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1.
近年来,钙钛矿型化合物以其特有的结构在光催化领域成为国内外研究的热点。钛酸锶(SrTiO3)是一种典型的钙钛矿型复合氧化物,具有稳定性高、无毒性,载流子迁移率高,光催化活性高等特点,作为半导体有低阻的电子运输结构和对小分子高效的氧化还原能力,是一种极具开发潜力和应用前景的光催化材料。主要介绍了SrTiO3材料的结构、制备方法与光催化机理,并对近年来SrTiO3在光催化领域的改性研究进行综述。最后在现有研究成果的基础上,对SrTiO3光催化材料的未来发展动向进行简要分析,有助于研究者取得进一步突破。  相似文献   

2.
As a sustainable technology, semiconductor photocatalysis has attracted considerable interest in the past several decades owing to the potential to relieve or resolve energy and environmental‐pollution issues. By virtue of their unique structural and electronic properties, emerging ultrathin 2D materials with appropriate band structure show enormous potential to achieve efficient photocatalytic performance. Here, the state‐of‐the‐art progress on ultrathin 2D photocatalysts is reviewed and a critical appraisal of the classification, controllable synthesis, and formation mechanism of ultrathin 2D photocatalysts is presented. Then, different strategies to tailor the electronic structure of ultrathin 2D photocatalysts are summarized, including component tuning, thickness tuning, doping, and defect engineering. Hybridization with the introduction of a foreign component and maintaining the ultrathin 2D structure is presented to further boost the photocatalytic performance, such as quantum dots/2D materials, single atoms/2D materials, molecular/2D materials, and 2D–2D stacking materials. More importantly, the advancement of versatile photocatalytic applications of ultrathin 2D photocatalysts in the fields of water oxidation, hydrogen evolution, CO2 reduction, nitrogen fixation, organic syntheses, and removal pollutants is discussed. Finally, the future opportunities and challenges regarding ultrathin 2D photocatalysts to bring about new opportunities for future research in the field of photocatalysis are also presented.  相似文献   

3.
In recent years, three-dimensionally ordered macroporous (3DOM) materials have attracted tremendous interest in the field of photocatalysis due to the periodic spatial structure and unique physicochemical properties of 3DOM catalysts. In this review, the fundamentals and principles of 3DOM photocatalysts are briefly introduced, including the overview of 3DOM materials, the photocatalytic principles based on 3DOM materials, and the advantages of 3DOM materials in photocatalysis. The preparation methods of 3DOM materials are also presented. The structure and properties of 3DOM materials and their effects on photocatalytic performance are briefly summarized. More importantly, 3DOM materials, as a supported catalyst, are extensively employed to combine with various common materials, including metal nanoparticles, metal oxides, metal sulfides, and carbon materials, to enhance photocatalytic performance. Finally, the prospects and challenges for the development of 3DOM materials in the field of photocatalysis are presented.  相似文献   

4.
《工程(英文)》2021,7(7):991-1001
Semiconductor photocatalysis is a potential pathway to solve the problems of global energy shortage and environmental pollution. Black phosphorus (BP) has been widely used in the field of photocatalysis owing to its features of high hole mobility, adjustable bandgap, and wide optical absorption range. Nevertheless, pristine BP still exhibits unsatisfactory photocatalytic activity due to the low separation efficiency of photoinduced charge carriers. In recent years, the construction of heterostructured photocatalysts based on BP has become a research hotspot in photocatalysis with the remarkable improvement of photoexcited charge-separation efficiency. Herein, progress on the design, synthesis, properties, and applications of BP and its corresponding heterostructured photocatalysts is summarized. Furthermore, the photocatalytic applications of BP-based heterostructured photocatalysts in water splitting, pollutant degradation, carbon dioxide reduction, nitrogen fixation, bacterial disinfection, and organic synthesis are reviewed. Opportunities and challenges for the exploration of advanced BP-based heterostructured photocatalysts are presented. This review will promote the development and applications of BP-based heterostructured photocatalysts in energy conversion and environmental remediation.  相似文献   

5.
The increasing application of exposed high energy facet is an effective strategy to improve the photocatalytic performance of photocatalysts because the vacancies are beneficial to photocatalytic reaction. Vacancy dominates numerous distinct properties of semiconductor materials and thus plays a conclusive role in the photocatalysis applications. In this work, two kinds of BiOI nanomaterials with different vacancies are synthesized via a facile solvothermal method. The positron annihilation analysis shows that the thinner BiOI nanosheets possess larger‐sized vacancy than BiOI nanoplates. Thus, BiOI nanosheets show the enhanced separation efficiency of electron–hole pairs and adsorption ability for contaminants under visible light. The results are also validated with the first‐principle computation. Therefore, higher photocatalytic activity to the photodegradation of tetracycline is observed from the nanosheets than that obtained from BiOI nanoplates. This work not only arouses attention to vacancies, but also opens up an avenue for precision design of vacancies to prepare novel photocatalytic materials driven under solar light.  相似文献   

