title: Synthesis of copper hydroxide and oxide nanostructures via anodization technique for efficient photocatalytic application.
abstract: We have demonstrated a facile protocol for synthesizing CuO and Cu2O mixed-phase nanostructures by anodization of copper hydroxide (Cu(OH)2) nanoneedles and their heat treatment in different atmospheres, which affect photocatalytic degradation efficiency. The oxygen annealed sample had relatively small (100 nm) lamellar, spherical nanoparticulate structures on the substrate surface, which showed better photocatalytic degradation of reactive black 5 dye resulting from the appropriate morphology and phase formation, compared to the samples annealed in different atmospheres and vacuum. The pseudo first-order rate constant (k) of the oxygen annealed sample was 0.0054/min, which was relatively high due to the formation of a CuO-Cu2O heterojunction with matching band potentials. Air, nitrogen, argon and vacuum annealing resulted in bigger particles and different morphologies, which led to pseudo first-order rate constants (k) of 0.0032/min (air-annealed); 0.0021/min (N2-annealed); 0.0033/min (Ar-annealed); and 0.0027/min (vacuum-annealed), which resulted in poor photocatalytic degradation of the reactive black 5 dye.
authors: Department of Materials Science and Engineering, Korea University, Seoul 136-713, Korea.
authors: Rajeshkumar Shankar
authors: RS
authors: Hyam
authors: Jongseok
authors: J
authors: Lee
authors: Eunju
authors: E
authors: Cho
authors: Jeehyeong
authors: J
authors: Khim
authors: Haigun
authors: H
authors: Lee
mesh_terms: D003300:Copper; D003460:Crystallization / Q000379:methods*; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006878:Hydroxides / Q000138:chemical synthesis*; D008027:Light; D046911:Macromolecular Substances / Q000737:chemistry / Q000528:radiation effects; D008968:Molecular Conformation / Q000528:radiation effects; D049329:Nanostructures / Q000737:chemistry* / Q000528:radiation effects / Q000648:ultrastructure*; D010087:Oxides / Q000138:chemical synthesis*; D010316:Particle Size; D010777:Photochemistry / Q000379:methods; D013499:Surface Properties / Q000528:radiation effects
chemical_list: D006878:Hydroxides; D046911:Macromolecular Substances; D010087:Oxides; C508959:copper hydroxide; D003300:Copper