Enhanced photoconductivity of layered MnIVO2 containing protonated MnIV vacancy defects had suggested new possibilities for photo-electric conversion based upon visible-light harvesting. Using spin-polarized density functional theory, the first direct evidence was provided here that such defects could indeed facilitate photoconductivity by reducing the band-gap energy and by separating electron and hole states. The results thus supported the proposition that nanosheet MnO2 offered an attractive new material for a variety of photoconductivity applications.

Defect-Induced Photoconductivity in Layered Manganese Oxides - a Density Functional Theory Study. K.D.Kwon, K.Refson, G.Sposito: Physical Review Letters, 2008, 100[14], 146601