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Series of gold and ceria supported γ-Al2O3 catalysts were developed for the oxidative esterification of methacrolein with methanol. All the catalysts were prepared through one step deposition-precipitation method, and K2CO3 and urea were used as precipitant, respectively. Au, CeO2 and γ-Al2O3 could self-assemble unique particle morphology during co-precipitation process and form semi-core shell or core shell structure after calcination. The relationship between catalytic reactivity and structural characteristics were analyzed by SEM, TEM, EDS, BET, XRD, XPS, etc. Among Au-CeO2/γ-Al2O3 (K2CO3), Au-Ce/γ-Al2O3 (Urea) and Au/γ-Al2O3 (Urea) catalysts with different active components and precipitant, the last two exhibited higher catalytic activity. Moreover, the Ce-doped catalysts shown higher stability than just Au supported on pure alumina. The active stability of the optimum Au-Ce/γ-Al2O3 catalyst was evaluated with seven-time cyclic reactions exhibiting high stability and activity with the yield of MMA above 90%.

A series of highly dispersed cobalt-based catalysts on N-doped ordered porous carbon (Co-NOPC) were synthesized using the sacrificial-template method. MCM-41, ZSM-5 and SBA-15 were employed as hard templates with 2,2′-bipyridine as the ligand. The physical and chemical properties of the Co-NOPC catalyst were characterized by Raman, XRD, SEM, TEM, EDX, ICP, BET, XPS. Co-NOPC had been proven to be a highly efficient catalyst for oxidative esterification of furfural (FUR) to methyl 2-furoate without alkaline additives. Catalytic performance was correlated to the dispersed cobalt, porous structure and specific surface area. The relationship between oxygen activation and the strong interaction of cobalt and pyridine nitrogen were confirmed by XPS. Catalytic performance enhancement mechanisms were correlated with the redistribution of electrons at the interface between carbon material and cobalt atoms through the molecular dynamics method and a reaction mechanism was also proposed. The optimized catalysts showed outstanding catalytic activity and stability and no obvious decrease in activity was found after 6 cycles with 99.6% FUR conversion and 96% methyl 2-furoate selectivity.

β- Ga2O3 films were grown by radio-frequency magnetron sputtering method. The influence of Ga2O3 buffer layers and annealing treatment on the structural, optical, morphological and electrical properties of Ga2O3 films was studied. The results revealed an improvement of crystalline quality and transmittance of annealed β- Ga2O3 films prepared with homo-buffer layers. Ga2O3 film UV photodetectors were fabricated with a new B and Ga co-doped ZnO films (BGZO)/Au interdigitated electrode. A good ohmic contact was formed between the film and the electrode. For the detector based on Ga2O3 films with buffer layers, a higher value of photo response and faster response times was obtained.

ZnTe films were prepared by close spaced-sublimation (CSS) method. The effects of substrate temperature on ZnTe films were investigated. The results showed cubic structure with strong (111) texture for all the films. Films with higher crystalline quality and larger grain size were obtained at higher substrate temperature. A red-shift of the optical bandgap and reduction of resistivity were observed with increasing substrate temperature.