The global warming issue has resulted in a great demand in zero emission power generation systems. Recently a few new concepts have been proposed that promise to achieve zero emissions while delivering unprecedentedly high efficiency. In these concepts, CO2 adsorbing material (CAM) is a key component. This paper reviews briefly the current development in CO2 adsorbing material, screens the potential materials under the conditions relevant to those in zero emission power generation systems, and identifies the best candidate and the optimum operating conditions for the production of high-purity hydrogen. It is found that CaO is thermodynamically the best candidate among metal oxides for CO2 capture in zero emission power generation systems. There exists a region within which high-purity H-2 can be produced in steam methane reforming and carbon gasification.