Copper oxides 4 Oxidation 4 Scanning electron microscopy 4 Temperature-programmed reduction (TPR) 4 Binary oxides 2 CO preferential oxidation 2 Carbon monoxide 2 Carbonates 2 Catalyst activity 2 Catalyst selectivity 2 Catalysts 2 Cerium 2 Cerium compounds 2 Composition effects 2 Copper 2 Coprecipitation 2 Crystal lattices 2 Doping (additives) 2 Heat treatment 2 Hydrogen 2 PEM fuel cells 2 Preferential oxidation 2 Proton exchange membrane fuel cells (PEMFC) 2 Pyrolysis 2 Redox reactions 2 Reduction 2 Solutions 2 Temperature programmed reduction (TPR) 2 Temperature range 2 Thermal effects 2