Controlling charge flow by managing electron holes
(PHYSorg.com Chemistry)

Much remains to be learned about how charge moves along the molecules that make up the layers of materials in solar cells. These details have remained hidden because of the challenges of direct, real-time observation of motion of electrons and their holes at interfaces where two solar-cell materials meet. Using ultrafast extreme ultraviolet pulses, researchers watched as holes were injected across the interface materials found in hybrid perovskite solar cells. The bursts of extreme ultraviolet light were only femtoseconds in duration. The bursts allowed ultrafast, element-specific measurements. The experiments revealed what states of the nickel atom are the primary hole-acceptors.