Photoinduced chromism of a Zinc–Iron cyanide at room temperature

Abstract

A room temperature (RT) chromism induced by illumination of ~250–450nm light was observed for the first time in a Prussian blue analog, K0.26Zn2.87[Fe(CN)6]2·7.2H2O. The photoinduced chromism is caused by the charge transfer from CN− to Fe3+ as manifested by IR and XPS measurements. Such an obvious chromic property controlled by certain optical stimuli at RT may have potential applications in optical devices.