Masakazu Yamagiwa

Crucial role of sustainable liquid junction potential for solar-to-carbon monoxide conversion by a photovoltaic photoelectrochemical system

Solar energy conversion to carbon monoxide (CO) is carried out using a wired photovoltaic photoelectrochemical (PV PEC) system under simulated solar light irradiation. The PV PEC system promotes CO generation from carbon dioxide and water with approximately 2.0% solar-to-CO conversion efficiency (ηCO) for 2 h. This is achieved via contributions from electrolyte conditions, which generate a sustainable liquid junction potential, in addition to the combination of efficient visible light absorption by a triple-junction amorphous silicon PV cell with high electrode activities with low overpotentials. Estimations of energy conversion efficiency based on the electrochemical properties of the PV cell and electrodes exhibit that the liquid junction potential makes a huge contribution to ηCO. Moreover, the liquid junction potential created by bubbling two kinds of carrier gases produces sustainable chemical bias. This system may contribute to new strategies for the development of sustainable artificial photosynthesis.

Fabrication of metal core and organic shell nanoparticle packing film for plasmon polariton waveguide

Core-shell Au nanoparticles were synthesized for chemical reaction under mild liquid phase condition. The nanoparticles film was fabricated on a glass substrate for surface plasmon polariton waveguide. The nanoparticle piled up on the substrate made a smooth surface. A waveguide was easily fabricated by the lift-off method and the patterned trench filled method.