%0 Journal Article %T Constructive Effects of Alkyl Chains: A Strategy to Design Simple and Non‐ Spiro Hole Transporting Materials for High‐ Efficiency Mixed‐ Ion Perovskite Solar Cells %A %A %A %A Hadadian, Mahboobeh %A %A %A %A %A %A %A %A %J Advanced Energy Materials %@ 1614-6832 %D 2016