bluuebunny/crossref_metadata_2025 huggingface dataset:
Bioinspired Hierarchical Structures for Contact‐Sensible Adhesives
Authors: Hu Hong , Wang Duorui , Tian Hongmiao , Huang Qiyao , Wang Chunhui , Chen Xiaoliang , Gao Yuan , Li Xiangming , Chen Xiaoming , Zheng Zijian , Shao Jinyou
Published: November 2021

Bioinspired structural adhesives that are capable of bonding two objects together have recently found widespread applications in industrial fields, because of their promising reusability and environmental friendliness. However, such adhesives are usually monofunctional and cannot yield real‐time detection on the adhesion status, which is important for both biological systems (e.g., Gecko) and engineered mimics. This study reports a new hierarchical structure with the monolithic integration of adhesion and sensing functions, namely, contact‐sensible adhesive (CSA). The proposed CSA is composed of mushroom‐shaped microstructures on the top layer for providing strong adhesion, and a pillar array sandwiched by a pair of foil electrodes on the bottom layer as a compliant backing and a capacitive sensor. The CSA is not only sensitive to the external pressure, tension, and shear loads, but also shows enhanced adhesion on uneven surfaces, due to the high compliance of the hierarchical system. As a proof of concept, the as‐prepared CSA is applied as a contact interface in a gripper to complete the grasping task.
Microswimmers from Toposelective Nanoparticle Attachment
Authors: Bailey Maximilian R. , Grillo Fabio , Spencer Nicholas D. , Isa Lucio
Published: November 2021

Microswimmers hold promise for applications ranging from targeted delivery to enhanced mixing at the microscale. However, current fabrication techniques suffer from limited throughput and material selection. Here, a versatile route enabling the synthesis of microswimmers from off‐the‐shelf micro‐ and nano‐particles is demonstrated. The protocol hinges on the toposelective attachment of photocatalytic nanoparticles onto microparticles, exploiting a multi‐functional polymer and a Pickering‐wax emulsification step, to yield large quantities of photo‐responsive active Janus particles. The polymer presents both silane and nitrocatechol groups, binding silica microspheres to a range of metal oxide nanoparticles. The Pickering‐wax emulsions protect part of the microspheres’ surface, enabling asymmetric functionalization, as required for self‐propulsion. The resulting photocatalytic microswimmers display a characteristic orientation‐dependent 3D active motion upon ultra‐violet illumination, different from that conventionally described in the literature. By connecting the extensive library of heterogeneous nanoparticle photocatalysts with the nascent field of active matter, this versatile material platform lays the groundwork toward designer microswimmers, which can swim by catalyzing a broad range of chemical reactions with potential for future applications.
Quasi‐2D Perovskite Thick Film for X‐Ray Detection with Low Detection Limit
Authors: He Xin , Xia Mengling , Wu Haodi , Du Xinyuan , Song Zihao , Zhao Shan , Chen Xu , Niu Guangda , Tang Jiang
Published: November 2021

Organic‐inorganic hybrid perovskites have demonstrated excellent performance in converting X‐ray photons to electrical signals with high detectivity and sensitivity. Solution‐processed large‐area perovskite polycrystalline thick film is promising for scalable X‐ray flat panel detection imaging. However, ionic migration is severe due to the numerous grain boundaries and pinholes in the thick films, resulting in a large dark current and serious baseline drift. Herein, a new strategy is proposed to suppress the ion migration by inserting 2D Ruddlesden–Popper layer into the 3D perovskite film. The quasi‐2D perovskite thick films exhibit lower defects density, suppressed ion migration, and higher thermal stability compared to their 3D counterpart. Based on these advantages, the quasi‐2D perovskite‐based X‐ray detector shows a sensitivity of 10 860 µC Gyair−1 cm−2 with a stable dark current and photocurrent response. Impressively, the extra‐low detection limit of 69 nGyair s−1 is the lowest in all those reported polycrystalline film‐based detectors. The quasi‐2D film is believed to be a very promising choice for digital flat detectors for sensitive radiation detection and low‐dose dosimeter.
A Biomimetic Nonantibiotic Nanoplatform for Low‐Temperature Photothermal Treatment of Urinary Tract Infections Caused by Uropathogenic Escherichia coli
Authors: Wenjie Shi , Jinxia An , He Tan , Mengran Jia , Hui Gao
Published: November 2021

Urinary tract infections (UTIs) caused by uropathogenic Escherichia coli (UPEC) remain a matter of concern, as the clinical use of multiple antibiotics induces antibiotic resistance in bacteria, resulting in the failure of treatments. Despite the emergence of anti‐adhesion strategies that can prevent the development of bacterial drug resistance, these strategies are mainly used for disease prevention rather than effective treatment. Photothermal therapy (PTT) has emerged as an efficient alternative for the elimination of bacteria. Nevertheless, high local temperatures related to PTT probably cause damage to surrounding healthy tissue. Herein, a biomimetic nonantibiotic nanoplatform for low‐temperature photothermal treatment of UTIs is developed. The nanoplatform comprises polydopamine (PDA) photothermal core and biphenyl mannoside (Man) shell with multivalent high‐affinity to UPEC. Scanning electron microscope (SEM) shows PDA‐Man possessed ultra‐strong targeting binding ability toward UPEC. It is the fact that this impulse UPEC to form a large bacterial cluster. Consequently, the high photothermal energy of the PDA‐Man appears predominantly in the affected bacterial area, while the overall environment remains at a low temperature. The fabricated nanoplatform shows excellent photothermal bactericidal effects, approximately 100% in a UTI model. Overall, this low‐temperature photothermal nanoplatform provides an appropriate strategy for the elimination of bacteria in clinical applications.
Nucleic Acid Delivery from Granular Hydrogels
Authors: Kurt Evan , Segura Tatiana
Published: November 2021

