铋系列复合光催化剂的制备及其性能研究

发布时间：2018-06-23 14:33

本文选题：光催化 + 降解效率　；参考：《浙江海洋大学》2017年硕士论文

【摘要】：随着经济的高速发展,环境污染、传统能源短缺等问题日益严重,而太阳能是最直接有效的可再生能源。近年来,半导体催化降解有机污染物被认为是有效地解决上述问题的最佳途径。因此,制备简单高效的半导体催化剂一直是广大科研工作者的研究目标。本文通过溶剂法成功制备了Bi_2O_2CO_3/MWCNTs复合光催化剂、贝壳粉/Bi OI复合光催化剂,并考察了制备的催化材料的光降解性能研究。本文的主要研究内容分为以下四个方面:1)Bi_2O_2CO_3/MWCNTs复合光催化剂、贝壳粉/Bi OI复合光催化剂的制备;2)Bi_2O_2CO_3/MWCNTs复合光催化剂材料、贝壳粉/Bi OI复合光催化剂材料的表征;3)Bi_2O_2CO_3/MWCNTs复合光催化剂、贝壳粉/Bi OI复合光催化剂的性能考评;4)Bi_2O_2CO_3/MWCNTs复合光催化剂、贝壳粉/Bi OI复合光催化剂的稳定性研究。主要研究结果如下:经XRD、SEM、TEM、BET和UV-vis光谱等表征结果显示,通过水热法制备的Bi_2O_2CO_3/MWCNTs复合光催化剂具有三维花状结构,且Bi_2O_2CO_3与MWCNTs紧密地生长到一起,形成了具有较大比表面积的异质节。合成材料形成了Bi_2O_2CO_3/MWCNTs复合光催化剂。在模拟光源的情况下,降解50ml、6mg/L的罗丹明B有机污染溶液的得出纯样的Bi_2O_2CO、M/B-0.5%、M/B-1.5%、M/B-3%、M/B-5%、M/B-10%的催化效率依次为28.7%、60.9%、62.1%、80.8%、70.3%、69.2%。当MWCNTs的百分比含量达到3%的时候,制备合成的Bi_2O_2CO_3/MWCNTs复合材料的降解效率最大,其降解能力为纯样Bi_2O_2CO_3降解能力的2.8倍。对M/B-3%样品进行循环降解实验,结果表明即使在循环降解4次以后依然具有较高的光催化效率(76.7%)。说明制备的Bi_2O_2CO_3/MWCNTs复合光催化剂具有较好的光催化稳定性。通过XRD表征显示通过水热法制备的贝壳粉/Bi OI复合光催化剂中,只有S/B-10%的复合催化剂出现了贝壳粉的特征衍射峰,说明制备的复合材料中有可能形成了贝壳粉/Bi OI异质节催化剂。SEM结果进一步表明,纳米级别的贝壳粉和三维花状结构的Bi OI完美的相结合,而且形成的三维花状的Bi OI超结构并没有被破坏掉,形成了异质节。BET测定显示随着贝壳粉的加入,复合催化剂的比表面积随着增加。UV-vis谱图结果表明随着贝壳粉质量百分比的增加,贝壳粉/Bi OI复合材料的吸收波长发生红移现象,表明材料对可见光的利用率增强。经光催化降解60m L、6mg/L的罗丹明B染料溶液实验表明,贝壳粉/Bi OI复合光催化剂具有较高的催化活性。当贝壳粉含量为3%时,合成的复合材料的光催化降解能力最强,为88.43%,是纯样Bi OI降解效率值的3.5倍。四次循环降解实验后的效率为78.84%,表明制备的贝壳粉/Bi OI复合催化剂具有较好的催化稳定性。
[Abstract]:With the rapid development of economy, environmental pollution and shortage of traditional energy are becoming more and more serious, and solar energy is the most direct and effective renewable energy. In recent years, semiconductor catalytic degradation of organic pollutants is considered to be the best way to solve these problems. Therefore, the preparation of simple and efficient semiconductor catalysts has been the research goal of many researchers. In this paper, the composite photocatalyst of Bistax _ 2CO _ 2CO _ 3 / MWCNTs and the composite photocatalyst of shell powder / BiOI were prepared by solvent method, and the photodegradation properties of the prepared materials were investigated. The main contents of this paper are as follows: 1) Bi2O2CO3 / MWCNTs composite photocatalyst, shell powder / BiOI composite photocatalyst preparation 2) Bi2O2CO3MWCNTs composite photocatalyst material, shell powder / BiOI composite photocatalyst material characterization 3) Bi2O2CO3MWCNTs composite photocatalyst, Evaluation of the performance of shell powder / BiOI composite photocatalyst 4) study on the stability of BiS _ 2O _ 2CO _ 2CO _ 2CO _ 3 / MWCNTs composite photocatalyst and shell powder / BiOI composite photocatalyst. The main results are as follows: XRDX SEMTEMN BET and UV-vis spectra show that Bi2O2CO3 / MWCNTs composite photocatalyst prepared by hydrothermal method has a three-dimensional flower-like structure, and Bi2O2CO3 and MWCNTs grow closely together to form heteronodes with larger specific surface area. The synthesized materials form BiS _ 2O _ 2CO _ 2CO _ 2C _ (3) / MWCNTs composite photocatalyst. In the case of a simulated light source, the degradation of 50 ml / 6 mg / L Rhodamine B organic pollution solution resulted in the pure Bi2O2COB-0.5 / MB-1.5 and the catalytic efficiency was 28.760.962.1% and 80.870.30.33% in the order of 28.760.962.1mg / L and 69.2wt%, respectively. When the percentage content of MWCNTs reaches 3%, the biodegradable efficiency of the synthesized composite is the highest, which is 2.8 times as high as that of the pure BiS _ 2O _ 2CO _ 3. The results showed that the photocatalytic efficiency (76. 7%) was higher even after 4 times of cyclic degradation of M / B-3% samples. The results show that the prepared Bi2O2CO3 / MWCNTs composite photocatalyst has good photocatalytic stability. XRD analysis showed that in the shell powder / BiOI composite photocatalyst prepared by hydrothermal method, only S- / B-10% composite catalyst appeared the characteristic diffraction peak of shell powder. The results show that the shell powder / BiOI heterojunction catalyst. SEM results further indicate that the nanoscale shell powder and the three dimensional flower-like structure of BiOI are perfectly combined. Moreover, the three dimensional flower-like BiOI superstructure was not destroyed, and the heterojunction was formed. BET measurement showed that with the addition of shell powder, The results of UV-vis spectra show that the absorption wavelength of shell powder / BiOI composites is red-shifted with the increase of the mass percentage of shell powder, which indicates that the utilization ratio of visible light is increased. The photocatalytic degradation of 6mg / L Rhodamine B dye solution by photocatalytic degradation showed that the composite photocatalyst of shell powder / BiOI had high catalytic activity. When the content of shell powder is 3, the photocatalytic degradation ability of the composite is the highest, which is 88.43, which is 3.5 times of the pure BiOI degradation efficiency. The efficiency of the four cycle degradation experiments is 78.84, which indicates that the prepared composite catalyst of shell powder / BiOI has good catalytic stability.
【学位授予单位】：浙江海洋大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O643.36

【参考文献】