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Fe_(2)O_(3)/TiO_(2)/reduced graphene oxide-driven recycled visible-photocatalytic Fenton reactions to mineralize organic pollutants in a wide pH range

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Journal of Environmental Sciences 2023年第12期134卷 11-20页

作者： Ru Zheng Dehong Yang Yao Chen zhenfeng bian Hexing Li Ministry of Education Key Laboratory of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Normal UniversityShanghai 200234China

Photocatalytic Fenton reactions combined the advantages from both photocatalysis and Fenton reaction in mineralizing organic pollutants. The key problems are the efficiency and recycling stability. Herein, we reported a novel Fe_(2)O_(3)/TiO_(2)/reduced graphene oxide(FTG) nanocomposite synthesized by a facile solvothermal method. The TiO_(2)in FTG degraded organic pollutants and mineralized intermediates via photocatalysis under visible light irradiation, which could also promote Fenton reaction by accelerating Fe^(3+)-Fe^(2+)recycle. Meanwhile, the Fe_(2)O_(3)rapidly degraded organic pollutants via Fenton reactions, which also promoted photocatalysis by enhancing visible light absorbance and diminishing photoelectronhole recombination. The high distribution of TiO_(2)and Fe_(2)O_(3)on rGO, together with their strong interaction resulted in enhanced synergetic cooperation between photocatalysis and Fenton reactions, leading to the high mineralization efficiency of organic pollutants. More importantly, it could also inhibit the leaching of Fe species, leading to the long lifetime of FTG during photocatalytic Fenton reactions in a wide pH range from 3.4 to 9.2.

关键词： Fe_(2)O_(3)/TiO_(2)/rGO nanocomposite(FTG) Visible-photocatalytic Fenton reactions Synergetic effect Pollutant mineralization Strong durability in a wide pH range

Surface modification of phosphate ion to promote photocatalytic recovery of precious metals

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Chinese Chemical Letters 2023年第2期34卷 290-294页

作者： Qianyu Qiao Yao Chen Yue Wang Yuqing Ren Jiazhen Cao Fengjiao Huang zhenfeng bian MOE Key Laboratory of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Normal UniversityShanghai 200234China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438China

Photocatalytic recovery,a novel precious metal recycling technology,dedicates to solving the environmental and energy consumption problems caused by traditional *** activation of molecular oxygen (O_(2)) is one of the most critical steps in the whole ***,we regulated the different adsorption intensity of oxygen on the surface by designing phosphate (PO_(4)^(3-)) modified titanium oxide(TiO_(2)).The results show that the adsorption of oxygen on the photocatalyst surface is gradually enhanced,which effectively improves the dissolution rate of precious ***_(4)^(3-)modification increased the photocatalytic dissolution rate of gold (Au) by 2.8 *** photocatalytic activity of other precious metals dissolution (such as palladium (Pd),platinum (Pt),rhodium (Rh),ruthenium (Ru) and iridium (Ir)) was also significantly *** is applied to the recovery of precious metals from spent catalysts and electronic devices to significantly promote the recovery *** indicates the direction for designing more efficient photocatalysts for precious metal recovery.

关键词： Photocatalysis Precious metal recovery Molecular oxygen activation Carrier separation Phosphate modification

Passive imaging through dense scattering media

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Photonics Research 2024年第1期12卷 134-140页

作者： YAOMING bian FEI WANG YUANZHE WANG zhenfeng FU HAISHAN LIU HAIMING YUAN GUOHAI SITU Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China

Imaging through non-static and optically thick scattering media such as dense fog,heavy smoke,and turbid water is crucial in various ***,most existing methods rely on either active and coherent light illumination,or image priors,preventing their application in situations where only passive illumination is *** this study we present a universal passive method for imaging through dense scattering media that does not depend on any prior *** the selection of small-angle components out of the incoming information-carrying scattering light and image enhancement algorithm that incorporates timedomain minimum filtering and denoising,we show that the proposed method can dramatically improve the signal-to-interference ratio and contrast of the raw camera image in outfield experiments.

