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Magnesium bipolar plates (BPPs) offer great advantage in realizing the ultra-lightweight target of proton exchange membrane fuel cells (PEMFCs). However, high corrosion tendency limits its application. To improve the corrosion resistance and surface conductivity of the Mg BPPs, a novel Graphite paper/Cu coating is proposed in this study. 24 h potentiostatic polarization results reveal that the corrosion current density of the coated specimen dropped by 4 orders of magnitude than that of bare Mg. In addition, the interfacial contact resistance (ICR) of Mg BPPs at 1.4 MPa was remarkably reduced after coating, from 597.22 mΩ cm2 to 5.49 mΩ cm2 after the polarization test, respectively, which reached the target set by the U.S. Department of Energy (DOE). The results illustrate that the Graphite paper/Cu coating exhibits excellent anti-corrosion and electrical property, which may offer a promising strategy for the coating design on Mg BPPs for ultra-lightweight PEMFCs.

A high-performance paper electrode is fabricated through coating polypyrrole (PPy) on ordinary laboratory filter paper via a traditional interfacial polymerization method with perchloric acid (HClO4) as a dopant. Owing to the superior mechanical flexibility and environmental stability of the free standing PPy paper, the robust electrode displays an ultrahigh capacitance of 1650 mF cm−2 and remarkable cyclic stability of losing 11.66% after cycling for 10000 times in a three-electrode system. More importantly, the areal specific capacitance has only decreased by 0.08% after five months. Furthermore, by employing the synthesized PPy papers as electrodes and the PVA-H2SO4 gel as electrolyte, the assembled all-solid-state supercapacitor with an areal specific capacitance of 566.5 mF cm−2 is achieved, corresponding to an areal energy density of 38.55 μW h cm−2 and power density of 0.17 mW cm−2. These results suggest that the simple synthesis of PPy paper electrode pave a promising way to exploit flexible and durable energy storage applications.

This study aims at an electrochemical paper-based device for the selective and sensitive detection of exosomes as an economic and flexible platform. Using a laser cutter, a three-electrode platform was patterned on a hydrophobic paper, and then synthetic carbon and silver ink were screen-printed on the paper. Anti-human CD9 antibody was covalently attached to the surface of a carbon ink electrode enriched with graphene oxide aerogel/CoFe2O4@chitosan nanocomposite. The immobilization, incubation and binding time of the capture antibody were investigated as effective parameters. Under optimum conditions, the differential pulse voltammetry (DPV) was used to establish a calibration plot that covered 500 to 5 × 106 exosoms μl−1 with a detection limit of 100 exosome μl−1. This method was implemented successfully for the detection of exosomes in a serum sample. As the results show, the fabricated biosensor is capable of detecting exosomes for the early diagnosis of cancers.

The construction of conductive graphite channels on paper using the pencil drawing method for supercapacitors and sensors has been reported, but its performance needs to be improved to meet practical applications. In this, we develop green and efficient method to prepare high-performance supercapacitor electrodes. After pencil drawing, the polypyrrole graphite active material (PPy-G) is prepared via interfacial polymerization. The graphite layer not only provides an efficient electron transport path but also greatly increases the electrical capacity of electrodes with a good combination of PPy. The prepared electrodes exhibit an excellent area specific capacitance (1654 mF cm−2) and good cycling stability (at 95.3% after 10,000 cycles). Furthermore, the symmetric supercapacitor is prepared using the dual electrodes exhibit a good energy density of 159.6 μWh cm−2 at a power density of 0.8 mW cm−2. The kinetic processes for the electrodes are also further investigated.

This research explores the use of interdigitated electrode arrays (IDE) screen-printed on paper substrate for electrochemical measurements in steady state. Since the steady state is strongly related to IDE dimensions, the accuracy and reproducibility of the fabrication process were assessed for stencils of 120- and 200-mesh. Simulations were used to predict the limiting current and time response, and as a benchmark for comparison with the experimental results. For accurate an comparison, evaporation was prevented by using a homemade humidity box, which enabled measurements for periods as long as 30 min. Although cyclic voltammetry measurements in steady state were possible, this required at least 15 min per cycle when using the smallest electrodes (band width of 0.205 mm). Chronoamperometric measurements reaching steady state were also possible, requiring nearly 5 min for the largest electrodes (band width of 0.376 mm). Regarding the reproducibility of measurements, the relative standard deviations (RSD) of current and response time were near 12% and 26%, respectively. We attribute this mainly to the reproducibility of IDE fabrication (8% RSD). Experimental currents were approximately 30% to 34% of their simulated counterparts. Conversely, the simulated response times were about 30% to 50% of their experimental counterparts. We ascribe these discrepancies to the porosity of the paper (Whatman 2 CHR), estimated to be near 31% under wet conditions. This suggests that fibers inside the paper substrate block the passage of electrochemical species, thereby delaying their diffusion and decreasing the current.

