Synthesis Of Porous Cu₂O Nanospheres With Photocatalytic Performance In Visible Light

As a typical p-type semiconducting material, cuprous oxide（Cu₂O） possesses a stable, direct band gap of about 2.0 to 2.2 eV, which is a kind of the visible light response of photocatalysis, and in theory energy conversion absorption coefficient is up to 18 % in the visible light, and which which has wide-scale applications in gas sensors, solar cells and lithium-ion batteries owing to its unique optical and magnetic properties.It has high catalytic activity, non-toxic and low preparation cost, can be directly used to sunlight degradation of organic matter, does not produce secondary pollution, the theory of utilization is very high, is a great development prospects of green visible light catalyst.In this paper copper acetate was used as the Cu2+ source, Silk Sericin（SS） as the soft template and stabilizing agent. Synthesis of cuprous oxide by chemical coprecipitation method. To investigate the concentration of Silk Sericin, the pH value of reaction system and reaction time the influence of the structure and morphology on the Cu₂O/SS nanosphere particles, the cationic dye methyl orange（MO） as the simulation of organic pollutants, using the preparation of photocatalyst on photocatalytic degradation of MO in visible light, to investigate the photocatalytic performance of porous Cu2 O nanosphere particles. This topic research work includes the following three aspects:（1） The preparation of Cu₂O/SS nanosphere particles: the copper acetate was used as the Cu2+ source, Silk Sericin（SS） as the soft template and stabilizing agent,Glucose as reducing agent, synthesis of cuprous oxide by chemical coprecipitation method. To investigate the concentration of Silk Sericin, the pH value of reaction system and reaction time have influence of the structure and morphology on the Cu₂O/SS nanosphere particles. The results showed that the best concentration of copper acetate and Silk Sericin were 3.5 M and 1.67 wt%, respectively. And the pH value of reaction system was 12, the Cu₂O/SS nanosphere particles size was minimum,about 500-600 nm.（2） Preparation and characterization of porous Cu2 O nanosphere particles: Made the Cu₂O/SS composite nanosphere particles in a nitrogen atmosphere circulation,then, under a certain temperature under nitrogen atmosphere calcining 2 h, the heating and cooling rate is 5 ℃ / min. Synthesis of porous Cu2 O nanosphere particles. To investigate the temperature of the calcined have influence of the structure and morphology on the porous Cu2 O nanosphere particles, Choose the three temperature following: 350 ℃, 450 ℃, 550 ℃, respectively. The results showed that the best calcination temperature was 350 ℃, in this temperature the porous Cu2 O nanosphere particles have more porous, and the size distribution of uniform, and smaller than before for calcination（3） The photocatalytic activity test of porous Cu2 O nanosphere particles: the cationic dye methyl orange（MO） was used to simulate organic pollution sources,comparison of all kind of preparation of Cu2 O nanoparticles degradation performance in visible light. The results showed that the photocatalytic degradation rate of porous Cu2 O nanoparticles can reach 99.87 %, and the pure octahedral Cu2 O is 83.42 %,increased by 16.45 %.In this paper copper acetate was used as the Cu2+ source, Silk Sericin（SS） as the soft template and stabilizing agent, Synthesis of cuprous oxide by chemical coprecipitation method. Provides a preparation of large surface area, particle size adjustable, stable performance of the porous Cu2 O nanosphere materials of new ideas and new methods; Broaden the application fields of silk sericin protein industrial waste, achieved with sericin silk high ecological value of waste recycling, opens a new method to sewage pollution. This method will be to promote the high value and comprehensive utilization of waste resources and water pollution control has important scientific and practical significance.