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991.
Novel Bi2MoO6 Nanosheets/Vertical TiO2 Nanorods Arrays Heterojunction with Enhanced Photoelectrochemical Performance under Visible Light Irradiation 下载免费PDF全文
Xiang Gao Jia-wei Xue Ying Luo Xiao-di Zhu Song Sun Jun Bao Wen-dong Wang 《化学物理学报(中文版)》2017,30(5):576-580
Novel Bi2MoO6/TiO2 heterojunction was fabricated by growing Bi2MoO6 nanosheets arrays on the vertically aligned TiO2 nanorods arrays via a two-step solvothermal method. The obtained Bi2MoO6/TiO2 hierarchical heterojunction showed excellent visible light photoelectrochemical performance. Compared with the pure TiO2 and Bi2MoO6, the photocurrent density of the heterojunction was increased 57 and 29 times, respectively. Furthermore, the hydrogen generation rate of the Bi2MoO6/TiO2 for photoelectrocatalytic water-splitting was about 6 times higher than that of the pure Bi2MoO6. The improved performance can be attributed to the synergistic effects of enhanced absorption of visible light, increase of migration rate and separation efficiency of photo-induced carriers. 相似文献
992.
《化学:亚洲杂志》2017,12(4):387-391
Facilitating charge‐carrier separation and transfer is fundamentally important to improve the photocatalytic performance of semiconductor materials. Herein, two‐dimensional hexagonal WO3 nanoplates were synthesized by a two‐step route: rapid evaporation and solid‐phase sintering. The as‐prepared WO3 exhibits an enhanced activity of photocatalytic water oxidation compared to bulk monoclinic WO3. The electron dynamics analysis reveals that a more efficient charge‐carrier separation in the former can be obtained, the origin of which can be attributed to an increased number of surface defects in hexagonal WO3 nanoplates. This work not only presents a novel and simple method to produce two‐dimensional hexagonal WO3 nanoplates, but also demonstrates that surface defects and two‐dimensional geometric structures can promote the charge separation, which may be extended to the design of other efficient photocatalysts. 相似文献
993.
《Angewandte Chemie (International ed. in English)》2017,56(1):409-412
Heteroaromatic sulfoxides are a frequent structural motif in natural products, drugs, catalysts, and materials. We report a metal‐free visible‐light‐accelerated synthesis of heteroaromatic sulfoxides from sulfinamides and peroxodisulfate. The reaction proceeds at room temperature with blue‐light irradiation and allows the C−H sulfinylation of electron‐rich heteroarenes, such as pyrroles and indoles. An electrophilic aromatic substitution mechanism is proposed based on the substrate scope, substitution selectivity, and competition experiments with different nucleophiles. 相似文献
994.
995.
电化学传感器在用于细胞实时监测过程中,电极界面污染严重影响其检测性能.通过将纳米光催化剂与电化学传感材料复合,构建光致清洁电化学传感器,为电极界面的高效及无损更新提供了新思路.然而光催化产生的活性氧自由基导致细胞损伤,限制了细胞培养及检测过程中电极界面的实时更新.为此,我们在PEDOT@CdS/TiO2/ITO可见光致更新电极表面旋涂明胶薄层,在保持电极良好的光致清洁和电化学传感性能同时,利用明胶薄层阻碍光催化产生的活性氧自由基扩散至细胞表面,显著降低了细胞损伤.此外,明胶优良的生物相容性有利于细胞的黏附及增殖.利用该电极,我们实现了人脐静脉内皮细胞(HUVECs)培养过程中,电极的在线更新以及细胞释放一氧化氮的实时监测. 相似文献
996.
