Owing to the rapid increase in global energy consumption, which is currently based on fossil fuel combustion, the importance of renewable energy has become increasingly apparent. Solar energy is one of the most promising candidates to replace conventional energy sources, and various types of photovoltaic devices, including dye-sensitized solar cells, are being intensively investigated as a means for the efficient utilization of sunlight. However, the use of Pt in the counter electrodes of dye-sensitized solar cells limits their economic feasibility for practical and industrial applications. In the present study, to develop an active and economical material to replace Pt in dye-sensitized solar cells, we prepare a nanostructured iron carbide/carbon composite by electrochemical anodization of Fe foil followed by heat treatment in carbon-bearing gas atmosphere, which lead to the formation of conformal carbon shell on the surface of crystalline Fe₃C. The superior catalytic properties of the iron carbide/carbon composite in the cobalt bipyridine redox electrolyte to those of Pt are confirmed by various electrochemical characterization methods. When used as the counter electrode in a dye-sensitized solar cell, the superior properties of the composite provide an 8.0% increase in power conversion efficiency compared to that achieved with a Pt counter electrode.

由于当前基于化石燃料燃烧的全球能源消耗的迅速增加，可再生能源的重要性变得越来越明显。太阳能是替代传统能源的最有前途的候选者之一，并且包括染料敏化太阳能电池在内的各种类型的光伏设备都在进行深入研究，以作为有效利用太阳光的一种手段。但是，在染料敏化太阳能电池的对电极中使用Pt限制了其在实际和工业应用中的经济可行性。在本研究中，要开发一种活性和经济的材料来代替染料敏化太阳能电池中的Pt，_3C。通过各种电化学表征方法证实了联吡啶钴氧化还原电解质中碳化铁/碳复合物的催化性能优于Pt。当用作染料敏化太阳能电池中的对电极时，与Pt对电极相比，该复合材料的优越性能可将功率转换效率提高8.0％。