bluuebunny/crossref_metadata_2025 huggingface dataset:
Equilibrium Swollen EPDM Studied Using Photon Correlation Spectroscopy
Authors: Kabir M. Hasnat , Khosla Ajit , Furukawa Hidemitsu
Published: February 2020

Scanning Microscopic light scattering is a kind of photon correlation spectroscopy, which was used to study the internal homogeneity of cross-linked EPDM. The samples were swollen with toluene for several days to insure the equilibrium state. The equilibrium swollen samples with toluene were characterized by SMILS, laboratory dynamic light scattering equipment. The dynamic properties of the EPDM samples were studied. The cooperative diffusion coefficient Dcoop was determined which comes from Brownian motion. The correlation length of internal three dimensional network structures was done from Stokes-Einstein relation, which actually represents the mesh size of polymer network. Experimental results show that the network size decreases as a function of the cross - linked amount. It is observed that the variations of Dcoop with cross-linked concentration. The SMILS data of mesh size were compared with those calculated from the swelling measurements. It is found the good agreement between both data.
3D Printing of Electrically Conductive Hybrid Organic-Inorganic Materials
Authors: Shah Shreyas , Shiblee MD Nahin Islam , Basher Samiul , Rahman Julkarnyne M. Habibur , Nagahara Larry A , Thundat Thomas , Sekhar Praveen K. , Kawakami Masaru , Furukawa Hidemitsu , Khosla Ajit
Published: February 2020

We present preparation, characterization, and 3D printing of electrically conductive Acrylonitrile butadiene styrene (ABS) polymer. The electrically conducting ABS was prepared by doping carbon fibers (150μm in length, acquired from Nippon Graphite Corporation), at 200 ̊C by using a thermo-plasto mill, with different weight percentages (wt%) of carbon fibers in ABS polymer matrix. Electrical conductivity of samples with following weight percentages (10, 15, 25, 50 and 60 wt% carbon fibers in ABS polymer matrix) were measured using 4-point probe method [1, 2], with a result that percolation threshold occurs at 25wt%, as shown in Fig 1. SEM analysis (Fig. 2) shows uniform dispersion of carbon fibers in ABS polymer matrix, when compared to previously reported methods [3, 4]. Electrical conductivity of 1.013S/m is observed at 50 wt %. We employed melt extrusion technique in order to fabricate cylindrical filament with a diameter of 1.75 mm. A standard Fused Deposition Modeling (FDM) type printer (Makerbot) was used to print the developed filament (Fig. 3). The developed ABS electrically conductive composite is being applied in applications, such as 3D printing of wires, circuits, sensors, resistors, heaters, robotics, MEMS and microfluidics devices.

References:

Khosla, A. (2011). Micropatternable multifunctional nanocomposite polymers for flexible soft MEMS applications(Doctoral dissertation, Applied Science: School of Engineering Science). http://summit.sfu.ca/item/12017

Khosla, A. (2012). Nanoparticle-doped electrically-conducting polymers for flexible nano-micro Systems. The Electrochemical Society Interface, 21(3-4), 67-70. doi: 10.1149/2.F04123-4if

Gray, B. L., & Khosla, A. (2010). Microfabrication and applications of nanoparticle doped conductive polymers. Nanoelectronics: Nanowires, Molecular Electronics, and Nanodevices, 227.

Khosla, A., & Gray, B. L. (2010, March). Fabrication of multiwalled carbon nanotube polydimethylsiloxne nanocomposite polymer flexible microelectrodes for microfluidics and MEMS. In Proc. SPIE (Vol. 7642, p. 76421V). doi: 10.1117/12.847292

Figure 1
Electrochemical Detection of Tricresyl Phosphates in Gas
Authors: Zhou Lang , Dean Patrick J. , Chin Bryan A. , Simonian Aleksandr L.
Published: February 2020

Tricresyl phosphate (TCP) is a class of neurotoxic organophosphate cholinesterase inhibitors, exposure to which may induce nausea, vomiting, diarrhea and abdominal pain. Despite of its acute toxicity, TCP is widely used in industrial applications, including flame retardants, and plasticizers. Many military and commercial aircrafts have employed hydraulic fluids containing TCP organophosphates additive since the 1970s. Potentially TCP could be released into the cabin air environment during oil leakage on aircraft hydraulic systems. Exposure to passengers and crew occurs mainly through ingestion, inhalation of aerosols, and dermal sorption. In this study, an automatic electrochemical detection system was developed to measure the TCP in gas. TCP was absorbed and hydrolyzed by an alkaline alumina column, to obtain hydrolysates that are electrochemically active, i.e. cresol, and then washed out by buffer for direct electrochemical detection. After each detection, NaOH solution was used to regenerate the column. The effects of different experiment conditions were investigated such as elution time, alumina type, the composition of regeneration solution, flow rate, temperature, etc. Through the optimization, an automatic TCP detection device was obtained with features of high sensitivity, regeneration capability and portability, which could be utilized in site test of cabin.
Silicon Nanowire Based Sensors By Using Nickel-Oxide Membrane for Sarcosine Sensing
Authors: Roy Anisha , Maikap Siddheswar
Published: February 2020