This work deals with the development of a paper based fuel cell for application in micro-nano systems. In this cell, a porous paper serves as a transport medium and eliminates the need for any metering devices that are integral to conventional fuel cells. Since only very small flow rates of reagents can be achieved on paper, these cells produce only a few milli-watts of power. In this work, formic acid is used as the fuel and potassium permanganate is used as the oxidant. Since the cell presented here is membraneless, both formic acid and potassium permanganate are mixed with sulfuric acid, and they form the anolyte and the catholyte, respectively. A special cell geometry has been designed and implemented to minimize and delay the fuel and oxidant cross over effects. In order to keep the cost low, graphite sheets without any metal loading are used as the current collectors. Two variants of filter paper are used for implementing the fuel cells. Cell characterization is accomplished by performing detailed potentiometric and impedance studies. Our study on formic acid cell shows that the porous paper cell architecture can be extended to other fuel-oxidant combinations as well.

We report here a high specific surface area activated carbon loaded with hemin (H-PAC) was synthesized by one-step in situ pyrolysis of paper. As the carrier of hemin, paper-derived activated carbon(PAC) showed high specific surface area (3157 m2 g−1) after optimization. The surface concentration of hemin in the material was effectively increased. Particularly, PAC had a unique interconnected porous structure, which can be used as a continuous conductive framework and provide more active sites. Hemin maintained peroxidase-like activity and showed superior synergistic effect with PAC via pyrolysis, displaying rapid redox characteristics. Under the optimized condition, the composite exhibits high electro–catalytic activities for H2O2 reduction with a low detection limit of 0.087 μM, and high selectivity.

Carbon nanofoam papers (CNFPs) serve as device-ready negative electrodes for nonaqueous sodium-ion (Na-ion) batteries, with fast and reversible Na+ storage at the aerogel-like, disordered carbon nanofoam. These binder-free, scalable electrode architectures are not only advantageous for the construction of practical, high-performance Na-ion cells, but are also effective platforms to analyze charge-storage mechanisms. We use in situ optical imaging at the outer surfaces of CNFPs in a Na half-cell to track the distinctive color changes that accompany the multi-stage Na+-storage processes on scanning these electrodes through their active voltage window (0–2 V vs Na∣Na+). We observe that electrochromic transitions ― black in the native (unsodiated) state→blue→red/gold ― occur primarily with deep levels of sodiation at +. In situ Raman scattering measurements in the same optical cell show that these color changes correlate with shifts in the characteristic G-band Raman peak that would indicate bulk Na+ insertion into nanoscopic graphitic domains within the aerogel-like carbon. The CNFPs also exhibit appreciable Na-ion storage at higher voltage (0.5–2 V vs Na∣Na+), which can be ascribed to surface-based mechanisms that are accompanied by shifts in the D-band Raman peak, but which do not induce appreciable color change.

A flexible conductive graphene paper electrode was prepared by a flow directed filtration of graphene oxide dispersion followed by a gentle thermal reduction treatment of the filtrate. The prepared partially reduced graphene oxide paper (GOPpr) showed a dense packing of graphene sheets with a distinct interlayer distance of 4.35 Å. Its electrode quality for energy storage applications was tested by an electrochemical characterization in the aprotic electrolyte 1M TEABF4 in acetonitrile (AN) which is commonly used for supercapacitors. Within either the first positive or negative charging sweep GOPpr features an electrochemical activation. As a result the graphene framework of the GOPpr becomes accessible for ion insertion and release. The achieved specific capacitance in galvanostatic discharge measurements reached up to 199 Fg-1 at 0.1 Ag-1 for a positively activated and polarized electrode. Even at high specific currents of 10 Ag-1 this value didn't drop below 145 Fg-1. An even higher specific capacitance was determined from cyclic voltammetry where the positively activated electrode yielded up to 270 Fg-1 during the discharge sweep. It's flexible nature the simple processability and the outstanding rate handling capability makes GOPpr an excellent candidate for a positive electrode in bendable supercapacitors and lithium capacitors.