6.
《工程(英文)》2017,3(3):365-378
Photocatalytic water splitting, which directly converts solar energy into hydrogen, is one of the most desirable solar-energy-conversion approaches. The ultimate target of photocatalysis is to explore efficient and stable photocatalysts for solar water splitting. Tantalum (oxy)nitride-based materials are a class of the most promising photocatalysts for solar water splitting because of their narrow bandgaps and sufficient band energy potentials for water splitting. Tantalum (oxy)nitride-based photocatalysts have experienced intensive exploration, and encouraging progress has been achieved over the past years. However, the solar-to-hydrogen (STH) conversion efficiency is still very far from its theoretical value. The question of how to better design these materials in order to further improve their water-splitting capability is of interest and importance. This review summarizes the development of tantalum (oxy)nitride-based photocatalysts for solar water spitting. Special interest is paid to important strategies for improving photocatalytic water-splitting efficiency. This paper also proposes future trends to explore in the research area of tantalum-based narrow bandgap photocatalysts for solar water splitting.  相似文献   

7.
Highly active photocatalysts driving chemical reactions are of paramount importance toward renewable energy substitutes and environmental protection. As a fascinating Aurivillius phase material, Bi2MoO6 has been the hotspot in photocatalytic applications due to its visible light absorption, nontoxicity, low cost, and high chemical durability. However, pure Bi2MoO6 suffers from low efficiency in separating photogenerated carriers, small surface area, and poor quantum yield, resulting in low photocatalytic activity. Various strategies, such as morphology control, doping/defect‐introduction, metal deposition, semiconductor combination, and surface modification with conjugative π structures, have been systematically explored to improve the photocatalytic activity of Bi2MoO6. To accelerate further developments of Bi2MoO6 in the field of photocatalysis, this comprehensive Review endeavors to summarize recent research progress for the construction of highly efficient Bi2MoO6‐based photocatalysts. Furthermore, benefiting from the enhanced photocatalytic activity of Bi2MoO6‐based materials, various photocatalytic applications including water splitting, pollutant removal, and disinfection of bacteria, were introduced and critically reviewed. Finally, the current challenges and prospects of Bi2MoO6 are pointed out. This comprehensive Review is expected to consolidate the existing fundamental theories of photocatalysis and pave a novel avenue to rationally design highly efficient Bi2MoO6‐based photocatalysts for environmental pollution control and green energy development.  相似文献   

8.
光催化技术是解决当今人类社会中环境问题和能源危机两大问题的有效途径,半导体材料在早期的研究中备受青睐。然而,单一半导体光催化剂存在可见光响应程度差、电子空穴对易复合等缺点,光催化技术在降解染料废水的应用中有效率较低,因此研究者对新型复合纳米材料作为光催化剂降解染料废水进行了深入的研究。本文介绍了石墨烯、金属有机骨架、碳量子点三种新型复合纳米材料用于光催化降解染料废水中污染物的研究进展和主要研究结果,按照复合纳米材料设计升级的思路,简述了部分新型复合纳米材料的制备方法,对目标污染物的降解率进行了分析。通过总结新型光催化材料降解水中污染物的性能,对未来发展趋势进行了展望,指出新型复合纳米材料在光催化方向今后的发展趋势和研究重点是有针对性的处理废水,并实现工业化。  相似文献   

9.
黄飞  蒲雪超  冉濛  梁琦  赵辉  齐敏  闫爱华 《材料导报》2016,30(15):12-18
二硫化钼(MoS_2)具有类石墨烯层状结构、良好的光学性能和电子传输特性,在光催化、太阳能电池、光开关等领域具有广阔的应用前景,一直备受关注。综述了近5年MoS_2纳米材料在光催化降解有机物和光催化水解制氢领域内的最新研究进展,分析了MoS_2纳米材料在光催化应用中存在的主要问题与挑战,重点介绍了相关解决方法。最后展望了MoS_2纳米材料在光催化应用中的发展方向和应用前景。  相似文献   

