单 位：
生物质材料科学与技术教育部重点实验室(东北林业大学)
摘 要：
二氧化钛(TiO_2)在污水处理领域被广泛关注,然而团聚失活、回收困难和自然光利用率低等问题使其应用受到限制。本研究致力于提高TiO_2的光响应范围、光催化活性并解决其难以回收的问题。采用水热法制备了以木材为基底的TiO_2/木材复合材料,探讨了不同掺杂量的稀土钇对TiO_2/木材复合材料光催化性能的影响,并对制备的复合材料从晶体结构、表面形貌、组分含量、表面官能团、吸光度等方面进行表征测试,通过降解模拟污染物甲基橙溶液探讨复合材料的光催化性能。研究结果表明,负载于木材表面的TiO_2均为锐钛矿型,且均匀负载在木材基体表面;稀土钇的掺杂能够起到细化晶粒的作用,晶粒最小可达9 nm,较小的晶粒尺寸可使以木材为基底的TiO_2具有更大的受光面积,进而达到提高材料光催化性能的目的;此外,稀土钇的掺杂扩大了TiO_2的光谱响应范围,使复合材料对光的吸收波长发生红移;以20 mg/L甲基橙溶液作为目标污染物,经过长弧氙灯光照240 min后,掺杂稀土钇的摩尔分数为1%的复合材料光催化效果最为明显,甲基橙降解率达到75%。本研究制备的复合材料将木材的环境友好特性与TiO_2优异的光催化性能相结合,为光催化处理污水及生物质基复合材料的制备提供了思路。
译 名：
Preparation of wood-based yttrium doped TiO_2 film and its photocatalytic properties
作 者：
WANG Jiawei;HU Xiaoyang;LI Mingjian;SHAO Linzhi;ZHAN Jianfeng;Key Laboratory of Bio-based Material Science and Technology (Northeast Forestry University),Ministry of Education;
关键词：
titanium dioxide;;wood;;yttrium doping;;hydrothermal processing;;photocatalytic
摘 要：
Titanium dioxide(TiO_2) has been widely used in the field of wastewater treatment due to its non-toxic and harmless properties to organisms, stable chemical properties, low cost and high photocatalytic activity under ultraviolet light. Moreover, the photocatalytic performance of TiO_2 modified by metal or non-metal doping is significantly improved. However, the application of TiO_2 has been limited because the utilization rate of natural light is low and its particles are too fine, easy to deactivate and agglomerate in the use environment, hard to deposit, resulting in difficulty being separated, recycled and reused. This experiment aimed at expanding the photoresponse range of TiO_2, improving the photocatalytic activity and solving the problem of difficult recovery of traditional suspended phase TiO_2. In this study, wood based TiO_2/wood composite materials were prepared by the hydrothermal processing, and the impacts of different doping amounts of rare earth yttrium on the photocatalytic properties of TiO_2/wood composite materials were investigated. The X-ray diffraction(XRD), scanning electron microscope(SEM), energy dispersive X-ray spectroscopy(EDS), Fourier transform infrared spectroscopy(FT-IR) and UV-vis spectroscopy were used to characterize the composite material's crystal structure, surface morphology, component content, surface functional group, absorbance and other aspects, and the photocatalytic performances of the composites were explored through the degradation of simulated pollutant methyl orange(MO) solution. The TiO_2 loaded on the wood surface was anatase type and uniformly loaded on the wood matrix surface. The minimum grain size was up to 9 nm, the smaller grain size enabled the wood-based TiO_2 to have a larger light-receiving area, thus achieving the purpose of improving the photocatalytic performance of the material. At the same time, the doping of rare earth yttrium could also expand the spectral response range of TiO_2, resulting in the red shift of light absorption wavelength of the composite. Using the 20 mg/L methyl orange solution as the target pollutant, the photocatalytic effect of the composite material with a molar fraction of 1% rare earth yttrium doped was the most significant one after being illuminated by a Xe-lamp for 240 min, and its degradation rate reached 75%. The composite materials prepared in this experiment combined the environmental friendliness of wood with the excellent photocatalytic performance of TiO_2. Wood could provide a low-cost and sustainable carrier for the synthesis of TiO_2. At the same time, this experiment provided a simple, green and sustainable new idea for the photocatalytic treatment of wastewater and the preparation of biomass-based composites.