In this article, the optimum printing parameters were found when using silver nanoparticle ink to print on Kodak 4-Star photo paper substrate. Fujifilm Dimatix 2831 was used as the inkjet printer.The printing parameters of interest included the number of printing layers, the drop spacing, and curing temperature of the ink. Analysis of Variance (ANOVA) analysis of the experimental data reveals sintering temperature to be significant (p < 0.05) to improve the conductivity. Pattern conductivity and surface roughness were used to identify the optimum printing parameters. The optimum printing parameters were found to be 15 µm drop spacing, two printing layer, and a sintering temperature of 90°C. The best conductivity measured under the above mentioned condition was found to be 5.56 x 106 Ω-1m-1. Further, the bending test indicated that the printed patterns were unaffected (in terms of conductivity) when flexed around a cylindrical support indicating excellent stability under stress. This study paves the way for developing mechanically robust flexible devices with excellent electrical properties for Internet of Things (IoT) applications.

Electrochemically deposited polymeric film of polyaniline (PANI) is used as a substrate for electrochemical deposition of platinum by using cyclic voltammetry. The electrochemical properties of multi-layered films were analyzed by cyclic voltammetry and AC impedance spectroscopy. The structural properties of multi-layered polymer films were analyzed by SEM, TEM, XRD, XPS, Raman and FTIR. The modified electrode showed strong electrocatalytic activity toward oxidation of toluene in presence of NaNO2/H2SO4 in actetonitrile medium. Toluene gave a sensitive anodic peak at 1.318 V (vs. SCE). Cyclic voltammetry studies suggest that the electrochemical activity of Pt-PANI/CFP electrode is higher than that of Pt/CFP electrode toward toluene oxidation.

In this study, indium modified carbon paper electrode is investigated as the positive electrode for all-vanadium redox flow battery (VRFB). The electrochemical performance is studied using cyclic voltammetry, electrochemical impedance spectroscopy and stability test toward V (IV)/V (V) redox reaction. The results show that the modified carbon paper exhibits excellent electrocatalytic activity and stability after repetitive 100-cycle test in an electrolyte containing 0.5 M VOSO4, while degradation is observed in pristine carbon paper. Such improvement is due to the indium particles deposited on the carbon fibers acting as stable active sites promoting the vanadium redox reactions and reducing charge transfer resistance as indicated by impedance measurement. Full cell performance is assessed via polarization curve analysis at different states of charge. A simple cell set-up (without flow field) employing the modified electrode exhibited limiting current of 125 mA cm2, which is 73% higher than the cell employing pristine carbon paper (72 mA cm2) at SOC of 96%. Overall, the results demonstrate that indium deposition on carbon paper promotes the electrochemical performance and provides an opportunity for further investigation in the exploration of metal modification of carbon materials for VRFB.

Voltammetric determination of morin on carbon fiber paper (CFP) electrode modified by electropolymerization of 2,5-dimercapto1,3,4- thiadiazole (DMTD) in phosphate buffer solution (PB, pH 9.0) have been studied. This modified electrode showed strong electrocatalytic activity toward the oxidation of morin, a flavonoid at physiological pH (PB, pH 7.0). Morin gave a sensitive anodic peak at 0.245 V (vs. SCE). The parameters influencing the anodic peak of morin such as effect of pH, effect of scan rate and concentration have been optimized. The electrochemical process was found to be irreversible and adsorption-controlled. Under the optimum conditions, the anodic peak current was linear to concentration of morin in the range of 2.5 x 10(-10)-2.75 x 10(-9) M and detection limit was found to be 8.3 x 10(-11) M. The practical application of the modified electrode was successfully demonstrated for the determination of morin in mulberry leaves. (C) 2016 The Electrochemical Society. All rights reserved.

This paper describes the design and testing of a microfluidic biofuel cell that uses a flow-through bioanode and an air-breathing cathode. The bioanode is Toray carbon paper with glucose dehydrogenase (GDH), multi-walled carbon nanotubes (MWCNTs), and methylene green immobilized within a hydrogel. The cathode consists of a commercially available air-breathing platinum cathode hot pressed to a Nafion membrane. All remaining biofuel cell components were laser-cut from poly(methyl methacrylate) (PMMA) and silicone sheets. Half-cell experiments indicate that cathode variability limits the biofuel cell. An examination of flow rate effects on the biofuel cell showed that the current density increased sharply up to about 1 mL/min. Tested at this flow rate, the flow-through biofuel cell achieved a maximum current and power density of 705 μA/cm 2 and 146 μW/cm 2 . This was a 6% and 29% improvement in the current and power density, respectively, compared to the previously demonstrated bioanode without flow. Fuel utilization was calculated based on the measured current and by measuring UV-Vis absorbance of the reduced form of hydroxybenzhydrazide. The maximum fuel utilization was 5.8% at a flow rate of 0.05 mL/min. Finally, a numerical model of the biofuel cell was designed and its results compare favorably to actual data.