Now-a-days different kinds of bio-analytes sensing like creatinine [1], dopamine, uric acid [2], H2O2 [3] and so on using different methods like metal-insulator-metal structure, amperometric, cyclic voltammetry [2], colorimetric, capacitor-voltage [3] method has huge demand in bio-chemical industry. Sarcosine is also one type of bio-analyte that remains in human urine. Sreekumar et al. [4] have marked sarcosine as prostate cancer bio-marker. A lower range of 50 pM sarcosine is reported by Samanta et al. and Z. Heger et al. with GeOx and paramagnetic nanoparticles respectively [5-6]. In presence of sarcosine oxidase (SOx) enzyme, sarcosine produces formaldehyde (HCHO), glycine and H2O2 [5-6]. Sarcosine sensing is realized by detecting this product H2O2. We have detected sarcosine as a prostate cancer bio-marker by fabricating silicon nanowire based sensors in electrolyte-insulator-semiconductor structure (EIS). The silicon nanowires (SiNWs) are etched in chemical etching method (Fig. 1) as it has low cost, quick and easier process among the well known SiNWs growth processes like CVD, laser ablation, MBE [7], and so on. Etching was performed on n-type Si wafer in 0.02 M AgNO3 and 5 M aqueous HF solution. A 10-nm thick SiO2 layer was grown in thermal oxidation method and 300-nm thick back sides Al contact was performed by thermal evaporator. Then, a 2 nm-thick NiOx layer was deposited on it by RF sputtering. Finally, the device was patterned in photolithography and attached to printed circuit board. The SiNWs based sensors with NiOx layer show improvement in sensitivity (̴ 49 mV/pH), linearity (̴ 99.78%), drift (̴ 3.4 mV/hr) and hysteresis (̴ 3.4 mV) characteristics due to increase in surface sites. The NiOx sensing membrane shows novel nature on SiNWs as well as the chemically etched NWs are rough on surface. These results enhance the catalytic activity of the NiOx membrane. In practice planar SiO2 based sensors cannot show H2O2 sensing due to its stoichiometric structure. But the SiNWs sensor is capable of 1 nM H2O2 sensing because the Ni2+oxidation state changes to Ni3+. This sensor is also able to sense sarcosine as a prostate cancer biomarker. In presence of 25 units SOx it has detected 1 nM sarcosine with a higher shift towards negative direction (Fig. 2) because of NiOx work function changes. This novel sensor paves a way to detect prostate cancer at early state of a patient in near future.

Acknowledgement: This work was supported by Ministry of Science and Technology (MOST), Taiwan under contract number: 105-2221-E-182-002.

References

1) S. Roy et al., J. Alloys Comp., vol. 726, 2017, p. 30-40.

2) G. A. Tiget al., J. Appl.Electrochem., vol. 47, 2017, p. 607.

3) S. Chakrabarti et al., Phys. Chem. Chem. Phys., vol. 19, 2017, p. 25938-25948.

4) A. Sreekumar et al., Nature, vol. 457, 2009, p. 9810-8914.

5) S. Samanta et al., Sci. Rep., vol.7, 2017, p. 11240.

6) Z. Heger et al., Sci. Rep., vol. 5, 2015, p. 8868.

7) V. Schmidt et al., Adv. Mater., vol. 21, 2009, p. 2681-2702.

Figure 1
Non-Faradaic Affinity Based Biosensor for Enhanced Detection of Biomarkers in Sweat Using Room Temperature Ionic Liquids
Authors: Jagannath Badrinath , Muthukumar Sriram , Prasad Shalini
Published: February 2020

In this work, the role of room temperature hydrophilic ionic liquids in enhancing the biosensing performance of affinity based electrochemical biosensors in human sweat was investigated. Room temperature ionic liquids (RTILs) consist of an organic cationic and inorganic anionic moieties, with the kosmotropic nature of the anionic moieties providing more stability to the capture probe. The biosensing performance of the immunosensor with capture probe antibody in 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM[BF4]) and choline dihydrogen phosphate (Choline[DHP]) were compared to capture probe in aqueous buffer. Non-faradaic interfacial charge transfer mechanism was used for evaluating the formation of room temperature ionic liquids (RTILs)/ aqueous human sweat interface. Compact electrical double layers (EDL) are formed by the ionic moieties around the antibodies for enhancing the stability of the antibody capture probes. The stability of the capture probe for biosensing evaluated through zeta potential, indicated the electrostatic repulsion of the RTIL charged moieties encompassing the antibodies, thus preventing any aggregation. The zeta potential measurements also indicated that the antibody in RTIL does not reach the isoelectric point (IEP) even upon interaction with varying pH of sweat. In this study, non-faradaic electrochemical impedance spectroscopy was employed to evaluate the biosensing performance of an affinity based biosensor for the detection of interleukin-6 and cortisol. The EDL interface of the antibody/ionic liquid and sweat buffer interface was modeled using an equivalent circuit for analyzing affinity based biosensing at hybrid electrode/ionic liquid- aqueous sweat buffer interface guided by the choice of the ionic liquid. Interleukin-6 (IL-6) and cortisol that occur in human sweat were detected using the developed affinity based immunoassay. The limit of detection (LOD) of IL-6 in human sweat obtained using capture probe in aqueous phosphate buffered saline was 20 pg/mL. However, a much lower LOD of 0.2pg/mL was obtained in both ionic liquids. Similarly, cortisol of 20 ng/mL was obtained as detection limit using capture probe in aqueous but a better LOD of 0.1 ng/mL was obtained using both the ionic liquids. The better sensing performance in ionic liquids is primarily driven by the enhancement of the double layer capacitance resulting from the formation of compact EDLs. The cross-reactivity studies indicated a better performance of IL-6 detection using Choline[DHP]. On the contrary, an enhanced signal response was obtained for cortisol using cortisol antibody in BMIM[BF4]. The cross-reactivity studies for cortisol detection using antibody in BMIM[BF4] did not show any signal response to cross-reactive molecules.
3D Printed Shape Memory Hydrogels for Soft Robotics
Authors: Shiblee MD Nahin Islam , Ahmed Kumkum , Khosla Ajit , Furukawa Hidemitsu
Published: February 2020

