Abstract: The teachings herein pertain to hole transporting compounds containing a cyclobutyl moiety, which can be made into organic hole conductors and into hole transporting material. Additionally, optoelectronic and photoelectrochemical devices comprising such hole transporting material or hole transporting compound are described, in particular photovoltaic devices, organic-inorganic perovskite films, layered photovoltaic devices, p-n heterojunctions, dye-sensitized solar cells, organic solar cells and solid-state solar cells. Notably, a fabricated perovskite solar cell module using a disclosed HTM compound exhibited a record efficiency over 19.0% with an active area of 30.24 cm2.