[1] HIU, Helmholtzstr 11, D-89081 Ulm, Germany
[2] KIT, POB 3640, D-76021 Karlsruhe, Germany
[3] New Energy & Ind Technol Org NEDO, Saiwai Ku, 18F Muza Kawasaki Bldg,1310 Omiya Cho, Kawasaki, Kanagawa 2128554, Japan
[4] US DOE, Off Energy Efficiency & Renewable Energy, 1000 Independence Ave SW, Washington, DC 20585 USA
[5] Chinese Acad Sci, Inst Phys, POB 603, Beijing 100190, Peoples R China
[6] Fed Minist Educ & Res BMBF, Key Technol Growth, Heinemannstr 2, D-53175 Bonn, Germany
[7] Argonne Natl Lab, Chem Sci & Engn Div, 9700 South, Argonne, IL 60439 USA