Nucleic acid delivery has applications ranging from tissue engineering to vaccine development to infectious disease. Cationic polymer condensed nucleic acids are used with surface‐coated porous scaffolds and are able to promote long‐term gene expression. However, due to surface loading of the scaffold, there is a limit to the amount of nucleic acid that can be loaded, resulting in decreasing expression rate over time. In addition, surface‐coated scaffolds are generally non‐injectable. Here, it is demonstrated that cationic polymer condensed nucleic acids can be effectively loaded into injectable granular hydrogel scaffolds by stabilizing the condensed nucleic acid into a lyophilized powder, loading the powder into a bulk hydrogel, and then fragmenting the loaded hydrogel. The resulting hydrogel microparticles contain non‐aggregated nucleic acid particles, can be annealed post‐injection to result in an injectable microporous hydrogel, and can effectively deliver nucleic acids to embedded cells with a constant expression rate. Due to the nature of granular hydrogels, it is demonstrated that mixtures of loaded and unloaded particles and spatially resolved gene expression can be easily achieved. The ability to express genes long term from an injectable porous hydrogel will further open the applications of nucleic acid delivery.
Shape‐Changing Particles: From Materials Design and Mechanisms to Implementation
Authors: Tanjeem Nabila , Minnis Montana B. , Hayward Ryan C. , Shields Charles Wyatt
Published: November 2021

Demands for next‐generation soft and responsive materials have sparked recent interest in the development of shape‐changing particles and particle assemblies. Over the last two decades, a variety of mechanisms that drive shape change have been explored and integrated into particulate systems. Through a combination of top‐down fabrication and bottom‐up synthesis techniques, shape‐morphing capabilities extend from the microscale to the nanoscale. Consequently, shape‐morphing particles are rapidly emerging in a variety of contexts, including photonics, microfluidics, microrobotics, and biomedicine. Herein, the key mechanisms and materials that facilitate shape changes of microscale and nanoscale particles are discussed. Recent progress in the applications made possible by these particles is summarized, and perspectives on their promise and key open challenges in the field are discussed.
Biomimetic Trachea Engineering via a Modular Ring Strategy Based on Bone‐Marrow Stem Cells and Atelocollagen for Use in Extensive Tracheal Reconstruction
Authors: Xu Yong , Dai Jie , Zhu Xinsheng , Cao Runfeng , Song Nan , Liu Ming , Liu Xiaogang , Zhu Junjie , Pan Feng , Qin Linlin , Jiang Gening , Wang Haifeng , Yang Yang
Published: November 2021

The fabrication of biomimetic tracheas with a architecture of cartilaginous rings alternately interspersed between vascularized fibrous tissue (CRVFT) has the potential to perfectly recapitulate the normal tracheal structure and function. Herein, the development of a customized chondroitin‐sulfate‐incorporating type‐II atelocollagen (COL II/CS) scaffold with excellent chondrogenic capacity and a type‐I atelocollagen (COL I) scaffold to facilitate the formation of vascularized fibrous tissue is described. An efficient modular ring strategy is then adopted to develop a CRVFT‐based biomimetic trachea. The in vitro engineering of cartilaginous rings is achieved via the recellularization of ring‐shaped COL II/CS scaffolds using bone marrow stem cells as a mimetic for native cartilaginous ring tissue. A CRVFT‐based trachea with biomimetic mechanical properties, composed of bionic biochemical components, is additionally successfully generated in vivo via the alternating stacking of cartilaginous rings and ring‐shaped COL I scaffolds on a silicone pipe. The resultant biomimetic trachea with pedicled muscular flaps is used for extensive tracheal reconstruction and exhibits satisfactory therapeutic outcomes with structural and functional properties similar to those of native trachea. This is the first study to utilize stem cells for long‐segmental tracheal cartilaginous regeneration and this represents a promising method for extensive tracheal reconstruction.
Highly Efficient Self‐Healing Multifunctional Dressing with Antibacterial Activity for Sutureless Wound Closure and Infected Wound Monitoring
Authors: Tang Ning , Zhang Rongjun , Zheng Youbin , Wang Jing , Khatib Muhammad , Jiang Xue , Zhou Cheng , Omar Rawan , Saliba Walaa , Wu Weiwei , Yuan Miaomiao , Cui Daxiang , Haick Hossam
Published: November 2021

Wound healing represents a major clinical and public healthcare problem that is frequently challenged by infection risks, detrimental consequences on the surrounding tissues, and difficulties to monitor the healing process. Here we report on a novel self‐healing, antibacterial, and multifunctional wound dressing for sutureless wound closure and real‐time monitoring of the healing parameters. The self‐healing elastomer contains cetyltrimethylammonium bromide (CTAB) and has high mechanical toughness (35 MJ m−3), biocompatibility, and outstanding antibacterial activity (bactericidal rate is ≈90% in 12 h), enabling the wound dressing to effectively inhibit bacterial growth and accelerate infected wound healing. In vivo tests based on full‐thickness skin incision model shows that the multifunctional wound dressing can help in contracting wound edges and facilitate wound closure and healing, as could be evidenced by notably dense and well‐organized collagen deposition. The test provides an evidence that the integrated sensor array within the multifunctional wound dressing can monitor temperature, pH, and glucose level of the wound area in real‐time, providing reliable and timely information of the condition of the wound. Ultimately, the reported multifunctional dressing would be of high value in managing the burden associated with wound healing via personalised monitoring and treatment approaches, digital and other people‐centred solutions for health care.
The Road for 2D Semiconductors in the Silicon Age
Authors: Wang Shuiyuan , Liu Xiaoxian , Zhou Peng
Published: November 2021

