Abstract: Disclosed herein are methods and articles that include a plasmon-resonating nanostructure that employ a photo-thermal mechanism to catalyze the reduction of an oxidant. As such, the plasmon-resonating nanostructure catalyzes a redox reaction at a temperature below a predetermined activation temperature. The method can be efficiently used to catalyze the reduction of an oxidant, for example in a catalytic reactor or in a fuel cell that includes a photon source.

Abstract: Disclosed herein are photoactive compositions that include a semiconductor and plasmon-resonating nanoparticles that are capable of concentrating light at a wavelength that is substantially the same as the wavelength of light necessary to promote an electron from a valance band to a conduction band in the semiconductor. As such, the plasmon-resonating nanoparticles direct light to the band gap of the semiconductor at an increased intensity (relative to when such nanoparticles are not present). And because of that increased intensity, the photoactive composition can be more efficiently used to catalyze a photochemical reaction or generate electrical potential in a photovoltaic cell.