关键词： scattering media illumination

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光催化技术在能源环境中的发展与应用

太阳能 2024年第7期 50-61页

作者：杨杰陈香刘昌昊李朝升卞振锋陈春城中国科学院化学研究所光化学院重点实验室北京100190 上海师范大学上海200234 南京大学南京210093

光催化技术是一种高效的光能利用方式,通过激发催化剂产生表面高能活性物种,进而引发表面化学反应,实现光能到化学能的转化或加速化学反应速度。近年来,光催化技术在环境净化、能源转换和资源回收等领域得到了广泛研究。综述了近几年光... 详细信息

光催化技术是一种高效的光能利用方式,通过激发催化剂产生表面高能活性物种,进而引发表面化学反应,实现光能到化学能的转化或加速化学反应速度。近年来,光催化技术在环境净化、能源转换和资源回收等领域得到了广泛研究。综述了近几年光催化技术的发展与应用,就光催化技术面临的未来挑战和发展前景进行了探讨。在环境净化方面,光催化技术被用于降解有机污染物,以及去除大气污染物和温室气体;在能源转换领域,光催化技术被应用于太阳能转换、分解水制氢,以及CO_(2)还原成多碳、高价值燃料;在资源回收领域,光催化技术可以实现对废弃电子废料中贵金属的有效回收。

关键词：光催化太阳能污染物降解水分解制氢贵金属回收 CO_(2)还原

Effect of Ti（lll） Surface Defects on the Process of Photocatalytic Reduction of Hexavalent Chromium

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Chinese Journal of Chemistry 2017年第2期35卷 203-208页

作者： Hongxia Qin Yingying bian Yaxi Zhang Longfei Liu zhenfeng bian Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Normal University Shanghai 200234 China

In this paper, the process of photocatalytic reduction of hexavalent chromium was investigated over Ti3＋- modified TiO2 photocatalysts. The Ti3＋ surface defects were repaired by annealing as-prepared sample at different temperatures to control the amount of Ti3＋ sites. The samples were characterized by SEM, XRD, BET, UV-Vis absorption, EPR and XPS. The results showed Ti3＋ defects were successfully doped in TiO2. The surface selective adsorption of hexavalent chromium [Cr2072 （Cr（VI））] and the desorption of trivalent chromium [Cr3＋（Cr（III））] were investigated during the process ofphotocatalytic reduction positive charges due to more Ti3＋ defects on the surface show a Accordingly, the surface positive reduction of Cr（VI）. charges controlled by the Ti3＋ Zeta potential results presented that the increased significant improvement for adsorption of Cr（VI）. defects play important roles in the photocatalytic

关键词： Ti3+ modification titanium dioxide photocatalytic reduction hexavalent chromium surface selective adsorption and desorption

Enhancing Photocatalytic Performance of NH 2-UIO66 by Defective Structural Engineering

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Transactions of Tianjin University 2021年第2期27卷 147-154页

作者： Zhenmin Xu Jiazhen Cao Xiang Chen Liyi Shi zhenfeng bian Research Center of Nano Science and Technology Shanghai UniversityShanghai 200444China The Education Ministry Key Laboratory of Resource Chemistry Shanghai Key Laboratory of Rare Earth Function MaterialsShanghai Normal UniversityShanghai 200444China

NH_(2)-UIO66(NU)is a promising photocatalyst for the reduction of Cr(VI)to low-toxic Cr(III)driven by visible light under ambient ***,the main limitation in this process is the ineffi cient ligand to metal charge transfer(LMCT)of photo-excited electrons,which is caused by inherent energy gap(ΔE_(LMCT)).This study synthesized the defective NU(NUXH,where X is the molar equivalent of the modulator)with reducedΔE_(LMCT)through linkers removal via acid *** electronic structure of NUX-H was systematically investigated,and the results indicated that the structural defects in NUX-H strongly altered the environment of the Zr ***,they substantially lowered the energy of the unoccupied d orbitals(LUMO),which was benefi cial to effi cient LMCT,resulting in an improved photocatalytic activity of NUX-H toward high-concentration(100 mg/L)Cr(VI)*** to NU with defect-free structure,the reducing rate of Cr(VI)was increased by 47 *** work introduced an alternative strategy in terms of designing effi cient photocatalysts for reducing Cr(VI)under ambient conditions.

