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1.
Solar energy-driven photocatalytic water splitting has been investigated for decades to produce clean and renewable green hydrogen. In this paper, the cutting-edge research within the overall water splitting system is summarized from the one-step photocatalytic overall water splitting (POWS) system to the two-step system and the cocatalysts research in this field. In addition, the photocatalytic reaction engineering study is also reviewed which is crucial for future scale-up. This mini-review provides a picture of survey of recent progress of relevant overall water splitting system, with particular attention paid to material system and mechanistic breakthroughs, and highlights the challenge and opportunity of the current system.  相似文献   
2.
BaTi1−xFexO3 compositions (for x = 0, 0.1, and 0.2) were prepared via a solid-state reaction route. The presence of iron (Fe) in barium titanate (BaTiO3) eventually decreased the energy bandgap; thus, its utilization for water cleaning application through photocatalysis process was explored (using methylene blue [MB] dye as an indicative pollutant in water). Characterization of the synthesized powder was performed through scanning electron microscopy, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy. The bandgap of the synthesized powder was calculated as 3.2, 2.12, and 1.67 eV for BaTi1−xFexO3 compositions (for x = 0, 0.1, and 0.2), respectively. BaTi0.8Fe0.2O3 powder showed excellent results, and ∼71% of the MB dye (∼5 mg/L concentrated) was degraded using the photocatalysis process under visible light. To check the potentiality of BaTi1−xFexO3 compositions (for x = 0, 0.1, and 0.2), the photocatalysis process was carried out by changing the concentration of MB dye (2.5–10 mg/L with a step of 2.5 mg/L) and the amount of BaTi0.8Fe0.2O3 powder (0.05–0.2 g with a step of 0.05 g) for ∼5-mg/L concentrated MB dye. The treated water was further used as a growth parameter and phytotoxicity analysis through germination index on the wheat seeds. Lastly, the BaTi1−xFexO3 compositions (for x = 0, 0.1, and 0.2) were explored for water cleaning applications under real-time solar irradiation.  相似文献   
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张劢  田瑶  郭之旗  王叶  窦广进  宋浩 《化工学报》2022,73(7):2774-2789
光催化-生物杂合系统耦合了光催化对光能的高收集效率和广谱吸收性能,以及生物催化温和、高效且高特异性转化的优势,可实现多种高值化学品和燃料分子的绿色、可持续合成,符合“碳中和”发展大方向。按照生物催化载体的不同,光催化-生物杂合系统可分为:光催化-生物酶杂合系统和光催化-微生物杂合系统两大类。光催化-生物酶杂合系统根据作用机制细分为:辅因子介导的间接反应体系、直接电子传递的反应体系以及混合型光催化-生物酶杂合系统;光催化-微生物杂合系统分为:直接电子传递的胞外供能模式、化学物质介导的胞外供能模式以及胞内的能量供给模式。对这些模式的具体作用机制,以及存在的优缺点和关键问题做出了综合评述,并对该领域提出了未来展望。  相似文献   
5.
A glass hollow fiber membrane coated with TiO2 was successfully synthesized by dip-coating and calcination. In addition, the effects of the calcination temperature, number of coating layers, and treatment method on the photocatalytic removal of methylene blue from wastewater by the membrane were investigated. The results showed that the TiO2-coated membrane calcined at 550 °C was uniform. It showed good photocatalytic and anti-fouling properties. As compared to the basement membrane, the TiO2-coated membrane showed significantly improved photocatalytic removal of methylene blue. It showed a methylene blue removal degree as high as 97.2% and could be recycled multiple times by a simple treatment. The methylene blue removal degree of the membrane remained 92.3-93.6% after five recycling operations. Therefore, the membrane prepared via the simple method proposed in this study could be used as an efficient photocatalyst to remove methylene blue from wastewater.  相似文献   
6.
Z型异质结(Z Scheme heterojunctions)可将电子和空穴在不同半导体材料上实现空间分离,具有光谱响应宽、电荷分离效率高、氧化还原能力强、稳定性高等优势,在光催化CO2还原(CO2 reduction reaction,CO2RR)等应用中具有广阔前景,是未来光催化剂材料设计等领域的重点研究方向。综述了Z型异质结在光催化还原CO2领域的研究进展,具体阐述了液相、全固态和直接型三代Z型异质结的电荷转移机制,分别讨论了各类Z型异质结光催化体系的优缺点,并结合CO2RR原理总结了三类Z型异质结光催化剂在光催化CO2RR领域的应用现状。指出未来高性能Z型异质结光催化剂设计及光催化还原CO2研究应重点关注CO2还原产物(特别是C2及C2+产物)的生成机理,深入研究Z型异质结中电荷转移机理,重视还原产物溯源、提高实验设计与反应结果评价的严谨性,同时应面向大规模工业化应用开展系统性研究。  相似文献   
7.
