12. Plasmon-Induced Carrier Transfer for Infrared Light Energy Conversion

The infrared (IR) region of the solar spectrum is a source of untapped potential energy. Conversion of IR-light to electrical energy or fuel would provide a plentiful energy source for modern society. Plasmonic energy conversion holds the key to conversion of solar energy through materials that efficiently absorb photons of the desired wavelength, including the IR region. Herein, we investigated plasmon-induced carrier transfer from plasmonic heavily doped semiconductor nanocrystals in a wide bandgap semiconductor to convert IR-light to energy. We discovered that efficient hot-carrier transfer proceeds from a heavily doped semiconductor nanocrystal to a wide bandgap semiconductor upon excitation of a localized surface plasmon resonance band. In addition, this material system achieved photocatalytic H₂ evolution based on excitation at long wavelengths of the solar spectrum (i.e., 2500 nm). The apparent quantum yield of photocatalytic H₂ evolution based on a catalyst with a plasmonic heavily doped semiconductor as a light-harvesting material represents a highly efficient conversion of IR energy to fuel. The relationship between the plasmon-induced carrier dynamics and photocatalytic activity paves the way for use of this undeveloped low-energy light as a solar energy resource.