Cheng Chao-Kuang, Lin Che-Hsien, Wu Hsuan-Chung, Ma Chen-Chi M, Yeh Tsung-Kuang, Chou Huei-Yu, Tsai Chuen-Horng, Hsieh Chien-Kuo
Department of Engineering and System Science, National Tsing Hua University, Hsinchu, 30013, Taiwan, Republic of China.
Department of Materials Engineering, Ming Chi University of Technology, New Taipei City, 24301, Taiwan, Republic of China.
Nanoscale Res Lett. 2016 Dec;11(1):117. doi: 10.1186/s11671-016-1277-0. Epub 2016 Feb 29.
In this study, we reported the synthesis of the two-dimensional (2D) nanocomposite of molybdenum disulfide and nitrogen-doped graphene oxide (MoS2/nGO) as a platinum-free counter electrode (CE) for dye-sensitized solar cells (DSSCs). X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy were used to examine the characteristics of the 2D nanocomposite of MoS2/nGO. The cyclic voltammetry (CV), electrochemical impedance spectra (EIS), and the Tafel polarization measurements were carried out to examine the electrocatalytic abilities. XPS and Raman results showed the 2D behaviors of the prepared nanomaterials. HRTEM micrographs showed the direct evidence of the 2D nanocomposite of MoS2/nGO. The results of electrocatalytic examinations indicated the MoS2/nGO owning the low charge transfer resistance, high electrocatalytic activity, and fast reaction kinetics for the reduction of triiodide to iodide on the electrolyte-electrode interface. The 2D nanocomposite of MoS2/nGO combined the advantages of the high specific surface of nGO and the plenty edge sites of MoS2 and showed the promoted properties different from those of their individual constituents to create a new outstanding property. The DSSC with MoS2/nGO nanocomposite CE showed a photovoltaic conversion efficiency (PCE) of 5.95 % under an illumination of AM 1.5 (100 mW/cm(2)), which was up to 92.2 % of the DSSC with the conventional platinum (Pt) CE (PCE = 6.43 %). These results reveal the potential of the MoS2/nGO nanocomposite in the use of low-cost, scalable, and efficient Pt-free CEs for DSSCs.
在本研究中，我们报道了二硫化钼与氮掺杂氧化石墨烯（MoS2/nGO）的二维（2D）纳米复合材料的合成，该材料用作染料敏化太阳能电池（DSSC）的无铂对电极（CE）。采用X射线光电子能谱（XPS）、高分辨率透射电子显微镜（HRTEM）和拉曼光谱对MoS2/nGO二维纳米复合材料的特性进行了研究。通过循环伏安法（CV）、电化学阻抗谱（EIS）和塔菲尔极化测量来考察其电催化能力。XPS和拉曼结果显示了所制备纳米材料的二维特性。HRTEM显微照片显示了MoS2/nGO二维纳米复合材料的直接证据。电催化测试结果表明，MoS2/nGO在电解质 - 电极界面上对三碘化物还原为碘化物具有低电荷转移电阻、高电催化活性和快速反应动力学。MoS2/nGO二维纳米复合材料结合了nGO高比表面积和MoS2大量边缘位点的优点，表现出与其单个组分不同的增强性能，从而产生了一种新的优异性能。具有MoS2/nGO纳米复合材料CE的DSSC在AM 1.5（100 mW/cm²）光照下的光电转换效率（PCE）为5.95%，高达具有传统铂（Pt）CE的DSSC（PCE = 6.43%）的92.2%。这些结果揭示了MoS2/nGO纳米复合材料在用于DSSC的低成本、可扩展且高效的无铂CE方面的潜力。
