Trinary Nanohybrid Nanocomposite (Ag/MoS2/ZnO): A Plausible Photoelectrode for Photoelectrochemical Water Splitting

Current study aims to synthesis trinary nanohybrid composite (Ag/MoS2/ZnO) and evaluate its potential application as photoanode to produce hydrogen gas with low voltage (0.2 V vs. RHE). Combination of structural analysis via microscopy analysis and elemental spectroscopy has proven the successful in integrating Ag/MoS2 dispersion phase onto ZnO nanorods matrix. Optical characterization on the as-prepared Ag/MoS2/ZnO indicates there is an improvement of light absorption towards visible light region, which is benefiting the photoelectrochemical process by creating additional photoexciton. Photoelectrochemical performance analysis reveals that the performance of trinary nanohybrid composites exhibits better water splitting efficiency as compared to its single component counterpart (ZnO). Among all the samples, 20 wt% Ag/MoS2 depicts the best photoelectrochemical performance with the low onset potential (0.3V vs. RHE) and photoconversion efficiency of 1.15% at peak voltage of 0.85 V (vs. RHE). Without any external supplied voltage, chronoamperometry measurement indicate there is a short circuit current of 0.70 mA/cm2 and similar bias-free condition has found to be able in sustaining self-driven hydrogen gas generation up to 54.49 μL according to gas chromatography-analysis. The enhancement of photoelectrochemical performance has been discussed and accredited to the presence of active edges in MoS2 nanoflakes in addition to Ag nanoparticles that facilitate the efficient charge separation process. Current work is envisaged to serve as a platform for exploring the potential in using multi-compounds integration approach for realizing bias-free water splitting application.

本研究旨在合成三组分纳米复合材料（Ag/MoS2/ZnO）并评估其在低电压（0.2 V相对于标准氢电极，RHE）条件下作为光阳极产生氢气的潜力。通过显微镜分析和元素光谱学的结构分析证实，将Ag/MoS2分散相成功集成到ZnO纳米棒基体中。对制备好的Ag/MoS2/ZnO复合材料的光学表征表明，其对可见光区的光吸收能力得到提升，这有利于光电化学过程，通过创造额外的光激发子而受益。光电化学性能分析揭示，与单一组分（ZnO）相比，三组分纳米复合材料的分解水效率更高。在所有样品中，20 wt%的Ag/MoS2展现出最佳的光电化学性能，具有低的开电压（0.3V相对于标准氢电极，RHE）和1.15%的光电转换效率，峰值电压为0.85 V（相对于标准氢电极，RHE）。无需外部施加电压，计时电流法测量表明短路电流为0.70 mA/cm2，并且类似的偏置自由条件被发现能够维持自驱动氢气生成，根据气相色谱分析，达到54.49 μL。光电化学性能的提升归因于MoS2纳米片活性边缘的存在，以及Ag纳米粒子的存在，这些都有助于促进高效的电荷分离过程。当前的研究工作预期将成为探索利用多化合物集成方法实现偏置自由水分解应用的潜在平台的基石。