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Cu/TiO_(2) Photocatalysts for CO_(2) Reduction: Structure and Evolution of the Cocatalyst Active Form
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作者 Andrey A.Saraev Anna Yu.Kurenkova +3 位作者 Denis D.Mishchenko Alexandr L.Trigub Evgeniy Yu.Gerasimov Ekaterina A.Kozlova 《Transactions of Tianjin University》 EI CAS 2024年第2期140-151,共12页
Extensive work on a Cu-modified TiO_(2) photocatalyst for CO_(2) reduction under visible light irradiation was conducted. The structure of the copper cocatalyst was established using UV-vis diff use refl ectance spect... Extensive work on a Cu-modified TiO_(2) photocatalyst for CO_(2) reduction under visible light irradiation was conducted. The structure of the copper cocatalyst was established using UV-vis diff use refl ectance spectroscopy, high-resolution transmis- sion electron microscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. It was found that copper exists in different states (Cu 0 , Cu^(+) , and Cu^(2+) ), the content of which depends on the TiO_(2) calcination temperature and copper loading. The optimum composition of the cocatalyst has a photocatalyst based on TiO_(2) calcined at 700℃ and modified with 5 wt% copper, the activity of which is 22 μmol/(h·g cat ) (409 nm). Analysis of the photocatalysts after the photocatalytic reaction disclosed that the copper metal on the surface of the calcined TiO_(2) was gradually converted into Cu_(2) O during the photocatalytic reaction. Meanwhile, the metallic copper on the surface of the noncalcined TiO_(2) did not undergo any trans- formation during the reaction. 展开更多
关键词 PHOTOCATALYSIS Photocatalytic CO_(2)conversion Visible light Titanium dioxide Copper Copper oxides Methane formation photocatalyst transformation
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TiO2-PES Fibrous Composite Material for Ammonia Removal Using UV-A Photocatalyst
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作者 Anh Phuong Le Thi Masaru Ohshiro Takaomi Kobayashi 《Journal of Materials Science and Chemical Engineering》 2024年第1期1-19,共19页
This study focused on the development and characterization of TiO<sub>2</sub>-PES composite fibers with varying TiO<sub>2</sub> loading amounts using a phase inversion process. The resulting co... This study focused on the development and characterization of TiO<sub>2</sub>-PES composite fibers with varying TiO<sub>2</sub> loading amounts using a phase inversion process. The resulting composite fibers exhibited a sponge-like structure with embedded TiO<sub>2</sub> nanoparticles within a polymer matrix. Their photocatalytic performance for ammonia removal from aqueous solutions under UV-A light exposure was thoroughly investigated. The findings revealed that PeTi8 composite fibers displayed superior adsorption capacity compared to other samples. Moreover, the study explored the impact of pH, light intensity, and catalyst dosage on the photocatalytic degradation of ammonia. Adsorption equilibrium isotherms closely followed the Langmuir model, with