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1.
 以太阳能光-化学转化中最为重要的反应-光催化分解水为核心,从光催化分解水的原理、半导体捕光材料、光生电荷分离策略、双助催化剂、Z机制分解水体系以及太阳能分解水制氢途径等方面,介绍了光催化分解水制氢的最新研究进展,并展望了其未来的发展趋势。  相似文献   

2.
无机层状化合物及其柱撑产物光解水制氢   总被引:6,自引:1,他引:6  
利用新型光催化剂实现太阳能分解水制氢是获得氢能的一种方便而廉价的方法,其关键是高效催化剂的获得.介绍了利用光催化技术催化分解水制氢的反应机理,综述了近年来有关层状钛酸盐、铌酸盐、钙钛矿型无机层状化合物及其柱撑产物在光解水制氢方面的研究进展,重点介绍了这些光催化材料的结构和光催化特性,并讨论了柱撑提高光催化活性的原理.  相似文献   

3.
基于可再生能源的分布式多目标供能系统(二)   总被引:7,自引:0,他引:7  
提出了两种以氢为能量载体的基于可再生能源的多目标分布式供能系统的新构思,分别利用太阳光直接分解水制氢及太阳能高温集热(或高温燃料电池排气余热)分解生物质和水制氢,并与高温燃料电池,微型燃气轮机以及后续的供热,制冷,调湿等子系统共同构成高效,无污染的可以供氢,供电,供热,供轴功的多联产综合供能系统,简要分析了可再生能源高效低成本制氢的有关理论与技术,报道了本室光催化分解水制氢与超临界水生物催化气化制氢研究的最新进展。  相似文献   

4.
太阳能光催化分解水制氢中的气泡动力学,涉及多物理场和光催化反应之间的相互作用,相比传统的沸腾换热和电解水领域气泡动力学更加复杂且具有独特性。本文从光催化分解水基本原理出发,综述了催化剂表面气泡成核生长动力学规律及其行为调控的研究进展。对于光催化分解水的气泡成核尺度和过饱和度,可以通过经典成核理论估算,然而受现有测试方式的制约,尚无法同时获取高空间和高时间分辨率的成核过程信息。对于催化剂表面气泡的生长规律,通常可由惯性控制、扩散控制和化学反应控制3种机制进行描述,而决定气泡生长控制机制的关键是有效反应表面与气泡尺寸的相对大小。为了有效降低气泡覆盖对光催化反应系统带来的负面影响,可通过添加表面活性剂、调节催化剂表面结构和润湿性为主的被动调控方式,以及施加外部流场、声场、磁场和周期性光照为主的主动调控方式,对气泡行为进行定向调控加以实现。当前研究面临的主要挑战是揭示光催化分解水过程中复杂物理场作用下的相间作用和能质输运机理,从而为未来低成本、高效利用太阳能光催化分解水制氢应用提供指导。  相似文献   

5.
光能取之不尽用之不竭,利用光催化技术分解水解制氢被认为是解决能源与环境问题的有效手段之一。2009年,氮化碳聚合物半导体实现了光催化产氧与产氢水分解半反应,打破了人们对有机聚合物半导体不宜作为光催化材料的传统认识。氮化碳材料由碳、氮两种元素构成,廉价易得,且光化学性质稳定。近年来,以氮化碳为代表的不含金属组分的光催化材料逐渐成为国际光催化研究的热点之一。本文将从氮化碳材料的光催化分解水的构-效关系出发,围绕共聚合氮化碳、结晶相氮化碳和氮化碳光电极,讨论氮化碳材料在光催化分解水的研究现状与发展趋势。  相似文献   

6.
太阳能作为一种取之不尽、用之不竭的清洁能源,将成为未来新能源的重要组成部分.目前人们除了利用太阳能光伏发电以外,还有利用仿生光合作用将太阳能转化为化学能、利用半导体光电极分解水制氢等方式.而在半导体材料中,低成本环保型的化合物半导体光伏材料(如Cu2ZnSnS4等)具有优良的光伏发电性能,同时也非常适合作为太阳光分解水制氢的材料.文章综述了近年来在Cu2ZnSnS4光伏电池及其太阳光分解水制氢领域的研究进展.  相似文献   

7.
氢是最清洁、最有前途的能量载体,可以通过光催化直接分解水来制备.TiO2由于活性高、稳定性好、无毒害等优点被广泛用于光催化分解水制氢.影响TiO2光催化活性的因素有TiO2的晶型、晶面、晶粒大小和形貌等,其中形貌对TiO2光催化活性的影响最大.调控形貌对TiO2的晶粒尺寸、晶面比例、比表面积、光的吸收、光生载流子的分离...  相似文献   