Continued reduction in transistor size can improve the performance of silicon integrated circuits (ICs). However, as Moore's law approaches physical limits, high‐performance growth in silicon ICs becomes unsustainable, due to challenges of scaling, energy efficiency, and memory limitations. The ultrathin layers, diverse band structures, unique electronic properties, and silicon‐compatible processes of 2D materials create the potential to consistently drive advanced performance in ICs. Here, the potential of fusing 2D materials with silicon ICs to minimize the challenges in silicon ICs, and to create technologies beyond the von Neumann architecture, is presented, and the killer applications for 2D materials in logic and memory devices to ease scaling, energy efficiency bottlenecks, and memory dilemmas encountered in silicon ICs are discussed. The fusion of 2D materials allows the creation of all‐in‐one perception, memory, and computation technologies beyond the von Neumann architecture to enhance system efficiency and remove computing power bottlenecks. Progress on the 2D ICs demonstration is summarized, as well as the technical hurdles it faces in terms of wafer‐scale heterostructure growth, transfer, and compatible integration with silicon ICs. Finally, the promising pathways and obstacles to the technological advances in ICs due to the integration of 2D materials with silicon are presented.
Manipulating Electroluminochromism Behavior of Viologen‐Substituted Iridium(III) Complexes through Ligand Engineering for Information Display and Encryption
Authors: Wang Xuecheng , Kuang Jianru , Wu Pengcheng , Zong Zheng , Li Zixian , Wang Hao , Li Jinlu , Dai Peiling , Zhang Kenneth Yin , Liu Shujuan , Huang Wei , Zhao Qiang
Published: November 2021

Electrically controlling photoluminescence has attracted great research interest and offers many opportunities for technological developments. Electroluminochromic materials undergo redox reactions under low‐voltage stimuli to achieve reversible luminescence switching. Till now, photoluminescence switching of a single molecule caused by electrical stimuli is restricted to intensity response because the redox‐active moieties are good electron donors or acceptors and electrical stimuli can regulate the photoinduced electron‐transfer and affect the luminescence intensity. In this work, the manipulation of the electroluminochromism behavior of a series of viologen‐substituted iridium(III) complexes through the regulation of ligand orbital energy levels and electronic communication between the viologen pendants and the iridium(III) complex core is reported. Electrochemical redox reactions reversibly modulate either the luminescence quenching effect or the push–pull electronic effect of the viologen substituents, achieving multicolor “on–off” luminescence response toward electrical stimuli and luminescence manipulation between two emissive states with different wavelengths and lifetimes. To illustrate the promising applications of these electroluminochromic materials, recording and displaying luminescence information under electrical stimuli are demonstrated. Information encryption is realized by letting the electroluminochromism occur in the near‐infrared region or in the time domain. Near‐infrared camera or time‐resolved luminescence analysis can be used to help read the invisible information.
Nanostructure Control in 3D Printed Materials
Authors: Bobrin Valentin A. , Lee Kenny , Zhang Jin , Corrigan Nathaniel , Boyer Cyrille
Published: November 2021

Currently, there are no straightforward methods to 3D print materials with nanoscale control over morphological and functional properties. Here, a novel approach for the fabrication of materials with controlled nanoscale morphologies using a rapid and commercially available Digital Light Processing 3D printing technique is demonstrated. This process exploits reversible deactivation radical polymerization to control the in‐situ‐polymerization‐induced microphase separation of 3D printing resins, which provides materials with complex architectures controllable from the macro‐ to nanoscale, resulting in the preparation of materials with enhanced mechanical properties. This method does not require specialized equipment or process conditions and thus represents an important development in the production of advanced materials via additive manufacturing.
Recent Advances on MXene‐Based Electrocatalysts toward Oxygen Reduction Reaction: A Focused Review
Authors: Peera Shaik Gouse , Liu Chao , Sahu Akhila Kumar , Selvaraj Manickam , Rao M. C. , Lee Tae Gwan , Koutavarapu Ravindranadh , Shim Jaesool , Singh Lakhveer
Published: November 2021

MXenes are novel transition‐metal‐carbide‐ and/or nitride‐based 2D materials that attract considerable attention in the field of energy storage and conversion because of their unique layered structures, electronic properties, and surface chemistries, which facilitate various electrochemical reactions. MXenes have been rarely investigated as probable catalysts or catalyst supports for the oxygen reduction reaction (ORR). In this review, recent developments in experimental and theoretical research on MXene‐based electrocatalysts for the ORR are examined. MXenes are known to have tremendous potential as stable supports for various Pt and non‐Pt metals for electrocatalytic ORR processes. Theoretical analyses have determined several potential MXene candidates for applications as supports for Pt and non‐Pt metal nanoparticles; experimental studies have shown that Pt‐ and non‐Pt‐deposited MXenes exhibit appreciable ORR activity and stability in alkaline media, followed by acidic media. However, experimental studies also indicate several limitations and challenges that must be addressed for efficient application of MXenes as supports for the ORR. Therefore, current research on MXenes with respect to the ORR is discussed, with a focus on synthesis strategies, ORR activities, and factors responsible for enhancing the electrocatalytic performance. Several strategies for the further development of efficient and durable ORR‐based MXene catalysts are also proposed.
Spin‐Charge Conversion in Fe/Au/Sb2Te3 Heterostructures as Probed By Spin Pumping Ferromagnetic Resonance
Authors: Longo Emanuele , Locatelli Lorenzo , Belli Matteo , Alia Mario , Kumar Arun , Longo Massimo , Fanciulli Marco , Mantovan Roberto
Published: November 2021

