PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
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2022
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IF 7.926
Haoran Leng,Zhiying Lv,Haili Tan,Yuhong Jia,Hong You
As a representative pollutant with carcinogenesis, mutagenicity and teratogenicity , nitrobenzene (NB) has devastating harm to human health. Herein, a unique three-dimensional (3D) stack Z-scheme photoelectrocatalytic (PEC) system was built by self-assembled different photoelectrodes for efficient NB removal. The effect of initial NB, bias potential, pH and electrolyte concentration on NB removal efficiency were investigated. The intermediates and oxygen-active radicals were determined and analyzed by high performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), density functional theory (DFT) and electron paramagnetic resonance (EPR) to propose the NB degradation pathways and mechanism. The results showed that holes were utilized to produce ·OH to oxidize NB on the photoanode surface, the electrons excited from photocathode could reduce NB under UV irradiation; thereafter, the reduction product (aniline) was oxidized to phenol to achieve mineralization by the synergistic effect of anode (oxidation) and cathode (reduction). 3D stack Z-scheme PEC system exhibited a high NB degradation efficiency of 98.18% after 90 min reaction and a mineralization efficiency of 75.08% at 150 min. With ECOSAR software, the system toxicity was speculated. This study has advantages in NB removal and provides direction for other refractory organics.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2016
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IF 5.31
Dong Ma,Juan Wu,Mengchun Gao,Yanjun Xin,Tianjin Ma,Yuying Sun
An efficient visible-light-driven Z-scheme g -C 3 N 4 /RGO/Bi 2 WO 6 composite was fabricated by the hydrothermal method. The prepared g -C 3 N 4 /RGO/Bi 2 WO 6 composite were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), nitrogen sorption, Fourier transform infrared spectroscopy (FT-IR), diffuse reflectance spectroscopy (DRS) and X-ray photoelectron spectrometer (XPS). The photocatalytic activity of the g -C 3 N 4 /RGO/Bi 2 WO 6 composite was evaluated by the degradation of 2,4,6-trichlorophenol (TCP) under visible-light irradiation. The photochemical test and scavenging experiment showed the photogenerated electrons (e − ) and holes (h + ) had strong reducing capability and oxidation capability, respectively. The photocatalytic activity of the g -C 3 N 4 /RGO/Bi 2 WO 6 composite was higher than that of the pure g -C 3 N 4 , Bi 2 WO 6 , and g -C 3 N 4 /Bi 2 WO 6 during the TCP degradation, which could be due to the efficient visible-light utilization efficiency and the construction of Z-scheme. RGO served as a charge transmission bridge between the g -C 3 N 4 and the Bi 2 WO 6 , and the Z-scheme kept the electrons with high reducing capability in the conduction band (CB) of g -C 3 N 4 and the holes with high oxidation capability in the valence band (VB) of Bi 2 WO 6 . The photogenerated holes of Bi 2 WO 6 were the major active species in the TCP oxidative degradation, and the photogenerated electrons of g -C 3 N 4 were the major active species in the TCP dechlorination.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
CATALYSIS LETTERS
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2020
·Vol. 151
·期 3
·734-747
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IF 2.482
Zhang Xiaorui,Chen Chen,Jiang Caiyun,Zhou Haifei,Cao Wang,Wang Yuping
Abstract A new type of Ag 3 PO 4 /UiO-66-NH 2 Z-scheme heterojunction nanocomposite with visible light catalytic activity was successfully prepared. The synthesis of the composite was confirmed by XRD, FT-IR, SEM, TEM, EDS, XPS. The Ag 3 PO 4 /UiO-66-NH 2 Z-scheme heterojunction can effectively improve the utilization of visible light. The optimal Ag/U/1/4 composite has the highest degradation efficiency for methylene blue (MB, 30 mg/L) in 90 min (80%) and Norfloxacin (NOR, 10 mg/L) in 150 min (85%). The decrease of Nyquist radius and the enhancement of photocurrent response indicated that the combination of photogenerated electron–hole pair in Ag 3 PO 4 /UiO-66-NH 2 composite material is significantly inhibited. N 2 adsorption–desorption and zeta potential results indicated that biggish specific surface area and negative zeta potential value are more favorable for the adsorption of the cationic dye MB. The cyclic test verified the good stability of Ag 3 PO 4 /UiO-66-NH 2 heterojunction material. Furthermore, the photocatalytic degradation mechanism of MB was discussed by introducing different traps to inhibit the possible active substances in the degradation process. This work testified that an efficient photocatalytic composite based on metal–organic frameworks can be used for the degradation of pollutants. Graphic Abstract
研究领域:
材料科学
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环境科学
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光催化
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DOI
高影响因子
COMPOSITES PART B-ENGINEERING
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2021