10.
气、光敏材料ZnO的掺杂改性研究   总被引:7,自引:0,他引:7  
综述了多功能材料ZnO的气敏和光催化机理,分别介绍了为了改进ZnO的气敏性能和光催化性能而进行的掺杂改性措施,包括掺杂贵金属、普通金属离子、金属氧化物等,提出综合利用ZnO的气、光敏特性,选择合适的掺杂剂对ZnO进行修饰改性将是提高ZnO气敏元件性能的一个较好的方向.  相似文献   

11.
溶胶—凝胶法制备TiO2/Pt/glass纳米薄膜及其光电催化性能   总被引:14,自引:0,他引:14  
符小荣  张校刚 《功能材料》1997,28(4):411-414
本文采用Sol-gel法制备了TiO2/Pt/glass纳米光催化薄膜,并进行了结构和乐电催化性能的测试。薄膜对染料溶液的光电催化降解结果表明,当输入正向偏压后,TiO2/Pt/glass薄膜的光催化性能有一定提高,且随着偏压增大而增强。同时,薄膜的中间层Pt及光源强度对薄膜的光电催化活性也有较大影响。  相似文献   

12.
Graphitic carbon nitride (g-C3 N4) with the merits of high visible light absorption,proper electronic band structure with high conduction band edge and variable modulation,is viewed as a promising photocatalyst for practical use.To alleviate its high recombination rate of photo-excited charge carriers and maximize the photocatalytic performances,it is paramount to design highly effective transfer channels for photo-excited charge carriers.Ferroelectric materials can have the charge carriers transport in opposite directions owing to the internal spontaneous polarization,which may be suitable for constructing the heterostructure with g-C3N4 for efficient charge separation.Inspired by this concept,herein ferroelec tric PbTiO3,which can be the visible-light absorber,is coupled with g-C3N4 to construct PbTiO3/g-C3N4 heterostructure with close contact via Pb-N bond by the facile post thermal treatment.The optimized PbTiO3/g-C3N4 heterostructure exhibited excellent photocatalytic and photoelectrochemical activities under visible light irradiation.Moreover,the simultaneous application of ultrasound-induced mechanical waves can further improve its photocatalytic activities through reinforcing the built-in piezoelectric field.This work proposes a widely applicable strategy for the fabrication of high-performance ferroelectric based photocatalysts and also provides some new ideas for developing the understanding of ferroelectric photocatalysis.  相似文献   

13.
邢阳阳  李秋叶  杨建军 《功能材料》2012,43(16):2126-2130
Ag-基等离子体共振光催化剂因其特殊的物理化学性能,在光催化降解污染物、分解水和生物传感器等方面受到了广泛关注。尤其是Ag/AgX(X=Cl、Br、I)类等离子体光催化剂,由于其在可见光催化降解有机污染物中的优异表现,成为近年来可见光催化领域的研究热点。综述了近年来Ag-基等离子体共振光催化剂的研究进展,并深入探讨了其光催化反应机理。Ag-基等离子体共振光催化剂合成方法简单易行,原料成本低,光催化效率高,必将在应用光催化领域具有良好的发展前景。  相似文献   

14.
TiO2纳米管由于具有较大的比表面积、优异的光催化活性以及结构可控的特性,使其在电学、光学、催化剂以及传感器、锂离子电池、染料敏化太阳能电池、能源转换等方面具有非常大的应用潜力。目前采用简单的水热法就能够在较低的温度和压力下制备出二氧化钛纳米管,这使得水热法合成TiO2纳米管受到广泛关注。文章主要综述了水热法制备TiO2纳米管的形成机理以及温度、原料、酸洗、干燥、填充度等因素对纳米管形成的影响。  相似文献   

15.
Photocatalysis driven by solar energy is a feasible strategy to alleviate energy crises and environmental problems. In recent years, significant progress has been made in developing advanced photocatalysts for efficient solar-to-chemical energy conversion. Single-atom catalysts have the advantages of highly dispersed active sites, maximum atomic utilization, unique coordination environment, and electronic structure, which have become a research hotspot in heterogeneous photocatalysis. This paper introduces the potential supports, preparation, and characterization methods of single-atom photocatalysts in detail. Subsequently, the fascinating effects of single-atom photocatalysts on three critical steps of photocatalysis (the absorption of incident light to produce electron-hole pairs, carrier separation and migration, and interface reactions) are analyzed. At the same time, the applications of single-atom photocatalysts in energy conversion and environmental protection (CO2 reduction, water splitting, N2 fixation, organic macromolecule reforming, air pollutant removal, and water pollutant degradation) are systematically summarized. Finally, the opportunities and challenges of single-atom catalysts in heterogeneous photocatalysis are discussed. It is hoped that this work can provide insights into the design, synthesis, and application of single-atom photocatalysts and promote the development of high-performance photocatalytic systems.  相似文献   