Large‐area antimony telluride (Sb2Te3) thin films are grown by a metal organic chemical vapor deposition technique on 4” Si(111) substrates, and their topological character probed by magnetoconductance measurements. When interfaced with Fe thin films, broadband ferromagnetic resonance spectroscopy (BFMR) shows a clear increase of the damping parameter in Fe/Sb2Te3 when compared to a reference Fe layer, which may suggest the occurrence of spin pumping (SP) into Sb2Te3. Simultaneously, X‐ray reflectivity and conversion electron Mossbauer spectroscopy evidence the development of a chemically and magnetically pure Fe/Sb2Te3 interface. However, by conducting SP‐FMR, it is shown that no spin‐to‐charge conversion (S2C) occurs in Fe/Sb2Te3, while a clear SP signal develops by introducing a 5 nm Au interlayer between Fe and Sb2Te3, with a measured inverse Edelstein effect conversion efficiency of λIEE = 0.27 nm. The results shed some light on the correlation among the chemical‐structural‐magnetic properties of the Fe/Sb2Te3 interface, the broadening of the magnetic damping parameter as detected by BFMR, and the occurrence of S2C, as probed by SP‐FMR.
Solution‐Processed Graphene Thin‐Film Enables Binder‐Free, Efficient Loading of Nanocatalysts for Electrochemical Water Splitting
Authors: Cho Yun Seong , Rhee Dongjoon , Kim Hee Jun , Kim Hyun Seung , Baik Jeong Min , Kang Joohoon
Published: November 2021

Electrochemical water splitting is promising to produce high purity hydrogen that can serve as clean and renewable energy. Reducing the size of catalysts down to the nanometer regime is critical for enhancing the electrochemical performance because reactions mostly occur at the surface of materials. However, fully exploiting the advantage of small nanocatalysts is challenging because accessible catalytic surface area is reduced by particle aggregation and the use of binders. In addition, a significant fraction of nanocatalysts is lost through the electrode pores during catalyst loading. Here, a simple strategy to efficiently load nanocatalysts without using binders is reported. By introducing a thin layer of graphene nanosheets on a porous membrane, a uniform nanocatalyst film via vacuum filtration of the dispersion can be created. The nanocatalyst/graphene composite can be transferred to a carbon paper without fracturing to function as a catalyst layer. The method is compatible with various nanomaterials to realize electrodes for hydrogen and oxygen evolution reactions and even bifunctional electrodes that exhibit activities for both. Significantly, the resulting electrodes show better performance than those produced by directly filtrating through the carbon paper. Moreover, the binder‐free surface allows for further enhancement in catalytic activity via postchemical treatments.
Hierarchically Structured Components: Design, Additive Manufacture, and Their Energy Applications
Authors: Wang Panfeng , Xuan Jin , Zhang Ronghao , Zhang Hao , Wang Qiang , Wang Haoyang , Liu Houli , Zhang Li
Published: November 2021

Pursuing high energy efficiency and reaction rate is an effective direction in mitigating the energy and climate crisis. Mass transfer intensification is a powerful approach to enhance the energy efficiency and reaction rate in the energy conversion and storage processes. The nature‐inspired channels are outstanding tools to uniformly distribute the reactants, fast remove products, and reduce the diffusion distance for mass transfer intensification in monolithic adsorbents, structured catalysts, and electrodes. Besides, hierarchical pores are also a contributor to improve the reactant diffusion rate in the matrix. Additive manufacturing, combining the design of printing material and post‐treatment, provides a promising opportunity to accurately control the channels and adjust the pores in electrodes, catalysts, and adsorbents. This review summarizes the main state‐of‐the‐art methods to design ideal channels and to control the sizes and amounts of pores for the optimum hierarchical structure design, as well as the techniques to realize the hierarchical structure by additive manufacturing. In addition, this review also communicates the recently unlocked advantages of the designable channels and hierarchical pores in applications of adsorptions, chemical reactions, and electrochemical energy storage. Lastly, a new approach to design and fabricate the hierarchical structures is proposed, along with its potential benefits.
Mode‐Center Placement of Monolayer WS2 in a Photonic Polymer Waveguide
Authors: Frank Angelina , Zhou Justin , Grieve James A. , Verzhbitskiy Ivan , Viana‐Gomes José , Loh Leyi , Schmid Michael , Watanabe Kenji , Taniguchi Takashi , Eda Goki , Ling Alexander
Published: November 2021

