Effect Of Au,Cu And Cu Oxide Modification On Photocatalytic Activity Of TiO₂

As environmental and energy issues get more serious,it's becoming increasingly important to study high quality and efficient photocatalytic technologies and corresponding materials.Among them,titanium dioxide?TiO₂?materials have been favored by researchers around the world,due to the high physicochemical stability,environmental friendliness and excellent catalytic activity.But so far,the application of TiO₂ has not been widely commercialized.Research on the improvement and expansion of its performance is still in progress.In this thesis,we propose a versatile and simple method to prepare a composite of gold and titanium dioxide,as well as a composite of copper and copper oxides and titanium dioxide.We expect this compound could increase the photocatalytic activity of the sample and broaden its response band.Firstly,Au nanoparticles?NPs?@TiO₂ nanotube arrays?NTAs?heterostructured films with enhanced H₂ generation rate under full spectrum were synthesized,using a controllable and facile dip-loading approach.Size of the Au NPs was well-distributed around 7 nm,and the TiO₂ NTAs were found vertically aligned.Due to LSPR effect and Schottky contact,the as-prepared Au NPs@TiO₂ NTAs heterostructured films exhibited improved H₂ generation abilities as well as photocatalytic degradation abilities.H₂evolution rate of the obtained samples?effective area:5.25 cm²?reached 74.56?mol/h,which was 38 times higher than that of the raw TiO₂ NTAs.And the Au NPs@TiO₂ NTAs samples also showed an obvious advantage over the raw TiO₂ NTAs,in methyl orange degradation under UV illumination.Repetition experiments were further carried out to ensure the dip-loading method was a reliable fabrication process.Besides,based on highly-ordered TiO₂ nanotube arrays?NTAs?,we successfully fabricated the Cu₂O-TiO₂ NTAs heterojunction by a simple thermal decomposition process for the first time.The anodic TiO₂ NTAs were functioned as both“nano-container”and“nano-reactors”to load and synthesize the narrow-band Cu₂O nanoparticles.The loaded Cu₂O expanded absorption spectrum of the TiO₂ NTAs from ultraviolent range to visible light range.We found that the Cu₂O-TiO₂ NTAs heterojunction films had visible activities towards photocatalytic degrading methyl orange?MO?.The photocatalytic abilities of the Cu₂O-TiO₂ NTAs heterojunction films were found increased with the Cu₂O content from 0.05 mol/L to 0.3 mol/L.Here we put forward this promising method,hoping it can facilitate the mass production and applications of Cu₂O-TiO₂ NTAs heterojunction.