Nanoengineered surfaces/interfaces/coatings and novel

materials for applications in Energy and Environment

SU-IL IN

Department of Energy Systems Engineering, DGIST

12 April, 2013 (Fri), 4PM / #1101, W1-3 Bldg.

The development of solar powered photo-activated materials promises to have a major impact in a variety of future applications in environmentally friendly science, such as solar energy conversion (solar fuel and photoelectrocatalysis), self-cleaning, air/water purification and artificial photosyntheiss. For this research various photocatalytic experimental systems have been designed and constructed to conduct gas/solid heterogeneous photocatalytic reactions in the UV-Vis region. Simultaneously visible light activated materials such as anion-doped TiO2 have been successfully prepared by chemical and/or physical synthetic techniques [1]. Currently a multi-template strategy for synthesizing hollow nanocubes of CuO-TiO2-xNx, a new hybrid material that photocatalytically converts CO2 into methane under solar irradiation, has been developed [2]. In addition this talk will review researches related to the direct conversion of solar energy to chemical fuels (i.e.,hydrogen) utilizing a combination of a visible or infrared light absorber such as Si with non-Pt hydrogen evolution reaction (HER) catalysts such as cubanes made of MoxSy. Prof. Chorkendorff and et al. showed that the bioinspired molecular co-catalysts such as incomplete cubane-like clusters (Mo3S4) efficiently catalyze the evolution of hydrogen when coupled to a p-type Si semiconductor that harvests red photons in the solar spectrum. The current densities at the reversible potential match the requirement of a photoelectrochemical hydrogen production system with a solar-to-hydrogen efficiency in excess of 10% [3].

[1] S. –I. In et al., Journal of the American Chemical Society, 2007, 129 (45), 13790-13791.

[2] S. –I. In et al., Angewandte Chemie International Edition, 2012, 51, 3915-3918

[3] Ib Chorkendorff et al., Nature Materials, 2011, 10, 434-438