16.
Visible light photocatalysis is a promising route for harnessing of solar energy to perform useful chemical reactions and to convert light to chemical energy. Nanoscale photocatalytic systems used to date were based mostly on oxide semiconductors aided by metal deposition and were operational only under UV illumination. Additionally, the degree of control over particle size and shape was limited. We report visible light photocatalysis using highly controlled hybrid gold-tipped CdSe nanorods (nanodumbbells). Under visible light irradiation, charge separation takes place between the semiconductor and metal parts of the hybrid particles. The charge-separated state was then utilized for direct photoreduction of a model acceptor molecule, methylene blue, or alternatively, retained for later use to perform the reduction reaction in the dark.  相似文献   

17.
以Ti(SO4)2、Al2(SO4)3·18H2O为原料,采用乙醇助水热法制备了Al2O3-TiO2复合光催化剂,并通过改变A1/Ti物质的量之比、乙醇的体积分数、水热反应温度和反应时间等得到材料制备的最佳条件。XRD分析表明样品中的TiO2以锐钛矿晶相存在,SEM显示样品粒径范围在30-50nm之间。用最佳条件制备的复合光催化剂降解甲基橙溶液,反应30min后降解率这91%,降解过程符合一级动力学方程。  相似文献   

18.
作为一种新型的环境净化技术, 半导体光催化技术已引起全世界范围的广泛关注。然而, 传统光催化剂对太阳能利用率低、且光生电子-空穴对易于复合, 极大限制了该技术的实际应用。因此, 通过不同的改性手段合成具有可见光响应活性的光催化材料成为光催化领域研究的热点课题。提高光催化剂的活性, 除了合成方法的优选(调控尺寸、形貌、结晶度、微结构)外, 改性也是提高催化剂活性的主要手段。本文从半导体光催化的基本原理出发, 概述了半导体光催化剂改性的基本思想: 即拓宽太阳光利用范围和提高光生电子-空穴的寿命。围绕这一思想, 常用的改性策略有化学结构调控(能带调控), 以拓宽光谱响应范围; 表面修饰(表面敏化、半导体耦合和贵金属沉积)以提高电荷的分离效率。合适的能带结构是拓展催化剂的可见光响应范围和提高电荷分离效率的关键。  相似文献   

19.
Covalent organic frameworks (COFs), connecting different organic units into one system through covalent bonds, are crystalline organic porous materials with 2D or 3D networks. Compared with conventional porous materials such as inorganic zeolite, active carbon, and metal‐organic frameworks, COFs are a new type of porous materials with well‐designed pore structure, high surface area, outstanding stability, and easy functionalization at the molecular level, which have attracted extensive attention in various fields, such as energy storage, gas separation, sensing, photoluminescence, proton conduction, magnetic properties, drug delivery, and heterogeneous catalysis. Herein, the recent advances in metal‐free COFs as a versatile platform for heterogeneous catalysis in a wide range of chemical reactions are presented and the synthetic strategy and promising catalytic applications of COF‐based catalysts (including photocatalysis) are summarized. According to the types of catalytic reactions, this review is divided into the following five parts for discussion: achiral organic catalysis, chiral organic conversion, photocatalytic organic reactions, photocatalytic energy conversion (including water splitting and the reduction of carbon dioxide), and photocatalytic pollutant degradation. Furthermore, the remaining challenges and prospects of COFs as heterogeneous catalysts are also presented.  相似文献   

20.
Heterogeneous UV-photocatalytic process has been studied as tertiary treatment of real municipal wastewater. Wastewater photocatalytic treatment was carried out using several materials previously developed as photocatalysts: volcanic ashes and nanostructured titania supported over volcanic ashes. Both material activities in particles were compared with Degussa TiO2 (powder). Photocatalyst amount influence was studied by varying it between 2 and 10 g L?1. Wastewater decontamination process was evaluated measuring the chemical oxygen demand evolution with phototreatment time in order to choose the best photocatalytic material and its optimal operation concentration. Moreover, the photocatalytic results obtained were compared with those obtained from photolysis and adsorption studies in wastewater using the same operation conditions. In addition, analyses of main wastewater parameters were made in order to evaluate the complete water decontamination process. Possibility of using photocatalysts in particles shows the main advantage of continuous photocatalyst separation from the water effluent once the decontamination process has finished. Good photocatalytic activities were observed, and it allows to conclude that heterogeneous photocatalysis is an effective method for municipal wastewater treatment, achieving water disinfection and phosphates removal.  相似文献   

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