Simultaneous band-gap narrowing and carrier-lifetime prolongation of organic-inorganic trihalide perovskites
Simultaneous band-gap narrowing and carrier-lifetime prolongation of organic-inorganic trihalide perovskites
复制标题
DOI：
10.1073/pnas.1609030113
复制
发表时间：
2016-08-09
影响因子：
11.1
通讯作者：
Mao, Ho-kwang
中科院分区：
文献类型：
--
作者：
Kong, Lingping;Liu, Gang;Mao, Ho-kwang
有机-无机杂化三卤化铅钙钛矿材料是近年来最具吸引力的光伏材料。正如Shockley-Queisser理论所规定的那样，一个令人生畏的材料科学挑战需要进一步缩小太阳光谱中更广泛的吸收带隙，同时保持甚至协同延长载流子寿命，这是实现近带隙光电压的关键因素。在此，通过施加可控的流体静压力，我们在类似于0.3 GPa的温和压力下实现了带隙变窄和载流子寿命延长（增加高达70%至类似于100%）的前所未有的同时增强。纯混合钙钛矿上的压力诱导调制而不引入任何不利的化学或热效应，清楚地表明了带边对光子-电子相互作用的重要性，并绘制了进一步提高其光伏性能的开拓性路线。
The organic-inorganic hybrid lead trihalide perovskites have been emerging as the most attractive photovoltaic materials. As regulated by Shockley-Queisser theory, a formidable materials science challenge for improvement to the next level requires further band-gap narrowing for broader absorption in solar spectrum, while retaining or even synergistically prolonging the carrier lifetime, a critical factor responsible for attaining the near-band-gap photovoltage. Herein, by applying controllable hydrostatic pressure, we have achieved unprecedented simultaneous enhancement in both band-gap narrowing and carrier-lifetime prolongation (up to 70% to similar to 100% increase) under mild pressures at similar to 0.3 GPa. The pressure-induced modulation on pure hybrid perovskites without introducing any adverse chemical or thermal effect clearly demonstrates the importance of band edges on the photon-electron interaction and maps a pioneering route toward a further increase in their photovoltaic performance.