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271.
非晶态TiO2-W薄膜的光催化性能研究 总被引:2,自引:0,他引:2
采用磁控溅射技术在玻璃基片上制备了W掺杂的非晶态TiO2薄膜,用XRD、XPS和椭圆偏光测厚仪等对薄膜进行了微观分析.结果表明,TiO2-W薄膜为非晶态结构.Ti以 4价存在;W以0价和 6价形式存在,并且6价和0价W的原子浓度比为6.4:1;薄膜中Ti和W的原子浓度比为2.6:1.对5 mg·L-1的亚甲基蓝溶液光催化脱色试验表明,随着膜厚的增加,光催化降解率递增,当膜厚达到141 nm时,所制备的TiO2-W薄膜对亚甲基蓝的脱色率在2 h达到90%;当膜厚大于141 nm时,光催化降解率不再增加. 相似文献
272.
《环境科学学报(英文版)》2023,35(3):349-361
At present, the high re-combination rate of photogenerated carriers and the low redox capability of the photocatalyst are two factors that severely limit the improvement of photocatalytic performance. Herein, a dual Z-scheme photocatalyst bismuthzirconate/graphitic carbon nitride/silver phosphate (Bi2Zr2O7/g-C3N4/Ag3PO4 (BCA)) was synthesized using a co-precipitation method, and a dual Z-scheme heterojunction photocatalytic system was established to decrease the high re-combination rate of photogenerated carriers and consequently improve the photocatalytic performance. The re-combination of electron-hole pairs (e− and h+) in the valence band (VB) of g-C3N4 increases the redox potential of e− and h+, leading to significant improvements in the redox capability of the photocatalyst and the efficiency of e−-h+ separation. As a photosensitizer, Ag3PO4 can enhance the visible light absorption capacity of the photocatalyst. The prepared photocatalyst showed strong stability, which was attributed to the efficient suppression of photo-corrosion of Ag3PO4 by transferring the e− to the VB of g-C3N4. Tetracycline was degraded efficiently by BCA-10% (the BCA with 10 wt.% of AgPO4) under visible light, and the degradation efficiency was up to 86.2%. This study experimentally suggested that the BCA photocatalyst has broad application prospects in removing antibiotic pollution. 相似文献
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274.
经溶胶-凝胶法制备不同镧(La)掺杂量的二氧化钛(TiO2),得到光催化转化吸附回收有机磷的复合材料.结果表明,La与TiO2掺杂物质的量比为0.002并经过煅烧和掺杂物质的量比为0.02未经煅烧的2种材料,以6:4的比例混合,所得复合材料La@TiO2(6:4)为粒径约13nm的锐钛矿型TiO2,表面有球形聚集体但分布较均匀,其光谱范围较纯TiO2发生红移,因而光催化效率提高.当有机磷浓度20mg/L、La@TiO2(6:4)投加量为1g/L、溶液pH值为9时,有机磷回收率最高达85%.溶液中的NO3-、Cl-、SO42-对磷回收影响不大,CO32-有抑制作用;材料经解吸后可多次重复利用.研究表明La@TiO2(6:4)为有前景的有机磷回收复合材料. 相似文献
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设计了1种流化床光催化氧化中试处理系统,制备了一种负载型TiO2光催化剂.以高压汞灯为光源,选用难降解偶氮染料4BS和高分子化学浆料CMC配制的模拟印染废水为处理对象,考察了初始pH值、初始浓度以及光助催化剂H2O2浓度、Fe3+浓度对光催化降解效果的影响,并对有关的光催化反应动力学规律进行了探讨.结果表明,本工艺系统对配制的印染废水有较好的处理效果,光照74min色度去除率可超过80%,光照150min COD去除率可超过70%,BOD5/COD可提高至0.4以上. 相似文献
277.
Aqueous solutions of azo dyes undergo degradation to form harmless intermediates and colorless products following irradiation by visible light in the presence of titanium dioxide thin films. The dyes that were studied in this work are: Chicago Sky Blue 6B and Benzopurpurin 4B. Results obtained indicated that complete mineralization of the dyes took place under the experimental conditions. There was an increase in conductivity after the complete mineralization experiments possibly indicating the formation of ions such as NO3^- and SO4^2-. Chemical oxygen demand(COD) measurements show a decrease in organic matter for both dyes following complete degradation. The effect of how changing experimental conditions such as pH, temperature and starting concentrations of dyes affected the rate of dye degradation was measured. There was an increase in the rate of disappearance of the dye color at lower pH. High concentrations of dye solutions reauired Iona dearadation time. 相似文献
278.
Degradation of dyestuff wastewater using visible light in the presence of a novel nano TiO2 catalyst doped with upconversion luminescence agent 总被引:3,自引:0,他引:3
WANG Jun WEN Fu-yu ZHANG Zhao-hong ZHANG Xiang-dong PAN Zhi-jun ZHANG Lei WANG Lei XU Liang KANG Ping-li ZHANG Peng 《环境科学学报(英文版)》2005,17(5):727-730
IntroductionEvery year ,the dyeing processes and dye productionbring large amounts of wastewaters containing highconcentration poisonous organic compounds ( Neppolian,2002 ; An, 2002) . If not being treated properly andbetimes , the wastewaters will serio… 相似文献
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