Hydrogels possess three-dimensional polymeric networks and capable of absorbing large amounts of water or biological fluids. Due to their high water content, porosity and low friction they closely simulate natural living tissue. The properties of a polymer gel depend on the chemical structures of the component molecule and can be controlled or tuned by external stimuli such as heat, optics, solvent, and pH. Shape-memory gels (SMGs) are unique materials that have the ability to return from a temporary deformed state to their permanent i.e. original shape induced by an external stimulus like temperature change. Poly(dimethyl acrylamide-co-stearyl acrylate) (DMMA-co-SA)-based SMGs [1] show thermoresponsive shape memory behavior when temperature was raised above 40 °C. Although being a hydrogel they are mechanically very strong along with good flexibility and transparency. In this work, we applied stereolithographic (SLA) process to fabricate DMMA-co-SA SMGs using our customized 3D printer named as SWIM-ER. Using SWIM-ER we were able to print sample models like gel sheets and tubes of SMGs that were transparent, flexible and strong. However, printing of SMGs was not an easy task due a number of issues like sample polymerization inhibition, turbidity, swelling during printing and shape deformation. We critically maintained these conditions and resulted SMGs were compared with that of conventionally synthesized SMGs to find out the effect of printing on the mechanical and swelling properties. Finally, we analyzed the limitation and potential of 3D printing process and discussed a possible approach for application of 3D printed SMGs in soft actuators and sensors.

Reference:

[1] Amano, Y; Hidema, R; Gong, J; Furukawa, H. Chem Lett.,41, 1029-1031 (2012)
3D Printed Wearable Glucose Sensors
Authors: Song Yang , Nesaei Sepehr , Du Dan , Gozen Arda , Lin Yuehe
Published: February 2020

School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164

Wearable biosensor technology has attracted intensive research interests since it provides accurate monitoring of physiological samples for diagnosing, managing and treating disease and monitoring individual physical health without extracting blood sample. The most common detection technique depends on frequently correcting blood samples for measurement or continuous monitoring devices, which are expensive, painful and inconvenient. Thus, extensive efforts have been devoted to develop noninvasive sensors that rely on electrical and electrochemical techniques. Mechanical properties are important to wearable devices since they directly contact with human skin, which should need the Young’s modulus around 130–657 kPa [1, 2]. To meet this requirement, electrode materials should hold high viscosity at low-shear rates (103 to 105 Pa s) with shear thinning and viscoelastic behavior with high extensional relaxation times (>1 s), limiting their processing using common electrode fabrication technology. 3D printing technologies typically can process the materials with high concentration as well as high viscosity and shear-thinning behavior; utilize stretchable polymer composites with conductive compounds and have ability to construct complex, customized 3D geometries [3-4]. It can easily employ thin conductive films on stretchable substrates.

In our study, our micro additive manufacturing of wearable glucose/lactase biosensor shows the advantage over conventional methods, including: (1) feasible design of objects with higher levels of integrate enzyme/electrode co-production (layer by layer), and (2) appropriate for modifications due to fine resolution and significant materials saving. This will enable us to achieve high conductivity and physiochemical stability of electrode on flexible substrates as well as thinner, higher aspect ratio structures with ideal three-dimensional stacking. We found that the sensitivity of our wearable sensor was much higher than that of traditional printed biosensor (~ 3 folds) due to the extreme fine and less defected surface area printed by DIW technique, which resulting in uniform surface carbon nanoparticle distribution. Besides, our wearable sensors show excellent reproducibility and long-time stability.

Reference

(1) Guo S Z, Qiu K, Meng F, et al. 3D Printed Stretchable Tactile Sensors[J]. Advanced Materials, 2017.

(2) Muth J T, Vogt D M, Truby R L, et al. Embedded 3D printing of strain sensors within highly stretchable elastomers[J]. Advanced Materials, 2014, 26(36): 6307-6312.

(3) Nesaei S, Rock M, Wang Y, et al. Additive Manufacturing With Conductive, Viscoelastic Polymer Composites: Direct-Ink-Writing of Electrolytic and Anodic Poly (Ethylene Oxide) Composites[J]. Journal of Manufacturing Science and Engineering, 2017, 139(11): 111004.

(4) Truby R L, Lewis J A. Printing soft matter in three dimensions[J]. Nature, 2016, 540(7633): 371-378.
Smartphone Based Microanalytical Device for Immunoassay of 2,4-D Determination
Authors: Wang Yijia , Du Dan , Lin Yuehe
Published: February 2020

Onsite rapid detection of herbicide and herbicide residuals in environmental and biological specimens is important for agriculture, environment, food safety, and health care.1-2 Traditional method for herbicide detection requires expensive laboratory equipment and a long turn-round time.3-5 In this work, we developed a single-stripe microtiter plate smartphone colorimetric device for rapid and low-cost in-field test (Figure). This portable smartphone platform is capable of screening 8 samples in a microplate single-stripe. The device was validated with good sensitivity. Reliable linear relationship for detection were obtained comparing with microplate reader. This optosensing device were put into practical application for 2,4-D detection. Different concentration of 2,4-D from 80 ng/mL to 1 ng/mL were detected by the smartphone device, good linear relationship was obtained. The detection limit is down to 1 ng/mL which is lower than ELIASA reader. For real ground water sample and blood sample, it gives a good recovery rate and good linear relationship. It validated that the smartphone optical sensing platform is eligible for onsite rapid and low-cost detection of herbicide in practical samples for environmental evaluation and biological monitoring.