In this work, a flexible and freestanding Carbon Nanofiber/Cobalt hydroxide (CNF/Co(OH) 2 ) composite paper is prepared via electrospinning followed by a simple chemical precipitation method. The structure characterizations show that Co(OH) 2 particles are well dispersed on the surface of the CNF, forming a thin and flexible composite paper. Due to the reinforcing effects coming from the double layer capacitance of CNF and the pseudo-capacitance of Co(OH) 2 , the supercapacitive performance of pure CNF and pure Co(OH) 2 are mutually improved significantly after combination. The CNF/Co(OH) 2 paper exhibits the largest specific capacitance in the potential range of −1–0 V, about 24% higher than that of pure CNF paper; while the specific capacitance of the Co(OH) 2 can increase by 30% in the potential range of −0.2−0.35 V after precipitated on the CNF. Our work probably gives a new insight for designing and synthesizing electrode materials of supercapacitor and other energy-storage devices.

This research introduces the design of a gas-diffusional cathode employing bilirubin oxidase (BOx) immobilized on a complex matrix composed of carbon nanotube (CNT) modified Toray paper (TP) and, encapsulated in silica-gel. The developed enzymatic cathode consists of two layers. One is the hydrophobic gas-diffusional layer (GDL) and the other a hydrophilic catalytic layer (CL) which were combined by pressing at 1000 psi for five minutes. The GDL (35% weight teflonized Vulcan carbon powder (XC35)) that is exposed to air has hydrophobic and porous properties that facilitate oxygen diffusion. The CL consists of a thin, high surface area, 3D CNT/silica-gel matrix where the 3D-enzymatic structure is immobilized and preserved. The nanostructured architecture of the CL was designed to improve conductivity and surface area. Such a design was achieved by modifying the TP surface with CNTs. CNTs are grown on TP by chemical vapor deposition which is possible by electrodepositing Ni seeds via pulse chronoamperometry. Entrapment of BOx was achieved by using tetramethyl orthosilicate (TMOS), a highly volatile compound that results in a polymeric condensation reaction with H2O at room temperature. TMOS polymerization of the cathode surface was performed in a chemical vapor deposition process to form a silica-gel matrix. The gas diffusional cathode was assembled to a capillary driven microfluidic system to be electrochemically characterized. The characterization was performed from electrolyte pH 5 to pH 8 with increments 0.5 in pH. The best performance was observed at pH 5.5 showing a current output of 655.07 ± 146.18 μA.cm −2 and 345.36 ± 30.04 μA.cm −2 at 0 V and 0.3 V, respectively. At a pH of 7.5 the current generated was 287.05 ± 20.37 μA.cm −2 and 205.37 ± 1.57 μA.cm −2 at 0 V and 0.3 V, respectively. The results show the stability of the enzymatic structure, subject to various pH, is maintained within the 3D-CNT silica-gel matrix for pH lower than 8. Future work will focus on storage life and stability over time. © The Author(s) 2014. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any

In this article, a room temperature ammonia sensor on a paper substrate is reported. The electrochemical sensor is constructed using platinum electrodes and ionic liquid electrolyte. The amperometric staircase response shows discernible signal differentiation between each concentration of NH3 (5-25ppm). The rise time and fall time for the NH­3 sensor were found to be 8 s and 7s respectively. The authors believe such a fast responding NH3 sensor on a paper substrate has never been reported. The detection limit was deduced to be 1 ppm based on the sensitivity versus concentration plot. A 17% decrease in sensor response was observed over 30 days of testing. Implementing an antenna on the paper substrate co-located with the sensor for wireless operation is envisioned in future.

