Abstract It's critical and challenging to investigate cost-effective and strong electrocatalyst within the advancement of large scaled dye-sensitized solar cells (DSSCs). In this work, we develop a novel strategy to prepare NiS2 microspheres interface with 2D graphene nanosheets constructed through a facile hydrothermal technique. Na2S2O3.5H2O plays an important role as the reducing agent for GO as well as the sulfur source for NiS2. The microstructures, morphologies and optical properties of the NiS2/graphene hybrid composite samples were investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and N2 adsorption–desorption isotherm, UV-Vis diffuse reflectance spectra and photoluminescence spectra analysis. A significant narrowing the band gap (2.69 eV-2.44 eV) and control the prevention of electron-hole pair recombination process was examined through UV and PL studies. The J-V characteristics of the fabricated sandwich type DSSC device was monitored and the results demonstrate that NiS2/graphene hybrid photoanode displayed an excellent electrocatalytic activity in the reduction of I3− showing a power conversion efficiency of 12.56%, which is 2.5 times better than bare NiS2 photoanode (5.02%). This is ascribed to the low resistance to diffusion and transfer of electrolyte ions. These results suggest that the NiS2/graphene prepared through a facile process is a promising substitute to Pt electrode.

中文翻译：

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用于高效染料敏化太阳能电池的多孔 NiS2/石墨烯异质结光阳极的低成本和新型制备

摘要 在大规模染料敏化太阳能电池 (DSSC) 的发展过程中，研究具有成本效益和强效的电催化剂至关重要且具有挑战性。在这项工作中，我们开发了一种新的策略来制备 NiS2 微球与通过简单的水热技术构建的二维石墨烯纳米片的界面。Na2S2O3.5H2O 作为 GO 的还原剂和 NiS2 的硫源起着重要的作用。通过X射线衍射、扫描电子显微镜、透射电子显微镜和N2吸附-解吸等温线、UV-Vis漫反射光谱和光致发光光谱分析研究了NiS2/石墨烯杂化复合材料样品的微观结构、形貌和光学性能。显着缩小带隙 (2.69 eV-2. 44 eV) 和控制防止电子-空穴对复合过程通过 UV 和 PL 研究进行了检查。监测制造的夹心型 DSSC 器件的 JV 特性，结果表明 NiS2/石墨烯混合光阳极在还原 I3− 方面表现出优异的电催化活性，功率转换效率为 12.56%，比裸 NiS2 好 2.5 倍光阳极 (5.02%)。这归因于对电解质离子的扩散和转移的低阻力。这些结果表明，通过简单的工艺制备的 NiS2/石墨烯是 Pt 电极的有前途的替代品。监测制造的夹心型 DSSC 器件的 JV 特性，结果表明 NiS2/石墨烯混合光阳极在还原 I3− 方面表现出优异的电催化活性，功率转换效率为 12.56%，比裸 NiS2 好 2.5 倍光阳极 (5.02%)。这归因于对电解质离子的扩散和转移的低阻力。这些结果表明，通过简单的工艺制备的 NiS2/石墨烯是 Pt 电极的有前途的替代品。监测制造的夹心型 DSSC 器件的 JV 特性，结果表明 NiS2/石墨烯混合光阳极在还原 I3− 方面表现出优异的电催化活性，功率转换效率为 12.56%，比裸 NiS2 好 2.5 倍光阳极 (5.02%)。这归因于对电解质离子的扩散和转移的低阻力。这些结果表明，通过简单的工艺制备的 NiS2/石墨烯是 Pt 电极的有前途的替代品。