The effective integration of 2D materials such as monolayer transition metal dichalcogenides (TMDs) into photonic waveguides and integrated circuits is being intensely pursued due to these materials’ strong exciton‐based optical response. This work presents a platform where a 2D heterostructure (WS2‐hBN) is directly integrated into the photonic mode‐center of a novel polymer ridge waveguide. Finite‐difference time‐domain simulations and collection of photoluminescence from the guided mode indicate that this system exhibits significantly improved waveguide‐emitter coupling and mode confinement over a previous elastomer platform. This is facilitated by the platform's enhanced refractive‐index contrast and a new method for mode‐center integration of the coupled TMD. The integration is based on a simple dry‐transfer process that is applicable to other 2D materials, and the platform's elastomeric nature is a natural fit to explore strain‐tunable hybrid‐photonic devices. The demonstrated ability of coupling photoluminescence to a polymer waveguide opens up new possibilities for hybrid‐photonic systems in a variety of contexts.
Single and Dual Doping of Blue‐Emissive ZnSeTe Quantum Dots with Transition Metal Ions
Authors: Song Seung‐Won , Lee Sun‐Hyoung , Jo Dae‐Yeon , Yoon Suk‐Young , Kim Hyun‐Min , Kim Yuri , Han Jee‐Na , Lee Young‐Ju , Do Young Rag , Yang Heesun
Published: November 2021

Doping particularly with transition metal ions is an effectual means to modulate photoluminescence (PL) of quantum dots (QDs). The precedent doped QDs rely primarily on single doping with either Cu+ or Mn2+ into the most common host compositions of (Zn)CdS, ZnSe, and InP, with little success on co‐doping with both impurities enabling their simultaneous emissions. Herein, single and dual doping are explored with Cu+ and/or Mn2+ into blue‐emissive ZnSeTe QDs. PL of the singly doped ZnSeTe QDs synthesized via a co‐nucleation process, comprising host and dopant emissions, is spectrally tuned by varying the concentration of each dopant. For the effective dual doping toward co‐emergence of both dopant‐related emissions, a two‐step doping strategy, where co‐nucleation doping of Mn2+ is temporally decoupled from diffusion doping of Cu+, is devised. In the resulting co‐doped ZnSeTe QDs, successfully showing three distinct emission components, the relative spectral distribution of triple emissions is readily modulated by individually adjusting Cu and Mn concentrations, producing color‐quality tunable white emissions. Upon elaborate multishelling, the co‐doped QDs display outstanding PL quantum yields of 72–75%. Singly and dually doped QDs are further applied for the fabrication of QD light‐emitting diodes, and their electroluminescence is examined compared to PL.
Spectral Emission Dependence of Tin‐Vacancy Centers in Diamond from Thermal Processing and Chemical Functionalization
Authors: Corte Emilio , Sachero Selene , Ditalia Tchernij Sviatoslav , Lühmann Tobias , Pezzagna Sébastien , Traina Paolo , Degiovanni Ivo Pietro , Moreva Ekaterina , Olivero Paolo , Meijer Jan , Genovese Marco , Forneris Jacopo
Published: November 2021

A systematic photoluminescence (PL) investigation of the spectral emission properties of individual optical defects fabricated in diamond upon ion implantation and annealing is reported. Three spectral lines at 620, 631, and 647 nm are identified and attributed to the SnV center due to their occurrence in the PL spectra of the very same single‐photon emitting defects. It is shown that the relative occurrence of the three spectral features can be modified by oxidizing the sample surface following thermal annealing. The relevant emission properties of each class of individual emitters, including the excited state emission lifetime and the emission intensity saturation parameters are reported.
Environment‐Dependent Metastable Nonradiative Recombination Centers in Perovskites Revealed by Photoluminescence Blinking
Authors: Chen Ruiyun , Xia Bo , Zhou Wenjin , Zhang Guofeng , Qin Chengbing , Hu Jianyong , Scheblykin Ivan G. , Xiao Liantuan
Published: November 2021

Organometal halide perovskites are promising materials for optoelectronic devices; however, nonradiative recombination under various atmospheric conditions severely affects the photostability of the materials and limits their potential applications. Further efforts to improve the stability are restricted by limited knowledge on nonradiative mechanisms. Herein, the contribution of nonradiative centers in photoluminescence (PL) response of methylammonium lead iodide (MAPbI3) crystals is resolved by studying atmosphere‐dependent PL blinking dynamics at single‐particle level. It is observed that interaction with nitrogen (N2) under illumination leads to PL quenching, revealing that N2 would activate highly efficient nonradiative recombination centers, which are previously passivated by oxygen (O2). In contrast, exposure to O2 results in the accumulation of the numbers of less‐efficient quenchers, leading to smooth PL decline. In a phenomenological model, the observed PL fluctuation is attributed to the switch of nonradiative recombination centers between their active and passive states and the change of the relative energy level. It is proposed that variation of stoichiometry from crystal to crystal causes the diverse PL response under different atmospheres. The results provide fundamental insights into the correlation between the nonradiative recombination sites and surrounding atmosphere conditions and may help for further improving the material quality and processing.
Energy Funneling in Quasi‐2D Ruddlesden–Popper Perovskites: Charge Transfer versus Resonant Energy Transfer
Authors: Gan Zhixing , Chen Weijian , Liu Cihui , Zhang Jinlei , Di Yunsong , Yu Liyan , Dong Lifeng , Jia Baohua , Wen Xiaoming
Published: November 2021

