Lewis acid–base passivation is a significant technique to achieve structural stability of perovskite solar cells(PSCs) by overcoming the issues of wide grain boundaries, crystal defects, and the instability of PSCs. ...Lewis acid–base passivation is a significant technique to achieve structural stability of perovskite solar cells(PSCs) by overcoming the issues of wide grain boundaries, crystal defects, and the instability of PSCs. In this work, the combined effects of thiophene with phthalocyanine(Pc) as isomers(S2 and S3)on the photovoltaic performance of PSCs were studied for the first time. Through density functional theory calculations, we confirmed that the position of the S atom in the structure affects Lewis acid–base interactions with under-coordinated Pb^(2+) sites. The morphology of methylammonium lead iodide(MAPbI_(3)) for passivated devices was improved and thin dense layers with compact surface and large grain size were observed, leading to improvement of the charge extraction ability and reduction of non-radiative recombination and the trap density. A highest power conversion efficiency of 18% was achieved for the Pc S3 passivated device, which was 6.69% more than that of the controlled device.Furthermore, the Pcs passivated devices demonstrated remarkable stability under high-moisture and high-temperature conditions.展开更多
基金supported by the National Natural Science Foundation of China(21975116)the Guangdong-Hong Kong-Macao Joint Laboratory(2019B121205001)the Major Program of Guangdong Basic and Applied Research(2019B030302009)。
文摘Lewis acid–base passivation is a significant technique to achieve structural stability of perovskite solar cells(PSCs) by overcoming the issues of wide grain boundaries, crystal defects, and the instability of PSCs. In this work, the combined effects of thiophene with phthalocyanine(Pc) as isomers(S2 and S3)on the photovoltaic performance of PSCs were studied for the first time. Through density functional theory calculations, we confirmed that the position of the S atom in the structure affects Lewis acid–base interactions with under-coordinated Pb^(2+) sites. The morphology of methylammonium lead iodide(MAPbI_(3)) for passivated devices was improved and thin dense layers with compact surface and large grain size were observed, leading to improvement of the charge extraction ability and reduction of non-radiative recombination and the trap density. A highest power conversion efficiency of 18% was achieved for the Pc S3 passivated device, which was 6.69% more than that of the controlled device.Furthermore, the Pcs passivated devices demonstrated remarkable stability under high-moisture and high-temperature conditions.