the results indicating a correlation between qm values of 2.49 mg/g and the porous structure of the adsorbents. The research underscored the efficacy of TiO<sub>2</sub> composite fibers in the photocatalytic removal of aqueous under  UV-A light. Notably, increasing the distance between the photocatalyst and the light source resulted in de-creased hydroxyl radical concentration, influencing photocatalytic efficiency. These findings contribute to our understanding of TiO<sub>2</sub> composite fibers as promising photocatalysts for ammonia removal in water treatment applications. 展开更多
关键词 Ammonia Removal photocatalyst TiO2-PES Composite Fiber Fibrous Material
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MoS_(2)/ZnO异质结纳米材料降解亚甲基蓝的光催化性能研究 被引量:1
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作者 王进美 蒋守杰 +2 位作者 王春霞 王丽丽 高大伟 《西安工程大学学报》 CAS 2024年第1期24-30,共7页
为了提高ZnO的光转换效率,选用带隙较低的MoS_(2)形成异质结提高ZnO的光催化性能。通过水热法制备ZnO纳米棒,并进一步制备MoS_(2)/ZnO异质结构的纳米复合材料。通过扫描电镜(SEM)、X射线粉末衍射仪(XRD)、固体紫外可见漫反射测试仪(UV-V... 为了提高ZnO的光转换效率,选用带隙较低的MoS_(2)形成异质结提高ZnO的光催化性能。通过水热法制备ZnO纳米棒,并进一步制备MoS_(2)/ZnO异质结构的纳米复合材料。通过扫描电镜(SEM)、X射线粉末衍射仪(XRD)、固体紫外可见漫反射测试仪(UV-Vis)和紫外可见分光光度计(UV-245)等分析方法对样品的形貌、结构及光学性能等进行表征。结果表明,MoS_(2)/ZnO异质结复合材料呈棒状结构,并由于内建电场存在可有效增强光生载流子的分离效率,进而提高了可见光区的吸收,提高了光催化性能。在模拟太阳光(包含紫外波段)下,60 min时MoS_(2)-15/ZnO纳米复合材料对亚甲基蓝的降解率可达99%,比纯ZnO的降解率提高了10%。 展开更多
关键词 MoS_(2)/ZnO 光催化 异质结 亚甲基蓝 纳米复合材料
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Z型异质结Cu_(2)O/Bi_(2)MoO_(6)的构建及光催化降解性能
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作者 赵强 郭智楠 +5 位作者 李淑英 王俊丽 李作鹏 贾治芳 王科伟 郭永 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第5期885-894,共10页
通过水热法制备出一系列Z型异质结Cu_(2)O/Bi_(2)MoO_(6)新型光催化剂。采用扫描电子显微镜、粉末X射线衍射、红外光谱、紫外可见吸收光谱等表征手段研究了催化剂的形貌、结构性质和光电化学性质,并以四环素(TC)为降解目标污染物,进一... 通过水热法制备出一系列Z型异质结Cu_(2)O/Bi_(2)MoO_(6)新型光催化剂。采用扫描电子显微镜、粉末X射线衍射、红外光谱、紫外可见吸收光谱等表征手段研究了催化剂的形貌、结构性质和光电化学性质,并以四环素(TC)为降解目标污染物,进一步探究了其催化效率。实验结果表明,Cu_(2)O的加入提高了复合催化剂的光催化性能,其中20%Cu_(2)O/Bi_(2)MoO_(6)复合催化剂(Cu_(2)O和Bi_(2)MoO_(6)的质量比为20%)降解效果最好,100 min内可降解95%的TC。Cu_(2)O与Bi_(2)MoO_(6)之间的协同作用使其可以吸收更多的可见光,所构建的Z型异质结改变了电子转移途径,提高了电子与空穴的分离效率,光催化活性显著提高。通过自由基捕获实验和能带结构,分析了Z型异质结Cu_(2)O/Bi_(2)MoO_(6)复合催化剂光催化降解TC可能的机理。 展开更多
关键词 光催化剂 钼酸铋 氧化亚铜 Cu_(2)O/Bi_(2)MoO_(6) Z型异质结 四环素
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水热反应温度对ZnIn_(2)S_(4)/Bi_(2)WO_(6)复合催化剂的影响研究
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作者 王震 刘婷婷 +1 位作者 张强 王磊 《功能材料》 CAS CSCD 北大核心 2024年第7期7191-7199,共9页
为解决传统半导体光催化剂可见光响应能力弱、光生电子空穴复合快、能带结构导致载流子氧化还原能力弱等问题,采用水热法制备ZnIn_(2)S_(4)/Bi_(2)WO_(6)(ZlS@BW)复合催化剂并系统研究水热反应温度对其结构性能的影响。当水热温度从80... 为解决传统半导体光催化剂可见光响应能力弱、光生电子空穴复合快、能带结构导致载流子氧化还原能力弱等问题,采用水热法制备ZnIn_(2)S_(4)/Bi_(2)WO_(6)(ZlS@BW)复合催化剂并系统研究水热反应温度对其结构性能的影响。当水热温度从80℃升高到160℃,ZlS@BW复合光催化剂结晶度提高,形貌转变为致密核壳结构,比表面积和光电性能先降低再升高,氟伐他汀去除率逐步上升。而当温度升高到200℃时,核壳结构遭到了破坏,比表面积和光电性能变差,氟伐他汀的降解效果降低,光催化性能下降。结果表明,水热温度为160℃时,制备的ZlS@BW复合光催化剂晶型结晶程度较高,且形貌致密,比表面积最大,产生的瞬态光电流最大,阻抗半径最小,具有最优光催化性能。对污染物氟伐他汀降的降解效率最高,可达到75.47%。 展开更多
关键词 水热法 水热反应温度 ZnIn_(2)S_(4)/Bi_(2)WO_(6)复合催化剂 光催化
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TiO_(2)基光催化剂的负载改性方法研究进展 被引量:1