The quasi‐2D Ruddlesden–Popper perovskites contain a collection of grains with inhomogeneous bandgaps, enabling efficient energy funneling from high‐bandgap grains (donors) to low‐bandgap grains (acceptors), leading to localization of carriers and suppression of defect trapping. However, the exact mechanism for the energy funneling is still fiercely debated. Charge transfer (CT) via carrier diffusion and Förster resonance energy transfer (FRET) based on dipole interactions are the two conceivable models. Herein, by controlling the degree of energy funneling, both carrier dynamics of donors and acceptors are investigated. Transient absorption (TA) results suggest that the energy funneling mainly occurs at a timescale longer than the FRET mechanism. Moreover, the degree of energy funneling is revealed and the carrier diffusion lengths display a similar dependence on temperature, evidencing the interdomain energy funneling is dominated by CT. This work provides a significant insight into energy funneling mechanism that is important for future developments of optoelectronic devices.
Asymmetric Dieckmann Condensation towards Spirocyclic Oxindoles Catalyzed by Amino Acid‐Derived Phosphonium Salts
Authors: Yu Longhui , Liu Jun , Wang Hongyu , Xu Lijun , Wu Yufei , Zheng Changwu , Zhao Gang
Published: November 2021

An asymmetric Dieckmann condensation towards spirocyclic oxindoles and aza‐oxindoles catalyzed by amino acid‐derived phosphonium salt has been developed, which expanded the applicability of asymmetric phosphonium salt catalysis in the production of 1,3‐dicarbonyl compounds. This reaction is distinguished by its mild conditions (−20 °C), low catalyst loading (3–5 mol%), and broad substrate scope (25 examples). Control experiments revealed that both the catalyst‘s phosphonium skeleton and H‐bonding site were required. Product transformations and a gram scale experiment were also carried out.

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Rhodium(III)‐Catalyzed Direct C7‐Selective Alkenylation and Alkylation of Indoles with Maleimides
Authors: Sheng Yaoguang , Gao Yi , Duan Bingbing , Lv Mengxia , Chen Yao , Yang Mengjie , Zhou Jianmin , Liang Guang , Song Zengqiang
Published: November 2021

A versatile and efficient method for the coupling of maleimides and indoles at the C7‐position has been established under Rh(III) catalysis. The present protocol was compatible with various functional groups, diverse 3‐(indol‐7‐yl)maleimides and 3‐(indol‐7‐yl)succinimides were obtained in moderate to excellent yields by switching reaction conditions. Moreover, this method further highlights the unique practical application for the conjugation with pharmaceutically useful compounds and amino acid derivatives. To explore the mechanism of this transformation, deuteration studies and control experiments have been carried out.

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Pyrrolidine‐Catalyzed Annulations of Quinone Monoacetals with Naphthols: Synthesis of 2‐Oxabicyclo[3.3.1]nonane Skeletons, Transformations and Reaction Mechanism
Authors: Li Xiaojie , Xiao Tianyu , He Guangke , Zhu Shugao , Zhu Dunru , Shen Ruwei
Published: November 2021

Herein, we report the pyrrolidine‐catalyzed annulation reaction of p‐quinone monoacetals with naphthols at room temperature. The reaction is also extended to including 4‐hydroxycoumarin, 4‐hydroxy‐1‐methylcarbostyril, 4‐hydroxycarbostyril, and several β‐ketoesters as the nucleophiles, thereby providing a collection of bridged cyclic compounds bearing 2‐oxabicyclo[3.3.1]nonane skeletons in 41–96% yields. The reaction can be adapted to gram‐scale synthesis, and several transformations of the obtained bridged cyclic products are demonstrated for the preparation of polycyclic compounds that may find utility in related fields. Mechanism studies indicate the engagement of iminium intermediate in the reaction, and a bridged ring enamine intermediate can be observed by NMR.

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Iron‐Catalyzed Alkene Trifluoromethylation in Tandem with Phenol Dearomatizing Spirocyclization: Regioselective Construction of Trifluoromethylated Spirocarbocycles
Authors: Zhao Yilin , Wang Xue , Yao Ru , Li Chengwen , Xu Zelin , Zhang Liming , Han Guifang , Hou Jingli , Liu Yangping , Song Yuguang
Published: November 2021

In the presence of Fe(III) complex and Bipy ligand, CF3‐containing spirocarbocycles were conveniently obtained in 20–99% yields with high regioselectivity through Iron‐catalyzed trifluoromethylation of unactivated alkenes coupled with phenol dearomatizing spirocyclization.

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Biostack: Nontoxic Metabolite Detection from Live Tissue
Authors: Strakosas Xenofon , Donahue Mary J. , Hama Adel , Braendlein Marcel , Huerta Miriam , Simon Daniel T. , Berggren Magnus , Malliaras George G. , Owens Roisin M.
Published: November 2021

There is increasing demand for direct in situ metabolite monitoring from cell cultures and in vivo using implantable devices. Electrochemical biosensors are commonly preferred due to their low‐cost, high sensitivity, and low complexity. Metabolite detection, however, in cultured cells or sensitive tissue is rarely shown. Commonly, glucose sensing occurs indirectly by measuring the concentration of hydrogen peroxide, which is a by‐product of the conversion of glucose by glucose oxidase. However, continuous production of hydrogen peroxide in cell media with high glucose is toxic to adjacent cells or tissue. This challenge is overcome through a novel, stacked enzyme configuration. A primary enzyme is used to provide analyte sensitivity, along with a secondary enzyme which converts H2O2 back to O2. The secondary enzyme is functionalized as the outermost layer of the device. Thus, production of H2O2 remains local to the sensor and its concentration in the extracellular environment does not increase. This “biostack” is integrated with organic electrochemical transistors to demonstrate sensors that monitor glucose concentration in cell cultures in situ. The “biostack” renders the sensors nontoxic for cells and provides highly sensitive and stable detection of metabolites.
Highly Efficient Electrocatalytic N2 Reduction to Ammonia over Metallic 1T Phase of MoS2 Enabled by Active Sites Separation Mechanism
Authors: Liu Ruoqi , Guo Ting , Fei Hao , Wu Zhuangzhi , Wang Dezhi , Liu Fangyang
Published: November 2021

