Executive Summary : | Hydrogen economy is one of the most reliable approaches to realize a green and sustainable society. Even though the combustion of hydrogen fuel has a zero emission, the current hydrogen generation technologies mostly rely on the steam reformation of the fossil fuels which emits large quantities of CO2 into atmosphere. Carbon neutral H2 generation technologies such as electrolytic cells, solar hydrogen etc. still needs much attention for the realization of sustainable energy technologies. Sufficient flow of electrons from the reductants like water upon visible light irradiation to the hydrogen evolution center is the key step for producing solar hydrogen. However, the photon flux density problems under normal solar irradiance have been existing as the critical issue for the photoinduced electron transfer from water molecules. This project is focusing on practical photocatalytic H2 evolution systems by utilizing alternative electron sources as described below, (a) Green H2 production coupled with pollutant remediation: Current fossil fuel technologies produce large amounts of toxic hydrogen sulfide during the petroleum cracking/refining processes. We develop methods to utilize toxic industrial wastes such as H2S for producing green and sustainable H2. This can be considered as one alternative reductant to bypass bottleneck issue in the solar H2 production technology. The pollutant remediation strategy by utilizing hazardous materials like H2S as the substrate for green H2 is very essential for shifting the current technologies to greener. (b) Photocatalytic transformation of Plastics into H2 and Organics: We focuses on the development of various photocatalyst materials having sufficient light induced hole potential to extract electrons from the plastics. Non-recyclable plastics can be served as the source material for H2 production by using sunlight as the energy input. (c) Integration of alternative electron sources for CO2 recycling and sustainable ammonia generation: Identification of alternative electron sources and mechanistic studies of their function as electron source for CO2 reduction and nitrogen fixation exists as the long-term perspective of the proposal. |