Lithiation/delithiation of Cu 6 Sn 5 both electrochemically and mechanochemically prepared on a carbon paper (CP) current collector was investigated by repeated galvanostatic cycles with time-limited charges to insert different amounts of lithium per Sn atom (Li/Sn) into the alloy. The results demonstrated that, unlike Cu 6 Sn 5 electrodeposited on Cu foil, both electrochemical and mechanochemical Cu 6 Sn 5 on CP can undergo hundreds of lithiation/delithiation cycles with Li/Sn > 2 at high current density (0.74 mA cm - 2 ), thereby delivering constant amounts of charge with coulombic efficiency near 100%. The Cu 6 Sn 5 /CP electrodes with a loading of 6.6 mg cm - 2 and charge limited to 2.43 Li/Sn yielded a specific capacity of 330 mAh g - 1 and a capacity per geometric area of 2.18 mAh cm - 2 . These values compare well with those of graphite-based anodes of commercial batteries. The significant improvement in cyclability performance of the Cu 6 Sn 5 /CP electrodes is due to the CP current collector's three-dimensional conductive matrix, which preserves the electric contact over cycling so that alloy cracking becomes less detrimental for the electric contact.

A new approach for measuring lignin content of kraft pulps is described based on the voltammetric measurement of catalytic reactions involving lignin and redox mediators. This electrochemical method consists of measuring the rate of regeneration of a lignin redox catalyst in the presence of pulp following its oxidation at a voltammetric electrode. The intensity of the catalytic current generated at the electrode surface was found to be proportional to the amount of lignin present in a pulp. Within pulp types (softwood, hardwood, or oxygen delignified) linear relationships were obtained between the intensities of the generated current and a range of kappa numbers. The redox characteristics and concentration of the mediator, and the voltage sweep rate of the voltammetric procedure, are among parameters that can be tuned to obtain linear relationships with kappa number of various Pulps.

The renaissance of sodium-ion batteries (SIBs) in the last few years provides a promising environmentally friendly alternative for energy storage and conversion (ESC).1 , 2 MoS2, a layered material with a large interlayer spacing along the c-axis (0.62 nm), has been attracting extraordinary attention as anode materials for SIBs. However, pure MoS2 exhibited poor rate capability and fast capacity decay upon cycling. Nanostructuring and hierarchical electrode architectures are required to facilitate transport of Na-ions within electrodes.3 Herein, we report on a rational design of freestanding anode materials for sodium-ion batteries, consisting of MoS2 nanosheets aligned vertically on carbon paper derived from paper towel.4 The hierarchical structure enables sufficient electrode/electrolyte interaction and fast electron transportation. Meanwhile, the unique architecture can minimize the excessive interface between carbon and electrolyte, enabling high ICE. When employed as freestanding electrodes for SIBs, the as-prepared MoS2@carbon paper composites delivered a high reversible capacity of 446 mA h g-1 at 20 mA g-1, high ICE (79.5%), and promising rate capability. Even at a high current density of 1000 mA g-1, a reversible capacity of 205 mA h g-1 was maintained.By exploiting in situ Raman spectroscopy, we observed the reversibility of the phase transition from 2H-MoS2 to 1T-MoS2 during the sodium-ion intercalation/de-intercalation process. References 1. Xiuqiang Xie, Zhimin Ao, Dawei Su, Jinqiang Zhang and Guoxiu Wang, MoS2/graphene composite anodes with enhanced performance for sodium-ion batteries: the role of the two-dimensional heterointerface, Advanced Functional Materials , 2015, 25, 1393-1403. 2. Xiuqiang Xie, Katja Kretschmer, Jinqiang Zhang, Bing Sun, Dawei Su and Guoxiu Wang, Sn@CNT nanopillars grown perpendicularly on carbon paper: A novel free-standing anode for sodium ion batteries, Nano Energy , 2015, 13, 208-217. 3. Yury Gogotsi, What nano can do for energy storage, ACS Nano , 2014, 8, 5369-5371. 4. Xiuqiang Xie, Taron Makaryan, Mengqiang Zhao, Katherine L. Van Aken, Yury Gogotsi and Guoxiu Wang, MoS2 nanosheets vertically aligned on carbon paper: a freestanding electrode for highly reversible sodium-ion batteries, Advanced Energy Materials , 2015, DOI: 10.1002/aenm.201502161. Figure 1