Figure . (a) Three-dimensional structure of the smartphone based single stripe microplate reader. (b) Linear analysis of 2,4-D under the best experiment condition.

References：

McDuffie, H. H.; Pahwa, P.; McLaughlin, J. R.; Spinelli, J. J.; Fincham, S.; Dosman, J. A.; Robson, D.; Skinnider, L. F.; Choi, N. W. Cancer Epidemiol. Prev. Biomark. 2001, 10 (11), 1155–1163.

Takashima-Uebelhoer, B. B.; Barber, L. G.; Zagarins, S. E.; Procter-Gray, E.; Gollenberg, A. L.; Moore, A. S.; Bertone-Johnson, E. R. Environ. Res. 2012, 112, 171–176.

Hughes, D. L.; Ritter, D. J.; Wilson, R. D. J. Environ. Sci. Health Part B 2001, 36 (6), 755–764

Jia, J.-L.; Xu, H.-H.; Zhang, G.-R.; Hu, Z.; Xu, B.-Q. Nanotechnology 2012, 23 (49), 495710.

Wang, X.; Yu, J.; Wu, X.; Fu, J.; Kang, Q.; Shen, D.; Li, J.; Chen, L. Biosens. Bioelectron. 2016, 81, 438–444.

Figure 1
Correlation of Surface Free Energy and Hydrophobicity of Aluminum Alloy with and without Corrosion Resistant Organic Coatings
Authors: Nardeli Jéssica Verger , Benedetti Assis Vicente , Fugivara Cecilio Sadao
Published: February 2020

Crambe oil, castor oil and two different proportions of crosslinking agent (Trimethylolpropane) were made to react to form two types of hydroxylated polyesters. Hexamethylene diisocyanate was reacted with castor oil and oxygenated organic compounds to produce a prepolymer. The polyesters were combined with prepolymer in two different proportions to result four polyurethane resins which were applied on AA1200 aluminum alloy surface, giving to the aluminum alloy high corrosion resistance in 3.5% NaCl aqueous solution at 25 oC [1]. This study deals with the wetting characteristic of bare and coated aluminum surfaces by measuring the dynamic contact angle. The determination of the contact angle has helped to interpret the hydrophobic and hydrophilic character of the surface. Surface free energy components (γs, γs
p, γs
d), and adhesion work (WA) values were calculated by the OWRK method (Owens-Wendt-Rabel and Kaelble) according to the contact angle (Ө) data. For comparison, three liquids with different polarities (distilled water, ethylene glycol and ethanol) were used on the surface of the aluminum alloy with and without organic coating. The results of the contact angle measurements allowed to evaluate the wettability of the substrate surface (with and without coating) and to estimate the free surface energy. The greater the contact angle of the liquid in the organic coating, the more hydrophobic the surface is, and consequently less susceptible to wetting and corrosion. Compared to the substrate (AA1200 aluminum) contact angle of 102.4°, the coatings are less hydrophobic (PEC2 H3 1:2 contact angle of 73.6° and PEC2 H3 1:3 equal to 82.0°). Already the coatings have higher surface energy: substrate (22.2 mN/m), PEC2 H3 1:2 (31.3 mN/m) and PEC2 H3 1:3 (25.4 mN/m). Changes in contact angle and surface free energy are associated with the possibility of forming more hydrogen bonds with the coating.

Reference

[1] J.V. Nardeli, D.V. Snihirova, C.S. Fugivara, M.F. Montemor, E.R.P. Pinto, Y. Messaddecq, A.V. Benedetti, Localised corrosion assessement of crambe-oil-based polyurethane coatings applied on the ASTM 1200 aluminum alloy, Corros. Sci. 111 (2016) 422-435.

Acknowledgement

Process FAPESP: 2015/10554-9.
Noncovalent Chemistry of SWNTs Inside-Out
Authors: Perez Emilio M
Published: February 2020

Here, we present novel strategies to interface molecules and single-walled carbon nanotubes (SWNTs).

In particular, we will present the synthesis of mechanically interlocked derivatives of SWNTs (MINTs), which are rotaxane-type materials, the first example of, a 0D-1D mixed dimensional heterostructure interfaced through the mechanical bond (Angew. Chem. Int. Ed. 2014, Chem. Commun. 2015, Chem. Sci. 2017, Chem. Eur. J. 2017). We will also show that the effect of the mechanical bond on the properties of SWNTs is unique, and clearly different from the noninterlocked, supramolecular compounds (Nanoscale 2016, ACS Nano 2016)

We will also show that the encapsulation of viologen derivatives into metallic single-walled carbon nanotubes (SWNTs) results in the opening of a band gap, making the SWNTs semiconducting. Raman spectroscopy, thermogravimetric analysis, and aberration-corrected high-resolution transmission electron microscopy confirm the encapsulation process. Through the fabrication of field-effect transistor devices, the change of the electronic structure of the tubes from metallic to semiconducting upon the encapsulation is confirmed (Angew. Chem. Int. Ed. 2017).