The 1T phase of MoS2 has been widely reported to be highly active toward the hydrogen evolution reaction (HER), which is expected to restrict the competitive nitrogen reduction reaction (NRR). However, in this work, a prototype of active sites separation over 1T‐MoS2 is proposed by DFT calculations that the Mo‐edge and S atoms on the basal plane exhibit different catalytic NRR and HER selectivity, and a new role‐playing synergistic mechanism is also well enabled for the multistep NRR, which is further experimentally confirmed. More importantly, a self‐sacrificial strategy using g‐C3N4 as templates is proposed to synthesize 1T‐MoS2 with an ultrahigh 1T content (75.44%, named as CNMS, representing the composition elements of C, N, Mo, and S), which yields excellent NRR performances with an ammonia formation rate of 71.07 µg h–1 mg–1cat. at −0.5 V versus RHE and a Faradic efficiency of 21.01%. This work provides a promising new orientation of synchronizing the selectivity and activity for the multistep catalytic reactions.
Polymers in Lithium–Sulfur Batteries
Authors: Zhang Qing , Huang Qihua , Hao Shu‐Meng , Deng Shuyi , He Qiming , Lin Zhiqun , Yang Yingkui
Published: November 2021

Lithium–sulfur batteries (LSBs) hold great promise as one of the next‐generation power supplies for portable electronics and electric vehicles due to their ultrahigh energy density, cost effectiveness, and environmental benignity. However, their practical application has been impeded owing to the electronic insulation of sulfur and its intermediates, serious shuttle effect, large volume variation, and uncontrollable formation of lithium dendrites. Over the past decades, many pioneering strategies have been developed to address these issues via improving electrodes, electrolytes, separators and binders. Remarkably, polymers can be readily applied to all these aspects due to their structural designability, functional versatility, superior chemical stability and processability. Moreover, their lightweight and rich resource characteristics enable the production of LSBs with high‐volume energy density at low cost. Surprisingly, there have been few reviews on development of polymers in LSBs. Herein, breakthroughs and future perspectives of emerging polymers in LSBs are scrutinized. Significant attention is centered on recent implementation of polymers in each component of LSBs with an emphasis on intrinsic mechanisms underlying their specific functions. The review offers a comprehensive overview of state‐of‐the‐art polymers for LSBs, provides in‐depth insights into addressing key challenges, and affords important resources for researchers working on electrochemical energy systems.
Printed Zinc Paper Batteries
Authors: Yang Peihua , Li Jia , Lee Seok Woo , Fan Hong Jin
Published: November 2021

Paper electronics offer an environmentally sustainable option for flexible and wearable systems and perfectly fit the available printing technologies for high manufacturing efficiency. As the heart of energy‐consuming devices, paper‐based batteries are required to be compatible with printing processes with high fidelity. Herein, hydrogel reinforced cellulose paper (HCP) is designed to serve as the separator and solid electrolyte for paper batteries. The HCP can sustain higher strain than pristine papers and are biodegradable in natural environment within four weeks. Zinc‐metal (Ni and Mn) batteries printed on the HCP present remarkable volumetric energy density of ≈26 mWh cm–3, and also demonstrate the feature of cuttability and compatibility with flexible circuits and devices. As a result, self‐powered electronic system could be constructed by integrating printed paper batteries with solar cells and light‐emitting diodes. The result highlights the feasibility of hydrogel reinforced paper for ubiquitous flexible and eco‐friendly electronics.
Wide Bandgap Interface Layer Induced Stabilized Perovskite/Silicon Tandem Solar Cells with Stability over Ten Thousand Hours
Authors: Li Yucheng , Shi Biao , Xu Qiaojing , Yan Lingling , Ren Ningyu , Chen Yongliang , Han Wei , Huang Qian , Zhao Ying , Zhang Xiaodan
Published: November 2021

The perovskite/silicon tandem solar cell (PK/c‐Si TSC) is a reasonable choice that can break through the efficiency limitations of silicon cells. Here, the p‐i‐n perovskite solar cell is conformally grown by the evaporation–solution combination technique on fully‐textured silicon heterojunction cells to realize two‐terminal PK/c‐Si TSCs. Due to the adverse effect of the residual PbI2 at the bottom of the perovskite bulk on device performance, a thermal‐evaporated CsBr thin layer is introduced between the perovskite layer and the hole transport layer to construct a gradient perovskite absorber for optimized energy level alignment, so as to improve the open‐circuit voltage and fill factor of the device. Finally, the PK/c‐Si tandem cell achieves an efficiency of 27.48% and is stable in nitrogen over 10 000 h.
Recent Advances on Electrolysis for Simultaneous Generation of Valuable Chemicals at both Anode and Cathode
Authors: Li Rui , Xiang Kun , Peng Zhikun , Zou Yuqin , Wang Shuangyin
Published: November 2021