Mubashir Hussain Zhen Chen Mu Lv Jingyi Xu Xiaohan Dong Jingzhou Zhao Song Li Yan Deng Nongyue He Zhiyang Li Bin Liu 《中国化学快报》2021,31(12):3163-3167
The rapid identification of pathogens is crucial in controlling the food quality and safety. The proposed system for the rapid and label-free identification of pathogens is based on the principle of laser scattering from the bacterial microbes. The clinical prototype consists of three parts: the laser beam, photodetectors, and the data acquisition system. The bacterial testing sample was mixed with 10 mL distilled water and placed inside the machine chamber. When the bacterial microbes pass by the laser beam, the scattering of light occurs due to variation in size, shape, and morphology. Due to this reason, different types of pathogens show their unique light scattering patterns. The photo-detectors were arranged at the surroundings of the sample at different angles to collect the scattered light. The photodetectors convert the scattered light intensity into a voltage waveform. The waveform features were acquired by using the power spectral characteristics, and the dimensionality of extracted features was reduced by applying minimal-redundancy-maximal-relevance criterion (mRMR). A support vector machine (SVM) classifier was developed by training the selected power spectral features for the classification of three different bacterial microbes. The resulting average identification accuracies of E. faecalis,E. coli and S. aureus were 99%, 87%, and 94%, respectively. The overall experimental results yield a higher accuracy of 93.6%, indicating that the proposed device has the potential for label-free identification of pathogens with simplicity, rapidity, and cost-effectiveness. 相似文献
997.
Meihong Zhang Yuqian Fang Shuai Yuan Liyi Shi Zhuyi Wang Yi Wang Jiefang Zhu Yin Zhao 《Surface and interface analysis : SIA》2023,55(1):63-70
The graphitic carbon nitride (g-C3N4) materials with many intriguing properties have attracted much attention in photocatalysis. The photocatalytic activity of g-C3N4 is hindered by serious aggregation and limited exposed active sites. Herein is shown that nanosized g-C3N4 can be simply obtained by a superfast high-pressure homogenization approach. The high-pressure homogenization treatment can provide strong force to cut and/or to exfoliate the bulk g-C3N4 into nanosized g-C3N4 with good dispersion. Moreover, choosing different solvents during treatment can cause a different surface structure of as-prepared nanosized g-C3N4. In addition, the narrow bandgap properties, the high photogenerated charge carrier separation, and the transport abilities are achieved in as-prepared nanosized g-C3N4 because of the retaining conjugated C3N4 system. Specifically, the photocatalytic activities of as-prepared nanosized g-C3N4 have been significantly enhanced in terms of degradation of organic dye Rhodamine B (RhB) under visible light irradiation (10 times higher than that of bulk g-C3N4). These findings can provide a promising and simple approach to the exfoliation, nanonization, and surface functionalization of 2D layered materials. 相似文献
998.
以硝酸银、钛酸四丁酯、无水氯化锌、六水氯化铁为原料,采用溶胶-凝胶法与溶剂热相结合的方法制备了ZnFe2O4/Ag/TiO2复合材料,通过扫描电子显微镜、能谱分析仪、X射线粉末衍射仪、X射线光电子能谱仪、振动样品磁强计、紫外可见分光光度计对样品进行表征及测试。结果表明:ZnFe2O4/Ag/TiO2-10具有最佳的光催化效果,在紫外和可见光下对染料的降解率都能达到90%以上,具有优异的紫外可见光光催化活性。ZnFe2O4/Ag/TiO2具有独特的磁性,能在外部磁场作用下进行回收利用,这使其在实际应用中成为可能。通过磁分离技术重复回收利用5次后仍然保持优良的光催化性能,说明ZnFe2O4/Ag/TiO2-10具有优异的磁性及较高的光催化循环稳定性。 相似文献
999.
1000.
能源危机和环境问题已成为人类社会面临和亟待解决的两个重大问题。光催化技术被认为是解决能源危机和环境问题有效方法之一。来瓦希尔骨架材料(MILs)是一类著名的金属骨架有机材料(MOFs)。Fe-MILs是MILs系列材料中一个重要的分支,其带隙宽度约为2.39 eV ~ 2.79 eV,能被可见光激发。然而,Fe-MILs存在光的利用率低、导电性差、光生电子-空穴复合快、光腐蚀等缺点。近年来,研究者们采用多种方法对Fe-MILs进行改性,制备了很多Fe-MILs衍生的可见光响应复合材料,并将这些材料成功用于光诱导反应。本文主要综述了近年来Fe-MILs衍生的可见光响应复合材料在水的分解、CO2还原、有机物转化、光催化固氮等多个领域的应用研究,并对Fe-MILs光催化剂的发展提出了建议。 相似文献