《Ceramics International》2021,47(22):31073-31083
Pluronic 31R1 surfactant and MCM-41 silica were used to fabricate mesoporous Ag2O/g-C3N4 heterostructures with improved surface areas. The fabricated mesoporous nanocomposite was used to photo oxidize ciprofloxacin. The TEM images of Ag2O/g-C3N4 indicated a uniform dispersion of spherical approximately 4-nm Ag2O nanoparticles on g-C3N4. The mesoporous 0.9% Ag2O@g-C3N4 heterostructure exhibited 100% efficiency in ciprofloxacin oxidation within 60 min when compared with the 25% efficiency in 120 min of pure mesoporous Ag2O and 10% efficiency in 120 min of pure g-C3N4. The highest ciprofloxacin oxidation efficiency achieved was 100%, which was four and ten times better than those of Ag2O and g-C3N4, respectively. This superior performance of the mesoporous Ag2O/g-C3N4 was attributed to the high dispersion of nano-sized mesoporous Ag2O particles on the g-C3N4 surface, narrow bandgap, and significantly high surface areas. The powerful interaction between Ag2O and g-C3N4 ensured robust durability of Ag2O/g-C3N4 heterostructures, which is evident in the fact that five recycling trials of the photocatalyst rendered a minimal loss of efficiency.  相似文献   
8.
通过溶剂热法制备BiOCl纳米片,共沉淀法制备Ag_2CO_3和复合催化剂Ag_2CO_3/BiOCl,研究各材料可见光催化降解罗丹明B的效果,确定Ag_2CO_3与BiOCl的最佳配比,并通过表征分析复合材料的结构和异质结光催化降解机理。结果表明,当Ag_2CO_3与BiOCl的质量比为50%时,Ag_2CO_3/BiOCl异质结催化剂的可见光催化效率最高,其一级动力学反应速率常数是BiOCl和Ag_2CO_3的6.79和12.58倍。紫外可见漫反射分析证明,Ag_2CO_3的加入使Ag_2CO_3/BiOCl对可见光的吸收增加,拓宽了光响应范围。XPS价带谱证明,调控后的BiOCl纳米片能带位置上移。通过自由基捕获实验和电子顺磁共振(ESR)证明,其主要活性物种是·O~-_2、h~+和·OH,从而推断Ag_2CO_3与BiOCl构成Z型异质结,相比Ⅱ型异质结拥有较高的氧化还原能力,可充分利用水中的溶解氧(O_2)和OH~-,大大提升了光催化效率。  相似文献   
9.
A 0.5(Ba0.7Ca0.3)TiO3–0.5Ba(Zr0.1Ti0.9)O3 (BCT-BZT) ceramic was studied for photocatalysis and piezocatalysis effects using dye degradation (methylene blue, rhodamine B, and methyl orange) and bacterial (Escherichia coli) disinfection from aqueous solution. To examine the effect of ferroelectric polarization, BCT-BZT powder was poled using the corona poling technique. Same time, BCT-BZT was converted into Ag/BCT-BZT composites as Ag induced surface plasmon resonance effect during photocatalysis. Piezocatalysis performance was assessed for dyes mineralization under ultrasonication. There was a significant impact of silver nanoparticles on the photo/piezocatalysis performance of BCT-BZT. Similarly, electric poling has also played a positive role in improving the photo/piezocatalysis in view of various dye degradation. These samples also showed effective antibacterial performance.  相似文献   
10.
光催化剂在水泥基材料中的分散性问题一直是制约光催化水泥基材料性能的主要因素之一。本文通过在水泥基材料成型过程中加入铋系光催化前驱体溶液实现原位光催化水泥基材料的合成,提高光催化剂在水泥基体中的分散性,赋予水泥基材料光催化性能的同时改善水泥基体抗压强度。通过扫描电镜和EDS能谱对光催化水泥基材料微观结构和成分进行表征。结果表明,光催化水泥基材料对罗丹明B的降解效率最高可达91.64%,对氮氧化物的降解效率最高可达到15.03%,早期机械强度提升约10%。光催化剂在水泥基体中分散更加均匀,同时水泥基体致密度提高。本文揭示了原位光催化水泥基材料的光催化性能与机械性能的提升机制,为其他功能性水泥基材料的制备提供了理论基础。  相似文献   
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