8.
综述了半导体光催化分解水制氢的基本原理以及近年来一些研究进展.对目前报导的光催化材料进行了整理和分类,评述了各种光催化材料的特点和性能;对光催化分解水的研究工作和发展方向进行了展望.  相似文献   

9.
金属-有机骨架(MOFs)材料UiO-66-NH_2用于光催化分解水制氢需要负载贵金属助催化剂,如Pt,但考虑贵金属价格昂贵,笔者以价格低廉的过渡金属Cu做产氢助催化剂,采用原位光沉积方法制备Cu/UiO-66-NH_2复合光催化材料.结果表明,沉积Cu可以促进UiO-66-NH_2的可见光光催化制氢性能.在优化的Cu担载量为6.0%(m/m),Cu/UiO-66-NH_2最高产氢速率为40μmol·h~(-1)·g~(-1),与负载1.0%-Pt/UiO-66-NH_2(m/m)材料的产氢速率相当.高光催化制氢性能归因于UiO-66-NH_2中光生电子可以向Cu助催化剂传输,从而提升电子-空穴对的分离.实验结果为过渡金属用作MOFs产氢助催化剂提供了实验基础.  相似文献   

10.
随着全球工业化的不断发展,化石燃料的消耗总量在不断攀升,随之带来的能源短缺与环境污染问题成为人们面临的重大挑战。氢能是一种绿色、低碳、高效的清洁能源,利用可持续再生的太阳能,通过光催化分解水制备氢气,被认为是解决上述问题的有效途径。金属有机框架具有结构可修饰、性能易调控、孔道结构丰富及比表面积较大的特性,被广泛应用于光催化领域。其中,Zr基MOFs结构类型丰富,同时具备优异的热稳定性、化学稳定性和机械稳定性,被广大研究人员所青睐。总结了近10年来Zr基配合物光催化分解水制氢的相关研究工作,从扩大可见光吸收范围、提升光生电子和空穴分离效率2个方面阐述了高效Zr基配合物光催化剂的设计思路,为光催化领域更多科研工作者开展相关工作提供了理论支撑。  相似文献   

11.
 利用太阳光分解水制备氢气,从太阳照射能量中直接获得大功率的动力能源,被认为是人类能源的终极梦想.本文介绍了太阳光催化分解水制氢的原理,阐述了光解水对光催化材料的热力学和动力学要求.重点从新型光催化材料研发、共催化复合体系构筑、纳米形貌调控、器件化设计等4个方面综述了近年来国内外光解水制氢关键材料和技术的研究进展.结合实际应用,对制氢体系中牺牲剂应用、模拟自然光合作用、光解海水、光催化剂稳定性等方面的研究进行了分析.展望了未来太阳光催化分解水制氢技术的发展方向.  相似文献   

12.
An ever growing demand for energy coupled with increasing pollution is forcing us to seek environmentally clean alternative energy resources to substitute fossil fuels. The rapid development of nanomaterials has opened up new avenues for the conversion and utilization of renewable energy. This article reviews nanostructured materials designed for selected applications in renewable energy conversion and utilization. The review is based on the authors’ research, with particular focus on solar hydrogen production, hydrogen storage and hydrogen utilization. The topics include photoelectrochemical (PEC) water splitting and photocatalytic hydrogen production, solid-state hydrogen storage, and proton exchange membrane fuel cells (PEMFCs). It is expected that the rational design of nanomaterials could play an important role in achieving a renewable energy based economy in the coming decades.  相似文献   

13.
Z Zou  J Ye  K Sayama  H Arakawa 《Nature》2001,414(6864):625-627
The photocatalytic splitting of water into hydrogen and oxygen using solar energy is a potentially clean and renewable source for hydrogen fuel. The first photocatalysts suitable for water splitting, or for activating hydrogen production from carbohydrate compounds made by plants from water and carbon dioxide, were developed several decades ago. But these catalysts operate with ultraviolet light, which accounts for only 4% of the incoming solar energy and thus renders the overall process impractical. For this reason, considerable efforts have been invested in developing photocatalysts capable of using the less energetic but more abundant visible light, which accounts for about 43% of the incoming solar energy. However, systems that are sufficiently stable and efficient for practical use have not yet been realized. Here we show that doping of indium-tantalum-oxide with nickel yields a series of photocatalysts, In(1-x)Ni(x)TaO(4) (x = 0-0.2), which induces direct splitting of water into stoichiometric amounts of oxygen and hydrogen under visible light irradiation with a quantum yield of about 0.66%. Our findings suggest that the use of solar energy for photocatalytic water splitting might provide a viable source for 'clean' hydrogen fuel, once the catalytic efficiency of the semiconductor system has been improved by increasing its surface area and suitable modifications of the surface sites.  相似文献   