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作者 刘贺津 乔鹏 +1 位作者 朴锐 王雪芹 《当代化工》 CAS 2024年第4期953-956,996,共5页
TiO_(2)由于比表面积大、化学性质稳定、具有较高光催化活性等优点,在环境治理保护、光催化降解污染物等方面广泛应用。但其禁带宽度较大,只能吸收紫外光,且光生电子-空穴对再复合率较高,使其对太阳光的利用率大大降低,从而限制了其大... TiO_(2)由于比表面积大、化学性质稳定、具有较高光催化活性等优点,在环境治理保护、光催化降解污染物等方面广泛应用。但其禁带宽度较大,只能吸收紫外光,且光生电子-空穴对再复合率较高,使其对太阳光的利用率大大降低,从而限制了其大规模的工业化应用。因此,如何进一步提高TiO_(2)半导体材料的光催化效果以及对太阳光的利用率备受研究者关注。对TiO_(2)的负载改性方法如非金属元素负载、金属元素负载、半导体复合改性以及染料敏化改性等方面的研究进展进行了综述。 展开更多
关键词 TiO_(2)光催化剂 金属元素负载改性 非金属元素负载改性 半导体复合改性
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稀土La掺杂TiO_(2)纳米纤维高响应光催化降解染料研究
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作者 葛烨倩 徐佳琦 +3 位作者 曹琪 张霞霞 王益峰 许福军 《功能材料》 CAS CSCD 北大核心 2024年第3期3159-3164,共6页
为了提高TiO_(2)光催化性能,并研究金属离子掺杂对TiO_(2)光催化性能的影响,采用静电纺丝技术和煅烧工艺制备稀土元素La掺杂TiO_(2)无机纳米纤维膜,通过SEM、XRD、FT-IR、TG测试对材料的形貌、结构进行表征,以亚甲基蓝为靶向降解剂,进... 为了提高TiO_(2)光催化性能,并研究金属离子掺杂对TiO_(2)光催化性能的影响,采用静电纺丝技术和煅烧工艺制备稀土元素La掺杂TiO_(2)无机纳米纤维膜,通过SEM、XRD、FT-IR、TG测试对材料的形貌、结构进行表征,以亚甲基蓝为靶向降解剂,进一步深入研究La^(3+)改性TiO_(2)光催化氧化降解染料的机理。结果表明,当染料浓度为10 mg/L,La^(3+)掺杂改性纳米TiO_(2)纤维的浓度为15 mg/10 mL条件下,催化10 min的降解率为63.41%,催化70 min的降解率即可达到99.87%,比未掺杂TiO_(2)纳米纤维的降解率提高了6.36%,可见,La^(3+)的掺杂提高了TiO_(2)光催化降解速率,所需要的时间减少了。 展开更多
关键词 La^(3+)掺杂 TiO_(2) 光催化剂 染料降解
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坡缕石-In_(2)O_(3)/In_(2)S_(3)复合材料光催化降解甲基橙
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作者 王涛 胡美凤 +2 位作者 文娜 常玥 查飞 《精细化工》 EI CAS CSCD 北大核心 2024年第8期1824-1832,共9页
以In_(2)O_(3)、硫代乙酰胺、坡缕石(PGS)为原料,采用水热法制备了PGS负载In_(2)O_(3)/In_(2)S_(3)的复合材料(PGS-In_(2)O_(3)/In_(2)S_(3)),通过XRD、SEM、TEM、BET、紫外-可见漫反射光谱对PGS-In_(2)O_(3)/In_(2)S_(3)进行了表征,测... 以In_(2)O_(3)、硫代乙酰胺、坡缕石(PGS)为原料,采用水热法制备了PGS负载In_(2)O_(3)/In_(2)S_(3)的复合材料(PGS-In_(2)O_(3)/In_(2)S_(3)),通过XRD、SEM、TEM、BET、紫外-可见漫反射光谱对PGS-In_(2)O_(3)/In_(2)S_(3)进行了表征,测试了其电化学交流阻抗谱(EIS),考察了不同酸化PGS质量分数(以酸化PGS和In_(2)O_(3)总质量计,下同)的PGS-In_(2)O_(3)/In_(2)S_(3)光催化降解甲基橙(MO)的性能、抗离子干扰和循环使用性能。结果表明,PGS-In_(2)O_(3)/In_(2)S_(3)的In_(2)O_(3)颗粒表面附着木耳状In_(2)S_(3)纳米片及针状PGS,其在200~580 nm区域有较强的光吸收。PGS质量分数为50%的50%PGS-In_(2)O_(3)/In_(2)S_(3)具有最佳的光催化降解MO活性,在可见光下照射30 min,20 mg50%PGS-In_(2)O_(3)/In_(2)S_(3)对30 m L质量浓度为20 mg/L的MO水溶液的光催化降解率为98.8%。超氧基自由基(·O_(2)^(-))、空穴(h^(+))是50%PGS-In_(2)O_(3)/In_(2)S_(3)光催化降解MO的主要活性物种,除H_(2)PO_(4)^(-)外,溶液中Cl^(-)、Na^(+)等常见离子对其光催化降解MO没有影响;50%PGS-In_(2)O_(3)/In_(2)S_(3)对孔雀石绿、罗丹明B、结晶紫、亚甲基蓝等染料均表现出较好的物理吸附和光催化降解效果。PGS与In_(2)O_(3)/In_(2)S_(3)间的内置电场降低了In_(2)O_(3)/In_(2)S_(3)光生载流子的复合率。 展开更多
关键词 In_(2)O_(3)/In_(2)S_(3) 坡缕石 光催化剂 光降解 染料 水处理技术
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Mo-Zn_(0.5)Cd_(0.5)S@NiCo_(2)S_(4)掺杂-异质结体系的制备及其双功能光催化性能研究 被引量:1
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作者 牛杰 王亮 +1 位作者 孟祥超 李春虎 《聊城大学学报(自然科学版)》 2024年第1期36-45,共10页
采用溶剂热与水热法制备了Mo-Zn_(0.5)Cd_(0.5)S@NiCo_(2)S_(4)掺杂-异质结光催化剂,系统表征了光催化剂的晶体结构、元素组成、微观形貌和光电性能,通过差分电荷密度的计算并阐释了电子转移方向。结果表明,Mo的掺杂改变了Zn_(0.5)Cd_(0... 采用溶剂热与水热法制备了Mo-Zn_(0.5)Cd_(0.5)S@NiCo_(2)S_(4)掺杂-异质结光催化剂,系统表征了光催化剂的晶体结构、元素组成、微观形貌和光电性能,通过差分电荷密度的计算并阐释了电子转移方向。结果表明,Mo的掺杂改变了Zn_(0.5)Cd_(0.5)S的晶格和能带结构,异质结的构筑增加了光催化活性位点,加快了电子转移速率。在可见光照射下,通过降解四环素(TC)溶液同时产氢来考察双功能光催化剂的活性。60 min内,TC的降解率可达75%,氢气产量达1146.72μmol/g/h。 展开更多
