论文标题
卤化物钙钛矿:第三代光伏材料由元素粘合授予
Halide perovskites: third generation photovoltaic materials empowered by metavalent bonding
论文作者
论文摘要
第三代光伏(PV)材料结合了许多有利的特性,包括高光吸收和大电荷载体迁移率,这是由小有效质量促进的。目前,卤化物钙棍(ABX3,其中X是I,Br或Cl)似乎是目前最有前途的第三代PV材料。它们的光电特性由B-X键控制。量子化学键分析表明,该键与离子,金属或共价键明显不同。取而代之的是,它更好地将其视为荟萃的,因为它在相邻原子之间共享大约一个p电子。所得的Sigma键是半填充的,这会引起明显的光吸收。电子传递和晶格扭曲打开了一个中等的带隙,导致载有较小质量的电荷载体。因此,元粘结解释了卤化物钙钛矿的有利的PV特性。这是在不同键类型的地图中汇总的,这为设计第三代PV材料提供了蓝图。
Third-generation photovoltaic (PV) materials combine many advantageous properties, including a high optical absorption together with a large charge carrier mobility, facilitated by small effective masses. Halide perovskites (ABX3, where X is I, Br or Cl) appear to be the most promising third-generation PV materials at present. Their opto-electronic properties are governed by the B-X bond. A quantum-chemical bond analysis reveals that this bond differs significantly from ionic, metallic or covalent bonds. Instead, it is better regarded as metavalent, since it shares approximately one p-electron between adjacent atoms. The resulting sigma-bond is half-filled, which causes pronounced optical absorption. Electron transfer and lattice distortions open a moderate band gap, resulting in charge carriers with small effective masses. Hence metavalent bonding explains the favorable PV properties of halide perovskites. This is summarized in a map for different bond types, which provides a blueprint to design third-generation PV materials.