Halide homogenization for low energy loss in 2-eV-bandgap perovskites and increased efficiency in all-perovskite triple-junction solar cells by Wang, J, Zeng, L, Zhang, D, Maxwell, A, Chen, H, Datta, K, Caiazzo, A, Remmerswaal, WHM, Schipper, NRM, Chen, Z, Ho, K, Dasgupta, A, Kusch, G, Ollearo, R, Bellini, L, Hu, S, Wang, Z, Li, C, Teale, S, Grater, L, Chen, B, Wienk, MM, Oliver, RA, Snaith, HJ, Janssen, RAJ, Sargent, EH