Preparation Of Catalytic Films With Micro/Nanostructures Using ZnO Nanorods As Template And Their Catalytic Applications

The method of preparation of catalytic films with micro/nanostructures using ZnO nanorods as template is extremely attractive because of their a lot of advantages. However, there are still a number of challenges, such as, how to fabricate a variety of films with micro/nanostructures in different materials using ZnO as template, which has outstanding performance. It is always the hot topic in research direction. In the present dissertation, we focused on developing the approach of preparation of catalytic films with micro/nanostructures using ZnO nanorods as template and studying their unique properties. Following is the brief introduction.(1) Template-assisted evaporation deposition of Au nanoparticles for fabrication of hierarchical porous Au film modified electrodes and their salt concentration-dependent capacitive currentWe report facile fabrication of three dimensionally hierarchical porous Au film modified electrodes by solvent evaporation deposition of Au nanoparticles (NPs) on a ZnO nanorods (NRs) template followed by template removal. The utilization of the small micropores within the hierarchical porous Au architectures could be altered by salt concentrations, leading to the salt concentration-dependent interfacial capacitances. Such fundamental investigation on the electrochemical properties of the as-prepared hierarchical porous Au film modified electrodes is of particular importance for their potential applications in catalysis and sensing.(2) Substrate-independent and large-area synthesis of carbon nanotube thin films using ZnO nanorods as template and dopamine as carbon precursorWe introduce a method for large-area and substrate-independent synthesis of the big-inner-diameter carbon nanotube (BIDI-CNT) thin films by utilizing polydopamine (PDA) as carbon source and ZnO nanorods (NRs) as sacrificing template for the first time. ZnO NRs with hexagonal morphology were coated with PDA filmsviathe ammonium per sulfate-induced polymerization of dopamine at neutral pH for avoiding the degradation of amphoteric ZnO at alkaline pH needed by the conventional oxygen-induced polymerization of dopamine. After carbonization in N2atmosphere at500℃followed by ZnO removal, the hollow BIDI-CNTs with tuned wall thickness and hexagonal morphology were obtained. In addition, the obtained BIDI-CNTs were found to be N-doped. Furthermore, on the base of the outstanding substrate-independent growth properties of both ZnO NRs and PDA, the large area thin films of the N-doped BIDI-CNTs could be synthesized on various solid substrates.(3) Preparation of catalytic films of the Au nanoparticle-carbon composite tubular arraysWe have demonstrated for the first time the fabrication of catalytic films comprising the catalyst NP-embedded pBIDI-CNT arrays with AuNPs as a model. The obtained catalytic films exhibited good catalytic activity and offered the feasibility and ease of multiple reuse. Because of the outstanding adhesion property of PDA and its temp late-directed carbonization ability, this approach can be applied to introduce other NPs, regardless of their sizes and chemical compositions, inside the arrayed pBIDI-CNTs to produce catalytic films for NP-catalyzed applications.