ~3.7. The charge separated state lasted over 3 ns, monitoring time window of our femtosecond transient spectrometer. Complimentary nanosecond transient absorption studies revealed formation of 3SiPc* as the end product and suggested that the final lifetime of charge separated state to be in the 3-20 ns range. Energy level diagram established to comprehend these mechanistic details indicated that the comparatively high-energy SiPc
.+
-C60

.-
charge separated states (1.57 eV) to populate the low-lying 3SiPc* (1.26 eV) prior returning to the ground state.[1]

Here we will present our recent results using water soluble SiPc-C60
1-2 systems where the SiPc is substituted with pyridine units.[3]

Acknowledgments

This work was supported by the Ministerio de Ciencia e Innovación of Spain and FEDER funds (Grants PID2020-117855RB-I00 to ASS) and National Science Foundation (Grant No. 1401188 and 2000988 to FD).

References

L. Martín-Gomis, S. Seetharaman, D. Herrero, P. A. Karr, F. Fernández-Lázaro, F. D’Souza, and Á. Sastre-Santos, Chem Phys. Chem.,
2020, 21, 2254-2262.

V. Sobrino, L. Martín-Gomis, S. Seetharaman, P. A. Karr, D’Souza, and Á. Sastre-Santos, under preparation.

Figure 1