In summary we present two novel noncovalent strategies to functionalize the outside and the inside of SWNTs, with direct consequences to their electronic properties.
Dramatic Nano-Fluidic Properties of Carbon Nanotube Membranes As a Platform for Programmable Transdermal Drug Delivery
Authors: Hinds Bruce J
Published: February 2020

Carbon nanotubes (CNT) have three key attributes that make them of great interest for novel membrane applications 1) atomically flat graphite surface allows for ideal fluid slip boundary conditions for 10,000 fold faster fluid flow 2) the cutting process to open CNTs inherently places functional chemistry at CNT core entrance for gatekeeper activity and 3) CNT are electrically conductive allowing for electrochemical reactions and application of electric fields gradients at CNT tips. Pressure driven flux of a variety of solvents (H2O, hexane, decane ethanol, methanol) are 4-5 orders of magnitude higher than conventional Newtonian flow [Nature
2005, 438, 44] due to atomically flat graphite planes inducing nearly ideal slip conditions. However this is eliminated with selective chemical functionalization [ACS Nano
2011 5 3867-3877] needed to give chemical selectivity. These unique properties allow us to explore the hypothesis of producing ‘Gatekeeper’ membranes that mimic natural protein channels. With anionic tip functionality strong electroosmotic flow is induced by unimpeded cation flow with similar 10,000 fold enhancements [Nature Nano
2012 7 133-39]. With enhanced power efficiency, carbon nanotube membranes were employed as the active element of a switchable transdermal drug delivery device that can facilitate more effective treatments of drug abuse and addiction [PNAS . 2010 107 11698]. Due to extremely efficient electroosmosis in the CNT conduits, a watch battery coin cell is able to operate for over 7 days nicotine delivery switching between target dosing of static diffusion transdermal patch and that of nicotine gum. Using optimal fabrication and operational conditions (pH8, -1.5V), ON nicotine fluxes of 5.9 µmoles/cm2/h and ON/OFF ratio of 15 were achieved. This exceeds the demand for nicotine cessation treatment 1.1 µmoles/cm2/h (4mg gum) and ON/OFF ratio (3.6-11) and allows for an active patch area of 4.1cm2, compared to 22cm2 of commercial patches. Power consumption per dose rate of 120 μW/cm2-(μmol/cm2-s) was achieved. Use of electroosmosis in CNTs gives high power efficiencies for compact battery sources. For treatments with a continuous 21mg/24h delivery (commercial patch), a watch battery can last 20.5 days pumping. For early stage treatments with patch and 10x4mg gum dosing, battery life of 7.1 days is expected, well within useful device replacement periods.The systems is demonstrated to work with smart-phone enabled counseling app to form a dosing calendar that is wirelessly transmitted to Bluetooth microcontroller.
(Invited) Synthesis and Isolation of Scandium-Uranium Based Endohedral Fullerenes
Authors: Torres Maria A Gomez , Murillo Jesse , Cai Wenting , Echegoyen Luis
Published: February 2020

Actinide Endohedral Metallofullerenes (EMFs) represent a poorly explored and potentially useful branch of EMF chemistry. Recently there have been successes in producing mono and di-uranium EMF species1 but no mixed metal uranium-based endohedral fullerenes have been reported. The incorporation of scandium oxide and reactive gases such as NH3, CH4 and H2 in the Krästschmer – Huffmann modified DC Arc Discharge synthesis method allowed us to significantly increase the yield of two specific mixed metal EMF including a carbide and a nitride di-scandium uranium clusters. The synthesis, isolation and fully characterization of the Sc2UC@C80 and Sc2UN@C80 compounds will be reported in this work.

1 W. Cai, R. Morales-Martinez, X. Zhang, D. Najera, E. L. Romero, A. Metta-Magana, A. Rodriguez-Fortea, S. Fortier, N. Chen, J. M. Poblet and L. Echegoyen,
Chem. Sci.
, 2017, 8, 5282-5290.

Figure 1
(Invited) Lock-in Thremography of Carbon Nanotube Composites and Graphene
Authors: Okazaki Toshiya
Published: February 2020

Lock-in thermography (LIT) is a non-destructive and fast electrical characterization method of large-area samples, and it has high spatial resolution. Detection of Joule heating in a biased device enables local structures to be imaged without the influence of heat broadening in a short acquisition time. Furthermore, because of its wide field of view, typically from sub-millimetre to sub-centimetre, one LIT image can characterize local structures in large samples. For instance, this method has been used to check for local structural failures in large-scale semiconductor devices such as integrated circuits and solar cells. In this talk, we present LIT imaging of carbon nanotube (CNT) network paths in a centimetre-scaled CNT composite at micrometre resolution. These results strongly suggest that LIT is a fine resolution tool for quickly visualizing local structures in conductive materials having large areas. Furthermore, the electrical characterization of a large CVD graphene sheet by the LIT technique is also presented. It is shown that LIT successfully visualizes the difference in electrical resistance caused by local defects as inhomogeneous thermal radiation.
Processing and Manufacturing High Performing Polymer:Ceramic Solid Electrolytes
Authors: Hatzell Kelsey B , Harkey Brice , Dixit Marm , Shen Fengyu
Published: February 2020

Scalable manufacturing and processing of high-aspect ratio multi-material solid-state electrolytes are important for advanced energy storage and conversion systems. Recently, there has been a push toward all solid-state batteries to eliminate flammability issues in portable electronics. Several solid conductors exist and broadly fall into two material categories: (1) polymers and (2) ceramics. Polymer ionic conductors are advantageous because they can be manufactured easily into thin films, are mechanically robust, and flexible. However, polymer conductors have lower ionic conductivities when compared with their ceramic counterpart. Ceramic conductors boast outstanding ionic conductivities (>10 mS/cm) but processing the electrolyte into thin films (50-100μm) for efficient device integration still remains a challenge because of the brittle nature of the ceramic. There have been a few studies which have investigated a hybrid approach which combines the polymer and ceramic into a composite electrolyte1,2,3. Fundamentally, if achieved, the polymer/ceramic electrolyte could be an effective means for meeting manufacturing requirements for battery systems. Herein, we focus on understanding and building structure-processing-property relationships for scalable manufacturing of high performing polymer/ceramic composite electrolytes. Colloidals suspensions composed of LLZO, PEO, and a range of solvents are explored as inks systems for advanced printing applications4,5. A range of electrolyte architectures are examined for fundamental transport properties and electrochemical performance metrics and synchrotron nanotomography6 is used to discern the local structure of the ceramic within the polymer.

