Controlled Synthesis Of CuO/TiO₂ Composite Catalyst And Their Study On Photocatalytic Oxidation Of Methanol To Methyl Formate

With the increasing environmental pollution and energy shortage,Environmental protection has been widely concerned.Researchers believe that photocatalytic technology can convert solar energy into chemical energy and other available energy to solve the current pollution problem.Recently,The researchers have shown that the controllable synthesis of nanomaterials with specific crystal surface or heterojunction composite catalytic materials can promote the separation of photogenerated electrons and holes,and then improve the activity of the catalyst.TiO₂ has a good catalytic activity for photocatalytic oxidation of CH₃OH to HCOOCH₃.However,the traditional TiO₂ is mostly spherical nanoparticlzes,and the efficiency of separation of photogenerated electrons and holes is low,which limits the improvement of photocatalytic performance.At present,the main research work is focused on the modification of spherical TiO₂ nanoparticles,and rarely involves the change of the morphology of TiO₂.The research result have shown that the co-catalyst deposited on the surface of TiO₂ can form a heterojunction interface,and the heterojunction interface can promote the separation of photogenerated electrons and holes.Therefore,in this thesis,CuO catalyst was deposited on anatase TiO₂ spindles and anatase TiO₂nanotubes respectively,and CuO/TiO₂ heterojunction composite catalyst was constructed.The synergistic effect of crystal plane effect and heterojunction effect was utilized to maximize the separation of photogenerated electrons and holes.And then achieve the efficient conversion of methanol to methyl formate.Under light conditions,at25℃,7%CuO/TiO₂ spindles gave 97%methanol conversion and 83%methyl formate selectivity and 7%CuO/TiO₂ nanotubes was 94%methanol conversion and the selectivity of HCOOCH₃ was 90%.