title: Black Magic in Gray Titania: Noble-Metal-Free Photocatalytic H2Evolution from Hydrogenated Anatase.
abstract: 'Black' TiO2-in the widest sense, TiO2reduced by various treatments-has attracted tremendous scientific interest in recent years because of some outstanding properties; most remarkably in photocatalysis. While the material effects visible light absorption (the blacker, the better), black titania produced by high pressure hydrogenation was recently reported to show another highly interesting feature; noble-metal-free photocatalytic H2generation. In a systematic investigation of high-temperature hydrogen treatments of anatase nanoparticles, TEM, XRD, EPR, XPS, and photoelectrochemistry are used to characterize different degrees of surface hydrogenation, surface termination, electrical conductivity, and structural defects in the differently treated materials. The materials' intrinsic activity for photocatalytic hydrogen evolution is coupled neither with their visible light absorption behavior nor the formation of amorphous material, but rather must be ascribed to optimized and specific defect formation (gray is better than black). This finding is further confirmed by using a mesoporous anatase matrix as a hydrogenation precursor, which, after conversion to the gray state, even further enhances the overall photocatalytic hydrogen evolution activity.
authors.affiliation: Department of Materials Science WW-4, LKO, University of Erlangen-Nuremberg, Martensstrasse 7, 91058, Erlangen, Germany.
authors.forename: Ning
authors.initials: N
authors.lastname: Liu
authors.affiliation: Department of Materials Science WW-4, LKO, University of Erlangen-Nuremberg, Martensstrasse 7, 91058, Erlangen, Germany.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Department of Materials Science WW-4, LKO, University of Erlangen-Nuremberg, Martensstrasse 7, 91058, Erlangen, Germany.
authors.forename: Nhat Truong
authors.initials: NT
authors.lastname: Nguyen
authors.affiliation: Department of Chemistry and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, Butenandtstr. 5-11, 81377, Munich, Germany.
authors.forename: Kristina
authors.initials: K
authors.lastname: Peters
authors.affiliation: Department of Chemistry and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, Butenandtstr. 5-11, 81377, Munich, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Zoller
authors.affiliation: Department of Materials Science WW-4, LKO, University of Erlangen-Nuremberg, Martensstrasse 7, 91058, Erlangen, Germany.
authors.forename: Imgon
authors.initials: I
authors.lastname: Hwang
authors.affiliation: Department of Materials Science WW-4, LKO, University of Erlangen-Nuremberg, Martensstrasse 7, 91058, Erlangen, Germany.
authors.forename: Christopher
authors.initials: C
authors.lastname: Schneider
authors.affiliation: Department of Chemistry and Pharmacy, Inorganic and General Chemistry, University of Erlangen-Nuremberg, Egerlandstr. 1, 91058, Erlangen, Germany.
authors.forename: Matthias E
authors.initials: ME
authors.lastname: Miehlich
authors.affiliation: High Pressure Laboratory, Chair of Separation Science and Technology, University of Erlangen-Nuernberg, Haberstrasse 11, 91058, Erlangen, Germany.
authors.forename: Detlef
authors.initials: D
authors.lastname: Freitag
authors.affiliation: Department of Chemistry and Pharmacy, Inorganic and General Chemistry, University of Erlangen-Nuremberg, Egerlandstr. 1, 91058, Erlangen, Germany.
authors.forename: Karsten
authors.initials: K
authors.lastname: Meyer
authors.affiliation: Department of Chemistry and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, Butenandtstr. 5-11, 81377, Munich, Germany.
authors.forename: Dina
authors.initials: D
authors.lastname: Fattakhova-Rohlfing
authors.affiliation: Department of Materials Science WW-4, LKO, University of Erlangen-Nuremberg, Martensstrasse 7, 91058, Erlangen, Germany.|Department of Chemistry, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Patrik
authors.initials: P
authors.lastname: Schmuki
mesh_terms: D002384:Catalysis; D006859:Hydrogen / Q000737:chemistry*; D006865:Hydrogenation; D055668:Photochemical Processes; D014025:Titanium / Q000737:chemistry*
chemical_list: C009495:titanium dioxide; D006859:Hydrogen; D014025:Titanium
keywords: absorption; hydrogen evolution; hydrogenation; photocatalysis; titania