关键词 Zn_(0.5)Cd_(0.5)S NiCo_(2)S_(4) 光催化剂 异质结 产氢 光降解
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Surface-modified Ag@Ru-P25 for photocatalytic CO_(2) conversion with high selectivity over CH_(4) formation at the solid–gas interface 被引量:1
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作者 Chaitanya B.Hiragond Sohag Biswas +8 位作者 Niket SPowar Junho Lee Eunhee Gong Hwapyong Kim Hong Soo Kim Jin-Woo Jung Chang-Hee Cho Bryan M.Wong Su-Il In 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期182-196,共15页
Systematic optimization of the photocatalyst and investigation of the role of each component is important to maximizing catalytic activity and comprehending the photocatalytic conversion of CO_(2) reduction to solar f... Systematic optimization of the photocatalyst and investigation of the role of each component is important to maximizing catalytic activity and comprehending the photocatalytic conversion of CO_(2) reduction to solar fuels.A surface-modified Ag@Ru-P25 photocatalyst with H_(2)O_(2) treatment was designed in this study to convert CO_(2) and H_(2)O vapor into highly selective CH4.Ru doping followed by Ag nanoparticles(NPs)cocatalyst deposition on P25(TiO_(2))enhances visible light absorption and charge separation,whereas H_(2)O_(2) treatment modifies the surface of the photocatalyst with hydroxyl(–OH)groups and promotes CO_(2) adsorption.High-resonance transmission electron microscopy,X-ray photoelectron spectroscopy,X-ray absorption near-edge structure,and extended X-ray absorption fine structure techniques were used to analyze the surface and chemical composition of the photocatalyst,while thermogravimetric analysis,CO_(2) adsorption isotherm,and temperature programmed desorption study were performed to examine the significance of H_(2)O_(2) treatment in increasing CO_(2) reduction activity.The optimized Ag1.0@Ru1.0-P25 photocatalyst performed excellent CO_(2) reduction activity into CO,CH4,and C2H6 with a~95%selectivity of CH4,where the activity was~135 times higher than that of pristine TiO_(2)(P25).For the first time,this work explored the effect of H_(2)O_(2) treatment on the photocatalyst that dramatically increases CO_(2) reduction activity. 展开更多
关键词 gas-phase CO_(2) reduction H_(2)O_(2) treatment plasmonic nanoparticles solar fuel photocatalyst surface modification
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分级中空结构TiO_(2)纳米微球光催化剂的制备及其性能分析
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作者 荣雪超 古满意 +3 位作者 陈俊宇 祝强韬 戚栋明 孙阳艺 《浙江理工大学学报(自然科学版)》 2024年第4期447-456,共10页
以双(乙酰丙酮基)二异丙基钛酸酯与双-[γ-(三乙氧基硅)丙基]-四硫化物为起始材料,通过水解-缩合反应合成实心TiO_(2)-SiO_(2)纳米微球;将这些微球经碱性水热反应和后续高温煅烧,制备分级中空结构TiO_(2)纳米微球光催化剂。通过TEM、DLS... 以双(乙酰丙酮基)二异丙基钛酸酯与双-[γ-(三乙氧基硅)丙基]-四硫化物为起始材料,通过水解-缩合反应合成实心TiO_(2)-SiO_(2)纳米微球;将这些微球经碱性水热反应和后续高温煅烧,制备分级中空结构TiO_(2)纳米微球光催化剂。通过TEM、DLS、FT-IR、EDS、XRD等表征手段对其形貌、单分散性、组分及晶体结构进行测试与分析;探讨碱性水热条件对分级中空结构形成的影响机理;研究煅烧温度对光催化剂性能的作用;通过罗丹明B的光催化降解实验来评估光催化剂的活性,并与商用P25进行对比。结果表明:所得纳米微球表面有明显的刺突、单分散性好,以钛酸盐为主要成分;钛酸盐的重结晶与二氧化硅的向内蚀刻是形成分级中空结构的关键;经500℃煅烧,所得催化剂保持分级中空结构,转变为锐钛矿相TiO_(2);其光催化性能卓越,对罗丹明B的降解速率常数k可达113.49×10^(-3)·min^(-1),是实心结构的3倍,是P25的1.45倍。分级中空结构TiO_(2)纳米微球光催化剂的制备方法简单有效,为光催化降解染料的研发提供了重要参考和理论指导。 展开更多