[1] Yang, Ting, et al. "Composite Polymer Electrolytes with Li7La3Zr2O12 Garnet-Type Nanowires as Ceramic Fillers: Mechanism of Conductivity Enhancement and Role of Doping and Morphology." ACS applied materials & interfaces 9.26 (2017): 21773-21780.

[2] Zheng, Jin, and Yan Yan Hu. "New Insights into Compositional Dependence of Li-Ion Transport in Polymer-Ceramic Composite Electrolytes." ACS applied materials & interfaces(2018)

[3] Zheng, Jin, et al. "Li-ion transport in a representative ceramic–polymer–plasticizer composite electrolyte: Li 7 La 3 Zr 2 O 12–polyethylene oxide–tetraethylene glycol dimethyl ether." Journal of Materials Chemistry A 5.35 (2017): 18457-18463.

[4] Hatzell, Kelsey B., et al. "Understanding inks for porous-electrode formation." Journal of Materials Chemistry A 5.39 (2017): 20527-20533.

[5] Dixit, Marm B., et al. "Catalyst Layer Ink Interactions That Affect Coatability." Journal of The Electrochemical Society165.5 (2018): F264-F271.

[6] Hatzell, Kelsey B., et al. "Direct observation of active material interactions in flowable electrodes using X-ray tomography." Faraday discussions 199 (2017): 511-524.
Microsized Pyrite Used As Cathode Material to Improve the Electrochemical Performance of Thermal Battery
Authors: Zhaotang Yang
Published: February 2020

Influences of particle sizes on the discharge performances of microsized pyrite has been investigated, 15µm ~30µm 50µm ~75µm and 100µm ~150µm pyrite samples were manufactured. Single cell thermal batteries were fabricated for microsized pyrite evaluation. The cells were tested at 400 oC and 500 oC under baseline loads of 0.2 A/cm2 and 0.5 A/cm2 respectively, to evaluate the influences of temperature on the electrochemical performance of a thermal battery. Pulse current discharges were also used to test the discharge performance of the single cell thermal battery with different pyrite particle sizes. The results showed that cells with smaller pyrite particles had higher voltage plateau and larger specific capacities, were able to sustain higher current densities than cells with larger pyrite particle sizes. The pulse current test under 400 oC showed that the cell cannot afford the current, and the 15µm ~30µm pyrite thermal battery own the largest discharge current, which may be due to the large contact between the pyrite and the electrolyte. 8-cell thermal batteries were used to conduct the discharging test at 0.2 A/cm2 0.5 A/cm2 and pulse current conditions, which revealed that battery with 15µm ~30µm pyrite cathode had higher votage plateau and larger specific capacity than the 100µm ~150µm ones. At 0.5 A/cm2 discharge conditions, the power densities of the 15µm ~30µm pyrite thermal battery stacks is 12.5% higher than that of the 100µm ~150µm ones. Through the investigation of the electrochemical performance of the 15µm ~30µm pyrite thermal battery, they are suitable for thermal batteries discharging at large current densities.

Figure 1
The Effect of Concentration on Electron Transfer Kinetics for 9,10-Anthraquinone-2,7-Disulfonic Acid (AQDS) Its Impact on Aqueous Redox Flow Battery Performance
Authors: Wiberg Cedrik , Wang Ergang
Published: February 2020

With the recent great increase in utilization of renewable energy technologies such as wind turbines and solar cells, the need for environmentally friendly large-scale energy storage has also increased. Aqueous Organic Redox Flow Batteries (AqORFBS) are considered a promising technology for a new generation of grid-connected storage devices due to the possibility to decouple power output and capacity, inexpensive active material utilization, cheap aqueous electrolyte and ease of maintenance. One of the top-performing molecules for the negative electrolyte for AqORFBS is 9,10-Anthraquinone-2,7-Disulfonic Acid (AQDS) owing to its chemical stability, high solubility, low reduction potential and fast kinetics.

Building off of previous work[1], where AQDS was found to dimerize in aqueous solution and that the electrochemical reaction was impeded at higher concentrations, this study employed cyclic voltammetry and rotating disk electrode voltammetry to evaluate the electron transfer kinetics over a range of AQDS concentrations in both a 1 M sulfuric acid electrolyte and a 1 M pH 10 sodium carbonate buffered electrolyte. It was found that both the diffusion coefficient as well as the kinetic parameters of the electron transfer reaction changed with concentration of AQDS in the investigated range of 1-50 mM, with the strength of the effect depending on the choice of electrolyte. AQDS, along with a multitude of other organic molecules have been characterized electrochemically in regards of their suitability for redox flow batteries, but almost always at concentrations of no more than a few mM, which is likely not characteristic for the final application which often employs concentrations of upwards of 2 M[2]. Thus, this work points out the importance of taking concentration effects into account when considering the performance of a molecule for full-scale redox flow batteries.

Carney, T. J., et al. (2017). "Concentration-Dependent Dimerization of Anthraquinone Disulfonic Acid and Its Impact on Charge Storage." Chemistry of Materials 29(11): 4801-4810.

