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Abstract: MoSi2 is introduced into dye-sensitized solar cell (DSC) as counter electrode (CE) catalyst for the first time, and the DSC produces power conversion efficiency (PCE) of 4.87%. To improve the catalytic activity, Pt/MoSi2 composite catalyst is synthesized and it is found that 1.13 wt% of Pt loading is enough for achieving high catalytic activity. After optimization, the DSC using the Pt/MoSi2 composite CE shows high PCE of 7.68%, close to the Pt CE based DSC (7.94%). [Copyright &y& Elsevier]

A composite electrode of poly(3,4‐ethylenedioxythiophene) (PEDOT)@4A‐molecular sieve is synthesized by a simple electrochemical polymerization method for supercapacitor applications. The prepared PEDOT@4A‐molecular sieve composite exhibits excellent capacitive behavior, with high reversibility in the electrochemical window from −0.8 V and 0.2 V. The specific capacitance of the PEDOT@4A‐molecular sieve composite electrode reaches 163.4 F g−1 at 0.25 A g−1, that is much higher than those of the pristine 4A‐molecular sieve (14.8 F g−1) and PEDOT (117.0 F g−1) electrodes at the same conditions. The composite electrode also presents excellent cycle stability, and the specific capacitance retains 82.8% of its initial value after continuous 1000 charge‐discharge cycles. This work indicates that synthesis of a composite electrode is a promising approach for enhancing the electrochemical properties of the supercapacitor electrode due to the synergistic effect. [ABSTRACT FROM AUTHOR]

Abstract: Binary composite of Pt decorated transition metal compounds (WO2, TiC, and VN) were introduced into dye-sensitized solar cells and excellent performance were obtained, almost 20% better than unitary materials. Ternary composite of Pt/WO2/TiO2 was also prepared to further improve the photovoltaic performance. [Copyright &y& Elsevier]

Abstract Carbon molecular sieve is introduced as flexible supercapacitor electrode for the first time. The carbon molecular sieve electrode generates a specific capacitance of 108.0 F·g−1 and demonstrates an excellent stability with 98.5% preservation of its initial capacitance after 10,000 charging-discharging cycles. To further enhance the electrochemical performance, a flexible 3-D structured composite electrode is synthesized via an electrochemical polymerization method by depositing poly 3,4‑ethylenedioxythiophene film on the carbon molecular sieve surface, denoted as carbon molecular sieve@poly 3,4‑ethylenedioxythiophene. The specific capacitance of the composite electrode is up to 126.0 F·g−1, higher than both poly 3,4‑ethylenedioxythiophene (115.7 F·g−1) and carbon molecular sieve (108.0 F·g−1). Moreover, the flexible composite electrode preserves 96.0% of its initial capacitance after 10,000 charging-discharging cycles at 1.00 A·g−1. The superior performance of the composite electrode is attributed to the combined merits of the superior conductivity and excellent cycle stability of the carbon molecular sieve and 3-D porous network configuration of the poly 3,4‑ethylenedioxythiophene. [ABSTRACT FROM AUTHOR]

A composite (Pt/CS) catalyst produced by homogeneously depositing Pt nanoparticles on a carbon spheres (CS) surface is synthesized by a simple method. A large-scale, highly effective, and flexible counter electrode is further fabricated with this composite catalyst on an ITO-PEN substrate for dye-sensitized solar cells (DSCs). As inferred from cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel polarization curves results, this flexible Pt/CS counter electrode exhibits higher catalytic activity toward Co 3+/2+ redox couple regeneration than Pt and CS counter electrodes. The supercatalytic behavior of Pt/CS can essentially be attributed to the low apparent activation energy ( E a ) of the redox reaction between Co 3+ and Co 2+ . Using the Pt/CS counter electrode, a high power conversion efficiency (PCE) of 9.02% is achieved with a small DSCs (16 mm 2 ), and the largescale device (360 mm 2 ) generates a PCE of 6.26% under 100 mW cm −2 of simulated sunlight illumination. [ABSTRACT FROM AUTHOR]

In this work, a feasible method is put forward to synthesize carbon supported transition metal carbide composites (Cr 3 C 2 -C, Mo 2 C-C, WC-C, VC-C, NbC-C, TaC-C, and TiC-C, et al.) by utilizing metal chlorides as metal sources, and phenolic resin as carbon source. As demonstrated by the cyclic voltammetry results, the carbon supported carbide composites present higher peak current densities as well as lower peak-to-peak separations. Moreover, the electrochemical impedance spectroscopy results indicate lower charge transfer resistance over the pristine carbides. Compared with the carbides, the carbon supported carbide composites show much higher catalytic activities towards the cobalt redox couple regeneration in dye-sensitized solar cells (DSCs) as counter electrode. In the DSCs system, the devices using the TiC-C, VC-C, and WC-C composite counter electrodes display power conversion efficiencies of 8.85%. 9.75% and 9.42%, respectively, which are much higher than those of the counterparts utilizing TiC, VC and WC counter electrodes. [ABSTRACT FROM AUTHOR]

The composite of cobaltosic sulfide/electrospun carbon nanofibers (Co 3 S 4 /ECs) with high catalytic activity have been successfully synthesized by combining the versatility of the electrospunning technique and following a hydrothermal synthesis method. And the composite of Co 3 S 4 /ECs was introduced into dye-sensitized solar cells (DSCs) as counter electrode (CE) for the first time. Combining a new electrolyte with iodide free redox couples involving Co 3+/2+ , the Co 3 S 4 /ECs composite demonstrated good performance in DSCs. Under AM 1.5G illuminations, the DSCs based on Co 3 S 4 /ECs composite CE achieved a high power conversion efficiency (PCE) of 9.23%, which increased by 10.1% compared to the DSCs based on Pt CE (8.38%). [ABSTRACT FROM AUTHOR]

To improve the catalytic activity of Nb 2 O 5 , a composite Nb 2 O 5 /C (Nb 2 O 5 imbedded in carbon support) is synthesized with a simple in situ method and then introduced the composite into dye-sensitized solar cells (DSCs) as a counter electrode (CE) catalyst. Based on the analysis of the cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel-polarization curve measurements, the catalytic activity of the Nb 2 O 5 /C composite for the regeneration of iodide-free redox couples of polysulfide (T 2 /T − ) and cobalt complex (Co 3+/2+ ) is indeed enhanced significantly as compared with pure Nb 2 O 5 , because the composite electrode eliminates the particle aggregation and forms a mesoporous network structure with large pore size. The T 2 /T − electrolyte based DSCs with Nb 2 O 5 /C CE yields a high power conversion efficiency (PCE) of 6.11%, generating a great improvement of 63.8% as compared to the Pt CE based DSCs. In addition, the Nb 2 O 5 /C exhibits higher catalytic activity than Pt for regenerating the Co 3+/2+ redox couple and the DSCs using Nb 2 O 5 /C CE shows a high PCE of 9.86%. [ABSTRACT FROM AUTHOR]