Hybrid density functional theory calculation of orthorhombic CsPbI3-3xBr3x and CsPbBr3-3xCl3x

초록

We investigated the stability and the electronic structure of mixed halide perovskite including CsPb(I1-xBrx)(3) and CsPb(Br1-xClx)(3). To model mixed halide perovskites, random structures were generated, and relaxed at the generalized gradient approximation (GGA) level calculation with van der Waals correction. The stability of alloys was discussed in terms of the mixing enthalpy. The electronic band gap of alloys was obtained by using both GGA and hybrid density functional. The hybrid density functional theory calculation shows better agreement with the experimental band gap. We also found that the electronic band gap can be obtained cost-effectively by using a reduced k-point grid for the Fock exchange potential.

키워드