关键词 分级中空结构 TiO_(2) 纳米微球 光催化剂 降解
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面向CO_(2)还原应用的金属性光催化剂研究进展
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作者 张露云 李俊 《郑州大学学报(理学版)》 CAS 北大核心 2024年第3期82-87,共6页
金属性光催化剂由于其特殊的能带结构,可以吸收近红外光来驱动光催化反应,因而备受关注。首先,综述了金属性光催化剂的基本原理及其在光催化CO_(2)还原领域面临的挑战。其次,针对金属性光催化剂面临的瓶颈,总结了目前的几种改性策略在... 金属性光催化剂由于其特殊的能带结构,可以吸收近红外光来驱动光催化反应,因而备受关注。首先,综述了金属性光催化剂的基本原理及其在光催化CO_(2)还原领域面临的挑战。其次,针对金属性光催化剂面临的瓶颈,总结了目前的几种改性策略在提高金属性光催化剂CO_(2)光还原活性上的应用,重点介绍了催化剂结构与光催化性能之间的关系。最后,对金属性光催化剂的未来发展趋势及研究方向进行了展望。 展开更多
关键词 金属性光催化剂 近红外光 CO_(2)还原 光催化
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La^(3+)修饰对纳米ZnO/TiO_(2)复合粉体的光催化性能影响
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作者 汪鹏 许应生 +1 位作者 屠后为 徐茂红 《广州化工》 CAS 2024年第8期48-50,共3页
以La_(2)(SO_(4))3、Ti(SO_(4))2和ZnSO_(4)·7H_(2)O为原料,体积分数为40%的乙醇作溶剂,用共沉淀法制备La^(3+)修饰纳米ZnO/TiO_(2)复合光催化材料,初步研究了La^(3+)修饰对ZnO/TiO_(2)光催化性能的影响。有实验可知,用最佳镧掺杂... 以La_(2)(SO_(4))3、Ti(SO_(4))2和ZnSO_(4)·7H_(2)O为原料,体积分数为40%的乙醇作溶剂,用共沉淀法制备La^(3+)修饰纳米ZnO/TiO_(2)复合光催化材料,初步研究了La^(3+)修饰对ZnO/TiO_(2)光催化性能的影响。有实验可知,用最佳镧掺杂量为0.2%的Zn∶Ti=3∶10的ZnO/TiO_(2)样品,La^(3+)修饰ZnO/TiO_(2)纳米复合粉体对甲基橙降解率可达到38.4%。掺入金属La^(3+)有效地抑制ZnO/TiO_(2)纳米复合粉体粒子之间的团聚,比表面积增加,光催化活性明显增强。并采用XRD等测试手段对其进行表征。 展开更多
关键词 La^(3+)修饰 ZnO/TiO_(2) 光催化剂
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Synthesis of AgCl/Ti_(3)C_(2)@TiO_(2)Ternary Composite Photocatalysts for Photocatalytic Oxidation of 1,4-Dihydropyridine and Tetracycline Hydrochloride
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作者 Wu Hanliu Quan Yan +3 位作者 Liu Meiling Tian Xuemei Ren Chunguang Wang Zhonghua 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第2期10-23,共14页
AgCl/Ti_(3)C_(2)@TiO_(2)ternary composites were prepared to form a heterojunction structure between AgCl and TiO_(2)and introduce Ti3C2 as a cocatalyst.The as-prepared AgCl/Ti_(3)C_(2)@TiO_(2)composites showed higher ... AgCl/Ti_(3)C_(2)@TiO_(2)ternary composites were prepared to form a heterojunction structure between AgCl and TiO_(2)and introduce Ti3C2 as a cocatalyst.The as-prepared AgCl/Ti_(3)C_(2)@TiO_(2)composites showed higher photocatalytic activity than pure AgCl and Ti_(3)C_(2)@TiO_(2)for photooxidation of a 1,4-dihydropyridine derivative(1,4-DHP)and tetracycline hydrochloride(TCH)under visible light irradiation(λ>400 nm).The photocatalytic activity of AgCl/Ti_(3)C_(2)@TiO_(2)composites depended on Ti_(3)C_(2)@TiO_(2)content,and the catalytic activity of the optimized samples were 6.9 times higher than that of pure AgCl for 1,4-DHP photodehydrogenation and 7.3 times higher than that of Ti_(3)C_(2)@TiO_(2)for TCH photooxidation.The increased photocatalytic activity was due to the formation of a heterojunction structure between AgCl and TiO_(2)and the introduction of Ti3C2 as a cocatalyst,which lowered the internal resistance,sped up the charge transfer,and increased the separation efficiency of photogenerated carries.Photogenerated holes and superoxide radical anions were the major active species in the photocatalytic process. 展开更多