Pan, F. and Q. Wang (2015). "Redox Species of Redox Flow Batteries: A Review." Molecules 20(11): 20499-20517.
Solid Electrolyte, Flexible Li-ion Fiber Batteries for Compliant Energy Storage and Wearable Applications
Authors: Skorobogatiy Maksim , Qu Hang , Lu Xin
Published: February 2020

In my talk, I would present advances in fabrication of the solid electrolyte-based flexible li-ion fiber batteries, as well as their numerous potential applications in compliant energy storage and wearable devices. In particular, I would detail fabrication of the fiber-shaped lithium ion batteries assembled by twisting a cathode filament together with an anode filament. The cathode filament is fabricated by depositing a LiFePO4 (LFP)-composite layer onto a steel-filled polyester conductive thread (SPCT). As anode filaments, we propose several scenarios including a Li4Ti5O12 (LTO)-composite coated SPCT (dip-and-dry deposition), a tin-coated SPCT (PVD deposition) as well as a bare tin wire. An electrolyte composite layer consisting of LiPF6 and polyethylene oxide is then deposited onto both the anode and cathode filament before the battery assembly. To characterize the electrochemical and mechanical properties of the proposed batteries, we performed charge-discharge tests with different C-rates, electrical impedance tests and mechanical bending tests. The fabrication of the proposed LIBs is simple and cost-effective, as compared to the fiber-shaped LIBs using carbon nanotube fibers. Moreover, the reported LIBs are well suitable for the wearable applications as they feature all-solid electrodes and electrolyte, unlike the majority of other currently existing LIBs that utilize liquid organic solution-based electrolytes that may cause leakage and cause safety concerns. Among other advantages of the proposed LIB are light weight, ease of fabrication, high specific capacitance, high energy density, and good durability.
Impacts of Kaolin on the Thermal and Electrochemical Properties of Ternary Eutectic Molten Carbonate Electrolyte in the Direct Carbon Fuel Cell (DCFC)
Authors: Moradmand Simin , Allen Jessica A , Donne Scott W
Published: February 2020

Coal is the second largest energy resource used for electricity production in the world and is expected remain unchanged through 2030. The main problem of using coal in conventional combustion power plants is serious environmental pollution due to CO2 emissions. In this context, electrochemical conversion of solid carbon to generate electricity is one of the most efficient technologies using liquid electrolyte at high temperature which is environmentally friendly.

Raw coal as a fuel has some advantages and disadvantages in terms of mineral impurities inhabited in the coal which affect the DCFC performance. Kaolin is a common mineral found in coal fuels which has an advantage over other impurities. It was demonstrated that clay impurities in the coal such as kaolin and montmorillonite react catalytically to enhance graphite oxidation in a half-cell set up DCFC and improve the cell performance [1]. Although other impurities such as alumina, anatase and pyrite have limited impacts on the electrochemical oxidation of graphite, quartz was presented a decline in the current density of electro-oxidation of graphite. Thermal investigation of different coal impurities into ternary eutectic carbonate mixture has been done to show the impacts of these impurities on the melting process and kinetics of the melting process [2]. However it isn’t obvious yet what the impacts of these impurities have on the electrochemical performance of the cell and which disruption or modification will happen with addition of them on eutectic carbonate mixtures.

In this work different ratios of kaolinite mineral were purposely added to the ternary eutectic carbonate electrolyte to investigate the thermal properties of the mixture and its melting behaviour. Particularly, DTA data were analysed in terms of changing melting temperature of the mixture and the determination of activation energy using different heating rates to asses these effects.

The effect of kaolinite on the half-cell performance of a DCFC was also examined by adding kaolinite with different ratios into the eutectic carbonate electrolyte. The OCP, current density and polarization performance have been measured for the half-cell set up and results compared for different ratios of kaolinite and pure eutectic.

Reference:

1-Tulloch, J.; Allen, J.; Wibberley, L.; Donne, S. et al. Influence of selected coal contaminants on graphitic carbon electro-oxidation for application to the direct carbon fuel cell. J. Power Sources 2014, 260,140−14910.1016/j.jpowsour.2014.03.026

2-M.J. Glenn, J.A. Allen, S.W. Donne Thermal investigation of a doped alkali-metal carbonate ternary eutectic for direct carbon fuel cell applications Energy Fuels, 29 (8) (2015), pp. 5423-5433
Electrochemical Performance of Secondary Al Battery Via Various Anodic Material
Authors: Huang Mao-Chia , Chiang Chien-Chih , Yang Chang-Chung , Chang Wen-Sheng
Published: February 2020

For recent years, secondary Al battery become a popular topic due to its low-cost, nonflammable, ultra-fast charge and discharge, environmental-friendly, and long cycle life. So many advantages made Al batteries have considered as a potential candidate to replace lead-acid battery for light electric vehicles and grid-scale energy storage devices. In present study, we prepared a homemade ionic liquid-based Al pouch cell via various anodic material, i.e., pure Al, 1050, 3003, 5754 and 6061 Al alloys. The effect of anodic material on the electrochemical property of our batteries were investigated. The electrochemical analysis of five forms anodic materials have characterized by Tafel plot, electrochemical impedance spectroscopy (EIS) and galvanostatic charge/discharge measurements. Result from galvanostatic charge/discharge measurements, the Al battery with 5754 Al alloy shows a higher discharge capacity of 85 mAh/g with natural graphite loading density of ~10 mg/cm2 than other anodic materials

Keywords：Secondary Al battery; Anodic material; Al alloy.

