Perovskite photovoltaic is emerging as one of the most competitive solar technology due to its excellent optoelectronic property, such as high absorption coefficient, long carrier diffusion length. In view of recent advances in perovskite solar cell research, efficiency and stability are two attracting topics that is related to the commercialization of this technique. In this talk, we demonstrate a “surface patch” strategy, wherein the residual PbI2 at grain boundaries are utilized to construct the complex specie serving as the “patches”. These patches effectively suppress metal electrode diffusion and ion migration simultaneously, prolong the lifetime of perovskite solar cells substantially. Our results suggest an effective grain boundary engineering strategy to improve the stability of hybrid perovskites while maintaining its optoelectronic properties. In addition, we discussed the potential competitiveness of perovskite tandem devices, wherein the levelized cost of electricity (LCOE) is analyzed, with a sensitivity analysis by varying materials, module efficiency and life-time. It reveals the perovskite tandem PV are potentially competitive, and further efforts are required to simultaneously improve the efficiency and lifetime for perovskite PV to stand over the entire energy sector.

报告人简介：陈棋，男，北京理工大学材料学院教授，副院长。2019年获北京市杰青项目支持。2005年本科毕业于清华大学化工系，2007年硕士毕业于清华大学化学系，2012年博士毕业于加州大学洛杉矶分校(UCLA)材料科学与工程系，随后以博士后身份在UCLA加州纳米研究中心从事薄膜太阳能电池研究工作。主要从事有机无机杂化及复合材料的开发与应用研究，材料广泛应用于能源、光电等领域，具体包括太阳能电池、储能电池、传感器、探测器等各类新型光电功能化器件。承担并承担国家级项目，包括科技部重点研发计划专项和自然科学基金面上项目等。迄今发表论文90余篇，引用超过15000次。包括Science、Nature Communications、Joule、Journal of American Chemical Society、Nano Letters、Advanced Materials等。单篇最高他引超过2000次。