材料期刊网

将太阳能转化成氢能来发展氢能源经济是人类社会可持续发展的必由之路.光电化学分解水制氢是太阳能-氢能转换中具有重要应用前景的技术.经过近50年的发展,光电化学分解水制氢技术遇到了瓶颈,主要是缺乏高效稳定的光电极.近年来,通过沉积TiOx保护层的策略,部分光电极的稳定性得到了显著提升,因此,提高光电极的太阳能-氢能转换效率成为一项愈加重要的任务.其中,改善光电极载流子传输能够有效地提高太阳能-氢能转换效率.着重讨论了几种改善光电极中载流子传输的策略:制备有利于载流子扩散和迁移的纳米结构;通过掺杂提高材料的导电性;通过制备工艺的优化减少阻碍载流子传输的缺陷;构建半导体结;使用与材料多子输运匹配的导电衬底或引入少子阻隔层等.

The sustainable development of society will depend on the hydrogen economic which is based on the conversion of solar energy. Photoelectrochemical water splitting has become one of the most promising solar-to-hydrogen conversion techniques. After near five-decade research, this technique has been in a dilemma that mainly results from the lack of highly efficient and stable photoelectrodes. In recent years, the stability of photoelectrodes under operation seems to be resolved by the introduction of robust TiOx protective layer, which means that ways to enhance the solar-to-hydrogen efficiency of photoelec-trodes should be developed preferentially towards the realization of solar water splitting. Improvement of the charge transfer of the photoelectrodes would lead to enhancement of the solar-to-hydrogen efficiency. Here, several main strategies for the opti-mization of charge transfer have been summarized. It is by the fabrication of micro/nano structure to facilitate charge diffuse and drift, the introduction of dopants to increase the conductivity, the optimization of synthesis procedures to minimize the charge recombination defects, the construction of semiconductor junctions and the best choice of suitable substrates for the majority charge transport or deposition of under layers that the photoelectrochemical performance of the given photoelectrode would be boosted.