关键词 AgCl/Ti_(3)C_(2)@TiO_(2) composite photocatalyst COCATALYST heterojunction structure in situ solvothermal growth method
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窄带隙β-CuFeO_(2)铁电光催化剂性质及表面析氧反应特性
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作者 吕东昊 徐兰兰 刘孝娟 《应用化学》 CAS CSCD 北大核心 2024年第7期1010-1023,共14页
铜铁矿(delafossite)型CuFeO_(2)具有窄带隙、良好稳定性被广泛用于光催化领域的研究,而其中心对称的层状结构使得光生载流子容易复合,限制了其光催化效果。β-CuFeO_(2)是一种具有相稳定,窄带隙,强极化的本征铁电半导体,利用其内禀的... 铜铁矿(delafossite)型CuFeO_(2)具有窄带隙、良好稳定性被广泛用于光催化领域的研究,而其中心对称的层状结构使得光生载流子容易复合,限制了其光催化效果。β-CuFeO_(2)是一种具有相稳定,窄带隙,强极化的本征铁电半导体,利用其内禀的铁电极化性质,构建光生电子空穴生成位点交替排列的[011]表面,在铁电内建电场作用下促进电荷分离,从而提升光催化性能。基于第一性原理计算,本文首先确定β-CuFeO_(2)具有热力学稳定性,磁基态为C型反铁磁,且带隙为1.37 eV的直接带隙半导体,理论铁电极化为83.466μC/cm^(2),是良好的光催化剂载体。进一步地,以表面析氧反应(OER)为模型,通过构建非极化表面[100]、[010]和极化表面[001]、[011]研究铁电极化对OER的影响。结果表明,β-CuFeO_(2)的表面价带顶氧化还原电势大部分大于水氧化电势(1.23 eV),且极化表面更易形成。此外,在极化方向上,完全暴露Cu-O原子,Cu,Fe原子层交替排列的[011]表面最易吸附水分子且具有最优OER催化活性。对[011]表面OER决速步骤进行电子结构分析,发现在*O中间体上具有2个电子口袋,反应生成*OOH后消耗一个电子口袋,即空轨道上得到电子。这是[011]极化方向表面OER决速步骤的内在机理。本工作构建了β-CuFeO_(2)铁电半导体并通过理论模拟计算了其基本性质,构建了不同方向表面研究铁电极化对光催化OER活性的影响,将为铁电光催化剂设计提供理论依据。 展开更多
关键词 β-CuFeO_(2) 第一性原理计算 密度泛函理论 光催化 析氧反应 铁电极化
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Boosting CO_(2)photoreduction by synergistic optimization of multiple processes through metal vacancy engineering
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作者 Jinlong Wang Dongni Liu +3 位作者 Mingyang Li Xiaoyi Gu Shiqun Wu Jinlong Zhang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期202-212,共11页
The photoreduction of greenhouse gas CO_(2)using photocatalytic technologies not only benefits en-vironmental remediation but also facilitates the production of raw materials for chemicals.Howev-er,the efficiency of C... The photoreduction of greenhouse gas CO_(2)using photocatalytic technologies not only benefits en-vironmental remediation but also facilitates the production of raw materials for chemicals.Howev-er,the efficiency of CO_(2)photoreduction remains generally low due to the challenging activation of CO_(2)and the limited light absorption and separation of charge.Defect engineering of catalysts rep-resents a pivotal strategy to enhance the photocatalytic activity for CO_(2),with most research on met-al oxide catalysts focusing on the creation of anionic vacancies.The exploration of metal vacancies and their effects,however,is still underexplored.In this study,we prepared an In2O3 catalyst with indium vacancies(VIn)through defect engineering for CO_(2)photoreduction.Experimental and theo-retical calculations results demonstrate that VIn not only facilitate light absorption and charge sepa-ration in the catalyst but also enhance CO_(2)adsorption and reduce the energy barrier for the for-mation of the key intermediate*COOH during CO_(2)reduction.Through metal vacancy engineering,the activity of the catalyst was 7.4 times,reaching an outstanding rate of 841.32μmol g(-1)h^(-1).This work unveils the mechanism of metal vacancies in CO_(2)photoreduction and provides theoretical guidance for the development of novel CO_(2)photoreduction catalysts. 展开更多