关键词： NH_(2)-UIO66 Defective structure Effi cient LMCT Photocatalysis Cr(VI)reduction

Self-powered electrochemical system by combining Fenton reaction and active chlorine geheration for organic contaminant treatment

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Nano Research 2019年第11期12卷 2729-2735页

作者： Yawei Feng Kai Han Tao Jiang zhenfeng bian Xi Liang Xia Cao Hexing Li Zhong Lin Wang CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and SensorBejing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBejing 100083China School of Nanoscience and Technology University of Chinese Academy of Sciences Beijing 100049China Education Ministry Key and International Joint Lab of Resoure Chemistry and Shanghai Key Lab of Rare Earth Functional Materials Shanghai Normal UniversityShanghai 200234China School of Environmental and Chemical Engineering Shanghai Uriversity of Elecric PowerShanghai 200090China School of Material Science and Engineering Georgia Institute of Technology AtlantaGA 30332USA

Environmental deterioration,especially water pollution,is widely dispersed and could affect the quality of people's life at *** the sewage treatment plants are constructed to meet the demands of cities,distributed treatment units are still in request for the supplementary of centralized purification beyond the range of *** degradation can reduce organic pollution to some degree,but it has to be *** nanogenerator(TENG)is a newly-invented technology for low-frequency mechanical energy ***,by integrating a rotary TENG(R-TENG)as electric power source with an electrochemical cell containing a modified graphite felt cathode for hydrogen peroxide(H2O2)along with hydroxyl radical(·OH)generation by Fenton reaction and a platinum sheet anode for active chlorine generation,a self-powered electrochemical system(SPECS)was *** the driven of mechanical energy or wind flow,such SPECS can efficiently degrade dyes after power management in neutral condition without any O2 *** work not only provides a guideline for optimizing self-powered electrochemical reaction,but also displays a strategy based on the conversion from distributed mechanical energy to chemical energy for environmental remediation.

关键词： self-powered electrochemistry Fenton reaction active chlorine organic contaminant degradation

Pd/PbTiO3表面的热电效应增强光催化Suzuki偶联反应

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Chinese Journal of Catalysis 2020年第10期41卷 1674-1681页

作者：闻洁雅凌丽丽陈瑶卞振锋上海师范大学资源化学教育部重点实验室稀土功能材料上海重点实验室上海200234 上海电力大学上海201303

发展绿色化学技术是21世纪化学研究的一个重要方向,其主要目标是取代那些对环境有害的耗能过程,其中新能源尤其是太阳能开发利用的重要性愈加突显.光催化作为一种低能耗、高效、无二次污染的技术,以其反应条件温和、能直接利用太阳能转... 详细信息

发展绿色化学技术是21世纪化学研究的一个重要方向,其主要目标是取代那些对环境有害的耗能过程,其中新能源尤其是太阳能开发利用的重要性愈加突显.光催化作为一种低能耗、高效、无二次污染的技术,以其反应条件温和、能直接利用太阳能转化为化学能的优势而备受科研人员关注.光催化技术是利用半导体材料作为催化剂的光催化过程,当能量高于半导体禁带宽度的光子照射半导体材料时,半导体材料上的价带电子发生带间跃迁,从价带跃迁到导带,从而产生带正电荷的光致空穴和带负电荷的光生电子.光致空穴的强氧化能力和光生电子的还原能力导致半导体光催化剂引发一系列光催化反应的发生.光催化选择性氧化还原体系的出现和应用极大地满足了人们对能源和环境的要求.在光催化选择性氧化还原体系中,反应发生所需要的条件比传统催化温和,同时它也避免了一些危险的强氧化剂和还原性物质的使用.但是在一些过程中,催化反应常常需要在高温下进行.传统加热是由外部热源通过热辐射由表及里的热传导的方式进行的,并且为了达到催化温度,需使催化剂床层整体升温.而微波诱导的催化方法与常规不同,微波不仅加热速度快、能源利用率高,而且加热均匀、温度梯度小,因此微波化学作为一门新兴的前沿交叉学科,已在广泛的实际应用中显示出强大的生命力.将光催化技术与微波联用可能会取得意想不到的成果.微波与光催化系统相结合是抑制光生电子–空穴复合并增强光催化反应性能的一种有效方法.本文通过简单的水热反应制备了单晶PbTiO3纳米片.由XRD谱可以看出,所有衍射峰均归属于四方钙钛矿相PbTiO3,紫外-可见漫反射光谱表明单晶PbTiO3在紫外光区域有强吸收,在400–450 nm处还存在微弱的可见光吸收.另外,负载了Pd纳米颗粒之后,在可见光区域吸收明显增强.这说明我们成功制备了一种既能利用微波又能利用光催化的Pd/PbTiO3催化剂.利用PbTiO3晶体的热释电效应在微波场下与紫外光协同促进以溴苯引导的Suzuki偶联反应发生,反应速度和选择性显著提高.在微波场和紫外光的协同作用下, PbTiO3晶体的热电效应可以将热能转换为电能,产生正电荷和负电荷(q+和q–),而Pd纳米粒子则显著提高了光催化过程的量子效率.光催化技术协同微波场可以直接作用于有机化学反应,以独特的方式促进甚至改变各种化学反应过程.

