Lee Lawrence Tien Lin, He Jian, Wang Baohua, Ma Yaping, Wong King Young, Li Quan, Xiao Xudong, Chen Tao
Department of Physics, The Chinese University of Hong Kong, Shatin N. T., Hong Kong, P. R. China.
Sci Rep. 2014 Feb 14;4:4063. doi: 10.1038/srep04063.
Due to the two-dimensional confinement of electrons, single- and few-layer MoSe₂ nanostructures exhibit unusual optical and electrical properties and have found wide applications in catalytic hydrogen evolution reaction, field effect transistor, electrochemical intercalation, and so on. Here we present a new application in dye-sensitized solar cell as catalyst for the reduction of I₃(-) to I(-) at the counter electrode. The few-layer MoSe₂ is fabricated by surface selenization of Mo-coated soda-lime glass. Our results show that the few-layer MoSe₂ displays high catalytic efficiency for the regeneration of I(-) species, which in turn yields a photovoltaic energy conversion efficiency of 9.00%, while the identical photoanode coupling with "champion" electrode based on Pt nanoparticles on FTO glass generates efficiency only 8.68%. Thus, a Pt- and FTO-free counter electrode outperforming the best conventional combination is obtained. In this electrode, Mo film is found to significantly decrease the sheet resistance of the counter electrode, contributing to the excellent device performance. Since all of the elements in the electrode are of high abundance ratios, this type of electrode is promising for the fabrication of large area devices at low materials cost.
由于电子的二维限制，单层和少层MoSe₂纳米结构表现出异常的光学和电学性质，并在催化析氢反应、场效应晶体管、电化学插层等方面得到了广泛应用。在此，我们展示了其在染料敏化太阳能电池中的一种新应用，即作为对电极上将I₃⁻还原为I⁻的催化剂。少层MoSe₂是通过在涂有Mo的钠钙玻璃表面进行硒化制备的。我们的结果表明，少层MoSe₂对I⁻物种的再生显示出高催化效率，这反过来产生了9.00%的光电能量转换效率，而与基于FTO玻璃上的Pt纳米颗粒的“冠军”电极耦合的相同光阳极产生的效率仅为8.68%。因此，获得了一种优于最佳传统组合的无Pt和无FTO的对电极。在这种电极中，发现Mo膜显著降低了对电极的薄层电阻，有助于实现优异的器件性能。由于电极中的所有元素都具有高丰度比，这种类型的电极有望以低成本材料制造大面积器件。
