Preparation And Related Performance Of Nanomaterials Based On Gallium Oxide

Environmental protection is the eternal theme of human society development,and looking for a cheap and effective way of pollutant treatment is critical in the core of this theme.In the related issues of energy and environmental protection,people are approval of photocatalysts due to its high efficiency and without any secondary pollution.It is believed that the porous nanostructured material with a high surface area can provide much improved photocatalytic activity than the common material with a low surface area.When the wide band gap semiconductor of gallium oxide was prepared into porous nanomaterial,gallium oxide of good performance can combine with porous material to provide enhanced photocatalytic performance.Porous beta-gallium oxide(?-Ga2O3)nanowires with 80-90 nm in diameter and 1.5-1.8?m in length have been successfully synthesized by a two-step route including a single-source organometallic reactant-assisted hydrothermal route and an annealing treatment.The BET characterization of the porous ?-Ga2O3 nanowires presents an average pore size of 11.94 nm and the largest surface area of 15.31 m2g-1.The photoluminescence(PL)performance indicates that there are plenty intrinsic defects in ?-Ga2O3 nanowires which also results in excellent room temperature ferromagnetism(RT-FM).The photocatalytic activity of ?-Ga2O3 was evaluated by degrading methylene blue(MB)aqueous solution and the efficiency improves obviously(about 80%)compared with the commercial powder.The enhanced photocatalytic activity can be attributed to the functional surface related defects resulting from the high surface to volume ratio and the intrinsic defects.In addition,a possible fabrication process and a photocatalytic mechanism of porous ?-Ga2O3 nanowires are proposed.In view of the good room temperature ferromagnetism and high photocatalytic efficiency,the porous ?-Ga2O3 nanowire is expected to be useful in various potential applications.Thinking of the excellent performance of porous ?-Ga2O3 nanowires,a facile route was developed to fabricate porous beta-gallium oxide nanowires(P-Ga203 NWs)-reduced graphene oxide(rGO)hybrids using?-Ga2O3 NWs and graphene oxide(GO)as raw materials.The characterization results indicate that supercritical water can act as an efficient reductant to situ-reduce GO into rGO,and porous ?-Ga2O3 NWs can further attach on the surface of as-reduced rGO through a strong coupling forces between the ?-Ga2O3 NWs and rGO.The photocatalytic performance of the hybrids could be obviously improved(about 74%)for the decomposition of methylene blue(MB)solution after coupling with 1 wt%rGO compared with the pure ?-Ga2O3 NWs.The enhanced photocatalytic activity could be attributed to the synergistic effect of extended optical absorption band,the enrichment of MB molecular on the rGO and the valid inhibition of recombination of photo-generated electron-hole pairs induced by the strong coupling interaction between rGO nanosheets and porous P-Ga203 NWs.In the preparation and performance testing process of porous?-Ga2O3 nanowires,I am very lucky to find a new photocatalytic material with novel structure and excellent performance.Orthorhombic gallium oxide hydroxide(?-GaOOH)with a novel needle-like submicron tubular structure has been firstly fabricated by an organometallic reactant-assisted hydrothermal route.A possible fabrication process indicates that the concentration of OH-ions plays an important role in the formation of submicron tube.Moreover,other four kinds of shape-controllable a-GaOOH particles of nano-,submicron-and micro-size has also been successfully synthesized by changing the pH values of solvent.The photoluminescence(PL)performance demonstrates that there are plenty intrinsic defects in ?-GaOOH.Furthermore,the photocatalytic activity of?-GaOOH with different morphologies was evaluated by degrading methylene blue(MB)aqueous solution.The efficiency of ?-GaOOH with a novel tubular structure improves obviously than other catalysts.The enhanced photocatalytic activity can be attributed to the effective inhibition of photo-generated electron-hole pair's recombination resulted from intrinsic defects.In view of the good optical properties and high photocatalytic efficiency,the ?-GaOOH tube is expected to be useful in various potential applications.