关键词：光催化热释电微波 Suzuki偶联反应

具有光增强芬顿活性的有序介孔Fe/TiO_2的制备（英文）

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Chinese Journal of Catalysis 2019年第5期40卷 631-637页

作者：许振民郑茹陈瑶朱建卞振锋上海师范大学资源化学教育部重点实验室稀土功能材料上海市重点实验室上海200234

Fenton反应能够无选择性地降解有机物,甚至能够处理一些不能被生物降解的污染物,其原理为过氧化氢(H_2O_2)和亚铁离子(Fe^(2+))在酸性溶液中生成具有强氧化性的羟基自由基(·OH),后者将有机物氧化分解.因此,Fenton反应在处理环境问题中... 详细信息

Fenton反应能够无选择性地降解有机物,甚至能够处理一些不能被生物降解的污染物,其原理为过氧化氢(H_2O_2)和亚铁离子(Fe^(2+))在酸性溶液中生成具有强氧化性的羟基自由基(·OH),后者将有机物氧化分解.因此,Fenton反应在处理环境问题中占有重要地位.将光催化与Fenton反应结合,相比单独的Fenton反应可提高氧化矿化性能,大大加快反应速率,减少H_2O_2使用量,降低成本,拓宽反应pH范围,其协同作用主要体现在两方面:(1)光催化产生的电子加速Fe^(3+)转变成Fe^(2+),促进Fenton反应进行;(2)Fenton反应中的H_2O_2与光生电子反应降低了电子-空穴的复合率,从而提高光催化降解效率.由于协同作用的存在,污染物的降解效率大大增加.到目前为止,Fenton反应中催化剂的载体多为惰性多孔材料,如沸石、粘土、金属氧化物、介孔二氧化硅、多孔碳和sp2型石墨(石墨烯、氧化石墨烯、碳纳米管等)等具有较大比表面积的材料.通常,增加载体的表面积有利于活性位点的分散,但是大比表面积的载体材料会削弱铁催化剂组分之间的相互作用,导致催化剂稳定性差,循环利用几次后会增加铁浸出量.因此,寻求大比表面积和高稳定性的光催化材料依然是巨大的挑战.本文首次通过蒸发诱导自组装法成功制备了Fe离子修饰的有序介孔TiO_2(FT-X),并通过XRD、BET、TEM、XPS和UV-Vis等分析手段对催化剂的结构进行了表征,同时以光芬顿降解罗丹明B反应考察了pH、污染物浓度及载体(TiO_2)结构对催化性能的影响.结果表明,由于Fe离子修饰减小了TiO_2的禁带宽度,FT复合材料具有更宽的可见光响应距离和更强的可见光吸收,在光芬顿反应过程中可以迅速转移电子,避免电子-空穴对的重组,同时加速了Fe^(3+)和Fe^(2+)的转化,显著提高了催化剂的催化性能.另外,将Fe离子原位锚定在有序介孔TiO_2的孔壁上,使FT具有规整的孔道结构和高的比表面积.与不规则多孔材料相比,一方面,该结构有利于活性位点的暴露,另一方面,有序的孔道更有利于光吸收和溶质传输.同时,Fe离子与载体之间具有较强的相互作用,可以有效地抑制反应过程中Fe离子的流失,FT-1.5样品(Fe:Ti摩尔比为1.5%)在经过5次循环测试后依然保持较高的催化活性.

关键词：有序介孔TiO2 铁离子掺杂光芬顿光催化