Acknowledgment: The authors highly appreciate the Bureau of Energy (BOE), Ministry of Economy Affair (MOEA), Taiwan for the financial support.
Bifunctional Redox Active Materials for Flow Battery Applications
Authors: Mann Shane C. , Mortimer Nicholas J. , Dumitrascu Adina , Scott Jessica D. , Guarr Thomas F.
Published: February 2020

Nonaqueous redox flow batteries (RFBs) may provide a cost-effective and durable means of energy storage for grid applications, but numerous problems remain. For example, the ion exchange membrane that is generally required is expensive, prone to inefficiencies, and adds significant cell resistance. To avoid these problems, the use of redox polymers or redox-active clusters along with a simple separator has been explored. However, these systems often suffer from inaccessible sites and low mobility.

Recently, we reported a promising approach based on covalently linking an electron acceptor moiety A to an electron donor moiety D to form a bifunctional compound D-L-A (where L represents a simple alkyl or aryl linker). Such systems have at least three accessible stable redox states: the “parent” D-L-A state, an oxidized form D+-L-A (catholyte), and a reduced form D-L-A-
(anolyte). Since operation of the RFB would involve formation of the same product D-L-A at both anode and cathode, crossover is only a problem if the electrode reactions are inefficient.

Numerous D-L-A compounds have been prepared using a wide variety of donor and acceptor groups. Many of these bifunctional compounds undergo chemically and electrochemically reversible oxidation and reduction, yielding predicted RFB cell voltages over 2 V. Additionally, multiple examples of the related D-L-A-L-D compounds incorporating 2e- acceptors A have also been synthesized and characterized. Several of these latter materials are of particular interest, and may provide the basis for RFBs with 2e- operation at 2.4-2.7 V and excellent stability.

The electrochemical properties of several representative D-L-A and D-L-A-L-D systems will be described, and recent progress in the development of nonaqueous RFBs employing covalently linked anolyte-catholyte compounds as active materials will be presented.
Iron Air Batteries: Design Construction and Characterisation
Authors: Figueredo Rodriguez Horacio Antonio , McKerracher Rachel , Alegre Cinthia , Ponce de León Carlos
Published: February 2020

In recent years a renewed interest in developing metal air batteries has arisen, driven by the advances in nanomaterials research that could bring metal air batteries closer to their theoretical specific energy density. For the particular case of the iron-air battery a theoretical energy density of 764 W h kg-1 in combination with the abundance, low cost, eco-friendliness, recyclability, non-toxicity of the materials, and the possibility to work as a secondary battery makes this electrochemical system appealing to develop [1].

Nevertheless, there are several challenges that requires to be improved such as the development of a high efficient iron electrode formulation that reduces the amount of parasitic hydrogen evolution during charge, with a highly porous structure; the development of a good performing bifunctional gas diffusion electrode [2] and the design of a lightweight battery cell design that reduces ohmic losses, electrolyte leaks, allow sufficient air supply to the gas diffusion electrodes and allows evolved gas to be vented [3].

More particular challenges related to the performance of the iron electrodes includes the passivation of the iron electrode at high discharge rates and the low faradaic efficiency due to the parasitic H2 evolution that takes places during the charging process. The engineering of the electrodes in an efficient way to avoid adding extra weight and a way to efficiently supply air are challenging engineering design aspects that have to be addressed to achieve a new level of development.

In this work, the individual iron and air electrodes performance in half-cell configurations will be presented (Fig1) together with a comparison between various iron electrode formulations and some considerations about the engineering design of an iron air battery using additive manufacturing.

References

R. D. McKerracher, C. Ponce de Leon, R. G. A. Wills, A. A. Shah, and F. C. Walsh, “A Review of the Iron–Air Secondary Battery for Energy Storage,” Chempluschem, vol. 80, no. 2, pp. 323–335, 2015.

R. D. McKerracher, H. A. Figueredo-Rodríguez, C. Ponce de León, C. Alegre, V. Baglio, A. S. Aricò, and F. C. Walsh, “A high-performance, bifunctional oxygen electrode catalysed with palladium and nickel-iron hexacyanoferrate,” Electrochim. Acta, vol. 206, pp. 127–133, Jul. 2016.

H. A. Figueredo-Rodríguez, R. D. McKerracher, C. Ponce de León, and F. C. Walsh, “Current distribution in a rectangular flow channel manufactured by 3-D printing,” AIChE J., Aug. 2016.

Figure 1
Correlations between Electrochemical Performance of Aluminum Battery and Graphite Characteristics of Carbon Cathode
Authors: Chiu Sheng-Cheng , Li Yen-Liang , Pan Ping-I , Chiang Chien-Chih , Yang Chang-Chung
Published: February 2020

Rechargeable aluminum battery is promising to replace lead-acid battery for energy storage systems (ESSs) and vehicle cranking system because of non-flammability, ultra-fast charge and discharge capability, environmental-friendliness, and long cycle life. However, Al battery is hindered by low working voltage, low specific capacity of cathode materials, high cost of ionic liquids (ILs) and high self-discharge rate. The first two obstacles are highly related to cathode materials. In this study, electrochemical properties (e.g., cyclic voltammetry and galvanostatic charge/discharge) of Al battery using natural graphite, artificial graphite, soft carbon and hard carbon as cathode materials are investigated. At a current 100 mA/g, natural graphite (loading density of 13 ± 2 mg/cm2) shows the highest discharge capacity of 98 mAh/g. Raman spectroscopy and X-ray diffraction (XRD) are also employed to explore carbon properties, causing different energy storage performance. We suggest carbon, natural graphite, with low-disorder graphite structure delivers high capacity.