石墨炔及修饰石墨炔在光电能源领域的应用

Graphyne and Modified Graphyne in the Fields of Photoelectrocatalysis and Photovoltaics

相较于石墨烯,含有sp杂化C原子的石墨炔具有天然的带隙,同时因其高载流子迁移率、π-共轭结构等优异的光电特性成为光电能源领域重要的候选材料.另外,石墨炔中炔键单元的高活性为其化学修饰与掺杂提供了良好的平台,通过修饰可以对带隙进行调节,从而使石墨炔更好地满足光电器件对半导体材料的要求,近些年来,很多研究致力于此方面并取得了重要成果.本文简要介绍了石墨炔的种类,以及γ-石墨二炔(graphdiyne,GD)的几种合成方法,对石墨炔及修饰石墨炔在光电催化及光伏领域应用的最新研究进行了综述,提出了目前研究中存在的一些问题,并对此领域未来的发展进行了展望.

Different from other members in the carbon material family, graphyne, first synthesized in 2010, has sp hybridized carbons and a natural band gap. According to many studies on optoelectronic devices, the recombination of electrons and holes is an important issue, and the excellent photoelectric properties of graphyne such as high carrier mobility and π-conjugated structure can make it an important candidate material in the fields of photocatalysis, electrocatalysis, batteries, etc. However, there are still problems remaining for the direct application of unmodified graphyne owing to its inert surface and fixed band gap. The high activity of acetylenic bond units in the graphyne provides a good platform for chemical modification and doping. Therefore, the energy band structure and semiconductor performance of graphyne can be regulated by simple solution mixing,hydrothermal reaction, and redox method to achieve material hybridization or hetero atom doping, so that the graphyne will fulfill the requirements of photoelectric devices for a semiconductor material. Many studies have been concentrated on this topic, and numerous achievements have been made over the years. In this review article,the properties and synthesis methods of graphdiyne are firstly introduced, followed by a systematic summary about the mechanism of different atomic doping changes which could help in design of precursor molecules and subsequent synthesis of graphyne derivatives. The promotion effect of graphyne hybridization on charge transfer and its specific mechanism are then detailedly illustrated. The latest research progresses of graphyne and graphyne derivatives in practical applications including photoelectrocatalysis, dye sensitized solar cell, and perovskite solar cell are further discussed, while some problems existing in the current research of this field are also listed. Our review concludes with the proposal that research focuses in the future should be shifted from theoretical calculation to specific experiment and the mechanism in the process requires better understanding, so as to push forward the studies on graphyne and further improve material properties.