论文标题
B位合合对RBPBI3的电子和光电特性的影响：DFT研究
The effect of B-site alloying on the electronic and opto-electronic properties of RbPbI3: A DFT study
论文作者
论文摘要
二价阳离子混合铅卤化物钙钛矿具有增强的性能，高稳定性和降低的毒性，这对于在钙钛矿太阳能电池中持续发展是必需的。但是，并未广泛报道混合策略以寻找铅降低结构。在此，我们通过使用密度函数理论将B-stite与SN和GE合金合金，通过将B-stite适合B-stite将RBPB {1-X} MXI3的结构，电子和光学性质（其中M = {SN，GE}和X = {0.25，0.50，0.75}）报告。估计所有RBPB {1-X} MXI3（X = 0.25，0.50，0.75）的形成焓，这证实了所有结构的稳定性。已经彻底研究了状态（DOS）的能量带隙和密度。能量带隙随着SN/GE含量的增加而降低，在RBPB {1-X} GEXI3系统的情况下，在X = 0.50处观察到最低的1.850 eV。此外，还估计了所有混合系统的激子和光谱有限效率（SLME）的有效质量和结合能。观察到激子类型从Mott-Wannier变为Frenkel类型，随着B点处的SN和GE含量增加。使用含有sn/ge和pb的相等混合的活性层实现23％的最大效率。两个混合系统的估计参数与类似类型的可用文献一致。
Divalent cations mixed lead halide perovskites with enhanced performances, high stabilities, and reduced toxicity are requisite to make persistent progress in perovskite solar cells. However, the mixing strategy is not reported extensively in search of a lead reduced structure. Herein, we report the structural, electronic and optical properties of RbPb{1-x}MxI3 (where, M={Sn,Ge} and x={0.25, 0.50, 0.75}) by alloying the B-site with Sn and Ge, using the density functional theory. The formation enthalpy is estimated for all RbPb{1-x}MxI3 (with x= 0.25, 0.50, 0.75), which confirms stability for all the structures. The energy bandgap and density of states (DOS) have been thoroughly investigated. The energy bandgap decreases with the increasing Sn/Ge contents, the lowest bandgap of 1.850 eV is observed at x = 0.50 in the case of RbPb{1-x}GexI3 systems. Further, the effective masses and the binding energy of excitons and spectroscopic limited maximum efficiency (SLME) are also estimated for all the mixed systems. The exciton type is observed to change from Mott-Wannier to Frenkel type with increasing the contents of both Sn and Ge at the B-site. The maximum efficiency of 23% is achieved using an active layer containing an equal admixture of Sn/Ge and Pb. The estimated parameters of both the mixed systems are consistent with the available literature of similar types.