To make efficient use of electrical energy in the whole electrocatalysis conversion process, the integrating of anode and cathode reactions plays a vital role. The combination of electrocatalytic anodic oxidation with cathodic reduction can not only maximize the return of energy investment, but also produces value‐added materials on both sides. Herein, in this review, recent advances in co‐electrolysis processes for valuable chemical production are systematically summarized. To be more specific, the popular hydrogen evolution reaction, carbon dioxide reduction reaction, nitrogen reduction reaction as well as nitrate reduction reaction integrated with anodic oxidation reactions to value‐added products, respectively are comprehensively reviewed, and then other paired electrolysis systems (especially for biomass‐based compounds) toward high‐value‐added chemical generation are discussed in detail. This review sheds light on the integration of electrocatalytic reductions and oxidation reactions to develop high‐value substances. To benefit researchers and facilitate the progress in this field, the challenges and future prospects for these integrated reactions are also proposed.
To Fluorinate or Not to Fluorinate in Organic Solar Cells: Achieving a Higher PCE of 15.2% when the Donor Polymer is Halogen‐Free
Authors: Wu Jianglin , Liao Chuang‐Yi , Chen Yao , Jacobberger Robert M. , Huang Wei , Zheng Ding , Tsai Kuen‐Wei , Li Wei‐Long , Lu Zhiyun , Huang Yan , Wasielewski Michael R. , Chang Yi‐Ming , Marks Tobin J. , Facchetti Antonio
Published: November 2021

Fluorination of the donor and/or acceptor blocks of photoactive semiconducting polymers is a leading strategy to enhance organic solar cell (OSC) performance. Here, the effects are investigated in OSCs using fluorine‐free (TPD‐3) and fluorinated (TPD‐3F) donor polymers, paired with the nonfullerene acceptor Y6. Interestingly and unexpectedly, fluorination negatively affects performance, and fluorine‐free TPD‐3:Y6 OSCs exhibit a far higher power conversion efficiency (PCE = 14.5%) than in the fluorine‐containing TPD‐3F:Y6 blends (PCE = 11.5%). Transmission electron microscopy (TEM) analysis indicates that the TPD‐3F:Y6 blends have larger phase domain sizes than TPD‐3:Y6, which reduces exciton dissociation efficiency to 81% for TPD‐3F:Y6 versus 93% for TPD‐3:Y6. Additionally, grazing incidence wide‐angle X‐ray scattering (GIWAXS) reveals that the TPD‐3F:Y6 blends are less textured than those of TPD‐3:Y6, while space‐charge limited currents reveal lower and unbalanced hole/electron mobility in TPD‐3F:Y6 versus TPD‐3:Y6 blends. Charge recombination dynamic, transient absorption, and donor–acceptor miscibility assays additionally support this picture. Furthermore, conventional architecture TPD‐3:Y6 OSCs deliver a PCE of 15.2%, among the highest to date for halogen‐free polymer donor OSCs. Finally, a large‐area (20.4 cm2) TPD‐3:Y6 blend module exhibits an outstanding PCE of 9.31%, one of the highest to date for modules of area >20 cm2.
Strategies for the Analysis of Graphite Electrode Function
Authors: Andersen Henrik Lyder , Djuandhi Lisa , Mittal Uttam , Sharma Neeraj
Published: November 2021

Since the commercialization of lithium‐ion batteries, graphite has been the uncontested material of choice as the negative electrode host structure, and it has therefore been pivotal for their ubiquitous adoption and implementation. Despite extensive research efforts dedicated to discovering and developing alternative anode material candidates, no commercially viable successor has so‐far been identified. Simultaneously, the understanding of graphite electrode function is continuously expanding, and new strategies for rationally improving performance are being explored. Here, the key challenges lie in examining the graphitic material, not only in the pure as‐prepared state, but also when formed into an electrode and during electrochemical cycling, i.e., in situ/operando. A multiscale approach is necessary to accurately relate the (de)lithiation/(de)intercalation mechanisms involved to the observed performance. The present review summarizes conventional techniques and highlights recent advances in the analytical methods used for the characterization of graphite‐based electrode structure and function. The discussion is based on examples from key recent work using innovative analytical strategies to obtain novel insight into the evolution in structure, microstructure, electronic structure, surface chemistry/composition, etc. The deeper understanding of material function gained from these innovative approaches may hold the key for the rational design of next‐generation graphite‐based or ‐inspired electrodes.
Closing the Anthropogenic Chemical Carbon Cycle toward a Sustainable Future via CO2 Valorization
Authors: Zhang Jiawei , Sewell Christopher D. , Huang Hongwen , Lin Zhiqun
Published: November 2021

Concerns over the massive increase in CO2 emissions induced by overconsumption of fossil fuels have driven the rapid development of CO2 valorization techniques. Carbon capture and utilization (CCU) technology, which emerged as a promising strategy to relieve increasing environmental concerns and create more carbon feedstocks simultaneously, hold great promise to close the anthropogenic chemical carbon cycle. Herein, recent breakthroughs related to the two predominant techniques involved in returning CO2 into a useful state, namely CO2 capture and CO2 conversion are systematically overviewed. Initially, CO2 capture principles, recent advances, as well as future challenges of state‐of‐the‐art absorbents/adsorbents and membrane separation technology are summarized. Furthermore, innovative catalysts related to the CO2 conversion technologies (including thermo‐driven CO2 hydrogenation, photo‐and electrochemical CO2 reduction, and enzymatic CO2 conversion) are discussed, emphasis is focused on the catalytic performance, design principles, and economic efficiency. Finally, a perspective regarding the future research opportunities toward CCU technologies is provided. This review aims to stimulate innovation and accelerate interdisciplinary integrations toward CCU related technologies via a discussion of fundamental mechanisms, recent breakthroughs, current associated difficulties as well as future directions.