Performance improvement of MXene-based perovskite solar cells upon property transition from metallic to semiconductive by oxidation of Ti3C2Tx in air
作者单位：Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education)College of PhysicsJilin University
会议名称：《第八届新型太阳能材料科学与技术学术研讨会》
会议日期：2021年
学科分类：08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学]
关 键 词：Ti3C2Tx MXene electron transport layers perovskite solar cells DFT calculations
摘 要：The unique properties of MXenes that arise from terminated functional groups and oxidization of MXenes make them attractive for application in photovoltaic devices like perovskite solar cells(PSCs). Here, oxidation of TiCT hydrocolloid was carried out to tune its properties desirable for an electron transport layer(ETL) in low-temperature processed PSCs. The calculations of the energy levels were carried out by the Vienna ab initio Simulation Package(VASP) code based on density functional theory(DFT). Oxidation of TiCT can generate Ti-O bonds and effectively reduce the defects of the film fabricated by spin-coating, while a transition from metallic material to semiconductor occurred after heavy oxidation. A better matching of energy levels between perovskite and ETL layer in the case of a hybrid of oxidized and pristine TiCT renders a champion power conversion efficiency(PCE) of 18.29 %. The improvement in PCE can be attributed to the increased electron mobility in the ETL, which promotes electron transport and reduces the electronhole recombination. Hence, by presenting a simple method for high performance in PSCs by MXene-derived materials, the work demonstrates the great potential of these materials for applications in low-temperature processed PSCs and other photovoltaic technologies.