Many carbon materials have desirable electrochemical, mechanical, electrical, and thermal properties that make them ideal candidates for dual-use energy-storage devices integrated into fiber-matrix composites or textiles. Commercial fabrics are cost-effective, scalable materials that are often fabricated specifically for composite applications. However, the electrochemical properties of these commercial materials are largely unknown. This study focuses on the properties of unmodified commercial carbon fabric materials for use in electrochemical devices such as lithium-ion batteries. Electrochemical capacity was evaluated for carbon fibers derived from a wide variety of grades of fabrics based on polyacrylonitrile (PAN), pitch, or activated carbon, and carbon papers made from carbon nanotubes or nanofoams. Double-layer capacitances were also measured for potential application to supercapacitors. The fiber microstructures were analyzed via X-ray diffraction and Raman spectroscopy. Nanofoam papers demonstrated the best overall electrochemical performance, with capacities consistently achieving 135 mAh/g after 50 cycles and capacitances of 5-7 F/g, but the mechanical properties were poor. IM7 and T300 PAN-based woven fabrics demonstrated the best potential for multifunctional use, with reversible-discharge electrochemical capacities as high as 158 mAh/g after 50 cycles and tensile strengths of 3-5 GPa. Removing the polymer sizing from PAN-based fibers did not appear to improve performance.

A novel lithium ion battery cathode structure was produced which has the potential for excellent capacity retention and good thermal management. In these cathodes, the active cathode material (lithium iron phosphate) was carbon bonded to a thermally and electrically conductive carbon fiber paper (CFP) support. Electrochemical testing was performed on Swagelok cells consisting of CFP cathodes and lithium anodes. High specific energy, near-theoretical capacity, and good cycling performance were demonstrated for 0.11 mm and 0.37 mm thick CFP cathodes.

The low yield of indium tin oxide (ITO) thin-film deposition is an important factor in optoelectronic semiconductor production. An effective reclamation process was developed that uses ultrasonic electroetching and a designed bulge-form tool to remove the defective ITO nanostructure from the optical polyethyleneterephthalate (PET) surfaces of digital paper. In the current experiment, the assistance of ultrasonics was found to be more effective than pulsed current, requiring no increase in electric power. The large length of the bulge-form tool's cathode, with a small gap width between the cathode and the workpiece, requires less time to do the same amount of ITO etching. The small end radius of the cathode, combined with enough electric power, results in very fast etching. Additionally, electric power, when combined with a fast feed rate, provides highly effective etching. A higher rate of removal of the defective ITO nanostructure corresponds to high temperature, a large electrolyte flow rate, or a high rotational speed of the electrodes. Importantly, ultrasonic electroetching with the designed bulge-form tool requires only a short period of time to remove the ITO's thin-film coatings easily and cleanly.

Carbon paper (CP) was modified with a layer of boron-doped nanocrystalline diamond (BND) in order to improve the material's chemical resistance and microstructural stability during exposure to aggressive electrochemical environments. In the procedure, carbon fibers in the CP were coated up to a depth of about 50 μm with a thin layer (ca. 1 μm) of electrically conducting diamond. The diamond layer was deposited by microwave plasma-assisted chemical vapor deposition using an argon-rich CH 4 /H 2 /Ar/B 2 H 6 source gas mixture. X-ray diffraction and Raman spectroscopy confirmed the presence of a crystalline diamond overlayer. The electrodeposition of Pt electrocatalyst particles was used to probe the electrochemical activity of the diamond-coated electrode. The metal phase was formed using pulsed galvanostatic deposition (cathodic) at 1.25 mA/cm 2 (geom.) and evaluated in terms of (i) the particle size and distribution, (ii) the stability during anodic polarization, and (iii) the electrochemical activity for the reduction of dissolved oxygen. Pt particles with a diameter of 100-300 nm and a particle density of 10 8 -10 9 cm -2 were formed on all regions of the BND electrode. Importantly, the diamond-modified electrode exhibited superior morphological and microstructural stability during anodic polarization (1.4 V vs Ag/AgCl) as compared to CP, both in the presence and absence of Pt. The results demonstrate that surface modification with electrically conducting diamond is a means to improve the dimensional stability of sp 2 carbon materials, particularly those used in fuel cells.

Porous papers and felts fabricated from BN and Y/sub 2/O/sub 3/ fibers were evaluated as electrode separators for Li--Al/LiCl--KCl/FeS/sub x/ cells. The physical and mechanical properties were determined, and in-cell tests exceeding 1000 h were conducted. The papers and felts had adequate strength and flexibility for cell assembly and performed well during cell testing. Results from the property measurements are presented, and the performance of these materials in the cell tests is discussed. 7 figures, 2 tables.