14.
沉淀法制备的硫化镉经不同温度煅烧处理获得不同相的硫化镉光催化剂,采用X射线衍射、紫外-可见漫反射光谱表征催化剂的结构和性质.以制备的硫化镉粉体作为光催化剂,在存在空穴牺牲剂的条件下进行光解水制氢实验,研究了硫化镉晶体的相组成、牺牲剂种类和助催化剂的担载量对其光解水活性的影响.结果表明,400℃下焙烧的硫化镉具有最好的催化活性,乳酸作为牺牲剂更有利于硫化镉光解水制氢,助催化剂(铂)的担载量为0.1%时,硫化镉具有最高的光催化活性.  相似文献   

15.
 介绍了光电催化(PEC)分解水和还原CO2的基本原理、研究进展。探讨了提高PEC效率的关键策略,主要包括通过能带调控、形貌控制和敏化提高光吸收,通过助催化剂促进表面反应,以及通过构建局部偶极或异质电场、形貌调控和界面修饰促进电荷分离与传输等。  相似文献   

16.
Photoelectrochemical (PEC) water splitting for solar energy conversion into chemical fuels has attracted intense research attention.The semiconductor hematite (...  相似文献   

17.
 介绍了光电催化(PEC)分解水和还原CO2的基本原理、研究进展。探讨了提高PEC效率的关键策略,主要包括通过能带调控、形貌控制和敏化提高光吸收,通过助催化剂促进表面反应,以及通过构建局部偶极或异质电场、形貌调控和界面修饰促进电荷分离与传输等。  相似文献   

18.
Searching for visible-infrared solar utilization for photocatalytic water splitting is highly desirable,since most of solar energy is distributed the visible-infrared region.However,it is difficult for a pure system to satisfy both band gap and band edge conditions for water splitting in visible-infrared region.Herein,heterostructure consisting of Janus MoSSe and nitrides XN (X=Al,Ga) is proposed,and the structural and electronic properties are systematically studied by the firstprinciples calculations.It shows that the AA-stacking heterostructure is more stable than other stacking.The calculated electronic property shows that MoSSe/AIN heterostructures have indirect band gaps in the range of 1.00eV-1.68eV,while MoSSe/GaN heterostructures are always direct semiconductors with band gaps of0.8 eV-1.51 eV.Interestingly,despite the band gaps of MoSSe/XN heterostructures being smaller than 1.23 eV,the band edge positions are always suitable for water splitting,suggesting good activity of these heterostructures in visible-infrared region.This special behavior mainly originates from the intrinsic dipole with the electrons of VBM and CBM distributed on two opposite layers,producing an electrostatic potential difference between the layers.This electrostatic potential difference,acting as an auxiliary booster for photoinduced carriers,can effectively reduce the band gap required for water splitting in visible-infrared region.In addition,the band edge position can be further adjusted by strains,leading to higher reactivity for water splitting.Our findings strongly suggest that this novel Janus MoSSe/XN heterostructure can offer exciting opportunities for designing visible-infrared photocatalysis for water splitting.  相似文献   

19.
Climate change and the consumption of non-renewable resources are considered as the greatest problems facing humankind.Because of this,photocatalysis research has been rapidly expanding.TiO2 nanoparticles have been extensively investigated for photocatalytic applications including the decomposition of organic compounds and production of H2 as a fuel using solar energy. This article reviews the structure and electronic properties of TiO2,compares TiO2 with other common semiconductors used for photocatalytic applications and clarifies the advantages of using TiO2 nanoparticles.TiO2 is considered close to an ideal semi- conductor for photocatalysis but possesses certain limitations such as poor absorption of visible radiation and rapid recombination of photogenerated electron/hole pairs.In this review article,various methods used to enhance the photocatalytic characteristics of TiO2 including dye sensitization,doping,coupling and capping are discussed.Environmental and energy applications of TiO2, including photocatalytic treatment of wastewater,pesticide degradation and water splitting to produce hydrogen have been summarized.  相似文献   

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