关键词 photocatalyst CO_(2)photoreduction Indium oxide Metal vacancy Defect
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The photo-decomposition and self-restructuring dynamic equilibrium mechanism of Cu_(2)(OH)_(2)CO_(3)for stable photocatalytic CO_(2)reduction
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作者 Yaqing Zhi Haoning Mao +5 位作者 Guangxing Yang Qiao Zhang Zhiting Liu Yonghai Cao Siyuan Yang Feng Peng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期104-112,共9页
Developing suitable photocatalysts and understanding their intrinsic catalytic mechanism remain key challenges in the pursuit of highly active,good selective,and long-term stable photocatalytic CO_(2)reduction(PCO_(2)... Developing suitable photocatalysts and understanding their intrinsic catalytic mechanism remain key challenges in the pursuit of highly active,good selective,and long-term stable photocatalytic CO_(2)reduction(PCO_(2)R)systems.Herein,monoclinic Cu_(2)(OH)_(2)CO_(3)is firstly proven to be a new class of photocatalyst,which has excellent catalytic stability and selectivity for PCO_(2)R in the absence of any sacrificial agent and cocatalysts.Based on a Cu_(2)(OH)_(2)^(13)CO_(3)photocatalyst and 13CO_(2)two-sided^(13)C isotopic tracer strategy,and combined with in situ diffused reflectance infrared Fourier transform spectroscopy(DRIFTS)analysis and density functional theory(DFT)calculations,two main CO_(2)transformation routes,and the photo-decomposition and self-restructuring dynamic equilibrium mechanism of Cu_(2)(OH)_(2)CO_(3)are definitely revealed.The PCO_(2)R activity of Cu_(2)(OH)_(2)CO_(3)is comparable to some of state-of-the-art novel photocatalysts.Significantly,the PCO_(2)R properties can be further greatly enhanced by simply combining Cu_(2)(OH)_(2)CO_(3)with typical TiO_(2)to construct composites photocatalyst.The highest CO_(2)and CH_(4)production rates by 7.5 wt%Cu_(2)(OH)_(2)CO_(3)-TiO_(2)reach 16.4μmol g^(-1)h^(-1)and 116.0μmol g^(-1)h^(-1),respectively,which are even higher than that of some of PCO_(2)R systems containing sacrificial agents or precious metals modified photocatalysts.This work provides a better understanding for the PCO_(2)R mechanism at the atomic levels,and also indicates that basic carbonate photocatalysts have broad application potential in the future. 展开更多
关键词 CO_(2)photocatalytic reduction PHOTOCATALYSIS Basic copper carbonate SELF-RECONSTRUCTION photocatalyst
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Internal electric field modulation by copper vacancy concentration of cuprous sulfide nanosheets for enhanced selective CO_(2) photoreduction
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作者 Xian Shi Weidong Dai +4 位作者 Xiaoqian Li Yang Bai Qin Ren Yao Lei Xing'an Dong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期324-330,共7页
Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a ch... Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a challenge.Herein,cuprous sulfide nanosheets with different Cu vacancy concentration were employed to study IEF modulation and corresponding direct charge transfer.Among the samples,Cu_(1.8)S nanosheets possessed intensified IEF intensity compared with those of Cu_(2)S and Cu_(1.95)S nanosheets,suggesting that an enhanced IEF intensity could be achieved by introducing more Cu vacancies.This intensified IEF of Cu_(1.8)S nanosheets induced numerous photogenerated electrons to migrate to its surface,and the dissociative electrons were then captured by Cu vacancies,resulting in efficient charge separation spatially.In addition,the Cu vacancies on Cu_(1.8)S nanosheets accumulated electrons as active sites to lower the energy barrier of rate-determining step of CO_(2)photoreduction,leading to the selective conversion of CO_(2)to CO.Herein,the manipulation of IEF intensity through Cu vacancy concentration regulation of cuprous sulfide photocatalysts for efficient charge separation has been discussed,providing a scientific strategy to rationally improve photocata lytic performances for solar energy conversion. 展开更多
关键词 Internal electric field intensity Cuprous sulfide photocatalysts Cu vacancies Charge separation Selective CO_(2) photoreduction
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Ni掺杂提升MoS_(2)的助催化活性用于ZnIn_(2)S_(4)光催化产氢及有毒Cr(Ⅵ)还原
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作者 陈文轩 乔秀清 +4 位作者 李晨 王紫昭 侯东芳 孙博婧 李东升 《功能材料》 CAS CSCD 北大核心 2024年第5期5177-5187,共11页
过渡金属硫化物MoS_(2)吸附H^(+)的吉布斯自由能接近于零,被认为是一种很有前途的产氢助催化剂。然而,MoS_(2)助催化剂的活性位点暴露有限,极大的限制了其活性。以Ni-BDC微球作为Ni源和模板,通过水热法成功合成了镍掺杂的Ni-MoS_(2)助... 过渡金属硫化物MoS_(2)吸附H^(+)的吉布斯自由能接近于零,被认为是一种很有前途的产氢助催化剂。然而,MoS_(2)助催化剂的活性位点暴露有限,极大的限制了其活性。以Ni-BDC微球作为Ni源和模板,通过水热法成功合成了镍掺杂的Ni-MoS_(2)助催化剂。该助催化剂可以明显的提高ZnIn_(2)S_(4)的光催化析氢活性活性,经过优化后的光催化剂(表示为NMS/ZIS-10)的氢气释放速率最高,达到4.17 mmol·g^(-1)·h^(-1),分别是纯ZnIn_(2)S_(4)和MoS_(2)/ZnIn_(2)S_(4)光催化剂的12.26倍和2.72倍。此外,NMS/ZIS-10还表现出电荷分离促进的毒性Cr(Ⅵ)还原活性。实验数据表明,Ni-MoS_(2)/ZnIn_(2)S_(4)优异的光催化性能主要源于其Ni掺杂引起的活性位点的增加、光吸收能力的增强、电荷载流子分离的提升以及电子寿命的延长。研究结果为优化设计高性能Mo基助催化剂提供了有价值的参考。 展开更多
关键词 ZnIn_(2)S_(4) MoS_(2) 掺杂 光催化剂 Cr(Ⅵ)还原 产氢
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等离子体电解氧化法制备多孔TiO_(2)/V_(2)O_(5)复合物膜层及其增强光催化产氢活性
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作者 贾方舟 姚忠平 姜兆华 《材料科学与工艺》 CAS CSCD 北大核心 2024年第2期12-19,共8页
较差的光催化产氢效率极大地阻碍了TiO_(2)光催化剂的工业化应用。为此,本文在含有NH_(4)VO_(3)的磷酸盐溶液中,采用等离子体电解氧化(PEO)法制备了多孔TiO_(2)/V_(2)O_(5)复合膜光催化剂,通过扫描电子显微镜(SEM)、能谱仪(EDS)、X射线... 较差的光催化产氢效率极大地阻碍了TiO_(2)光催化剂的工业化应用。为此,本文在含有NH_(4)VO_(3)的磷酸盐溶液中,采用等离子体电解氧化(PEO)法制备了多孔TiO_(2)/V_(2)O_(5)复合膜光催化剂,通过扫描电子显微镜(SEM)、能谱仪(EDS)、X射线衍射(XRD)、X射线光电子谱(XPS)和紫外可见漫反射光谱(UV-Vis DRS)对其组成、结构及光吸收性质进行了表征,并采用气相色谱评价了薄膜催化剂的光催化产氢性能,研究了电解液中NH_(4)VO_(3)含量对膜的结构、组成和光催化产氢性能的影响。结果表明:复合膜催化剂主要由锐钛矿和金红石型TiO_(2)组成,具有微孔结构,V_(2)O_(5)主要以无定形形式存在于膜中,与TiO_(2)有很强的相互作用,影响TiO_(2)的晶面间距。研究发现,元素V抑制了TiO_(2)的结晶和金红石型TiO_(2)的形成,扩大了薄膜的光学吸收范围。针对Na_(2)S+Na_(2)SO_(3)溶液中的光催化产氢性能的研究显示,在质量浓度为1 g/L NH_(4)VO_(3)的电解液中制备的TiO_(2)/V_(2)O_(5)薄膜的光催化活性最高,优于近年来报道的其他光催化剂。光催化重复实验表明,该复合膜催化剂具有较高的稳定性和较为恒定的光催化活性。 展开更多
关键词 TiO_(2) V_(2)O_(5) 膜层光催化剂 等离子体电解氧化 产氢
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