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IF 9.078
Saipeng Zhou,Mingming Hou,Yulong Sun,Wenzhe Zhao,Honglin Wang,Quanhui Guo,Xin Yu,Xinqi Ma,Junwei Zhao
Preparation of high-performance semiconductor photocatalysts is often considered to be the challenge and focus in dealing with water contaminations, and attracts numerous concerns and research interests nowadays. In this work, high-performance Z-scheme AgI/(Na,F) doped g-C 3 N 4 composites were synthesized by facile calcination and in-situ deposition methods and employed for ultrahigh-performance degradation of broad-spectrum antibiotics contaminants. The prepared (Na,F) doped g-C 3 N 4 showed narrower bandgaps, enhanced solar-light absorption, and highly improved visible-light photocatalytic performance. Besides, the strong combined interfaces between AgI nanoparticles and (Na,F) doped g-C 3 N 4 was contributing to visible-light harvesting and highly boosted charge separation of the samples, among which AgI/(Na,F)–CN-40% composite presented the best visible-light photocatalytic performance. The photocatalytic reaction rate constant of the AgI/(Na,F)–CN-40% composite was as high as approximately 0.2007 min −1 , which was 65.80 times of pristine g-C 3 N 4 and 3.60 times of AgI, mainly because of the construction of direct Z-scheme charge transfer pathways between AgI and (Na,F) doped g-C 3 N 4 . Finally, the radical scavenger experiments, possible degradation pathways , and photocatalytic mechanism were also proposed.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Journal of Environmental Chemical Engineering
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2023
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IF 7.7
Ting Liang,Jingwen Wei,Shiming Zhang,Jinhang Yang,Jiangli Sun,Zuji Li,Zhihong Li,Zebin Yu,Shuangfei Wang,Yanping Hou
Design of photocatalysts with high-efficiency for sunlight utilization is one of the prerequisites for CO 2 photoreduction . Besides, modulating a stable electron-donating environment to meet the energy barrier for CO 2 reduction to CO is crucial. In this work, the ZnSe/Ag 2 Se/AgBr (ZAA) heterojunction was fabricated by growing the ZnSe on the AgBr surface accompanied by in-situ generation of Ag 2 Se between the two components by hydrothermal process. Results showed that the ZAA exhibited excellent light response ability over the full wavelength range. X-ray photoelectron spectroscopy (XPS) and electron spin resonance (ESR) demonstrated that the charge transfer of the ZAA conformed to dual Z-scheme mechanism, with the Ag 2 Se acting as an electron transfer bridge, which in turn acted as an electron reservoir to accelerate electron transfer, facilitating carriers’ separation. The highest CO yield of 54.14 µmol/g/h was obtained from the optimal ZAA-2, which was 11.76 and 10.44 times of pure ZnSe and Ag 2 Se, respectively. This work demonstrated the feasibility of a dual Z-scheme heterostructure with full spectrum response for offering stable electron-donating environment and improving electron transfer for enhanced photocatalytic activity.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
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2024
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IF 11.2
Tingting Yu,Bing Yang,Rong Zhang,Chenyu Yang,Arramel,Jizhou Jiang
The upsurge of interest in the emergence of photocatalytic fuel cell systems (PFC) presents an efficient and environmentally friendly approach to wastewater treatment. In this work, a Z-scheme coupled with an S-scheme heterojunction electrode was used in the PFC, utilizing TiO 2 /GO/g-C 3 N 4 as the photoanode and BiOAc 1– x Br x /BiOBr as the photocathode. We systematically align the band structures between the anode and cathode, which facilitates the electron transfer between the electrodes. Our attempt successfully demonstrates that collaborative power generation facilitates the high efficiency of tetracycline hydrochloride (TC) degradation at both electrodes. The photoanode achieved a 94.87 % degradation rate for TC, while the photocathode exhibited a 96.33 % degradation rate after 2 h, surpassing pristine BiOBr and BiOAc by factors of ∼5.3 and ∼3.8, respectively. Furthermore, this work proposed a mechanism for electron generation, transport, and pollutant degradation mechanism in the PFC. Intermediate substances generated during the degradation of TC were analyzed through high-performance liquid chromatography-mass spectrometry (HPLC-MS) and ultraviolet photoelectron spectroscopy (UPS), while the optimal degradation pathway was confirmed using density functional theory (DFT). The findings of this work establish the feasibility of efficiently degrading pollutants through PFC treatment, introducing a novel system where various heterojunctions in bipolar materials collaborate with photocatalysis to effectively generate electricity and enhance pollutant removal.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
OPTICAL MATERIALS
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2024
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IF 3.8
Mengyao Xue,Jingwei Han,Xing Dai,Yucai Ge,Yunhua Zhang,Zibin Hai
Cu 2 O–SiC/g-C 3 N 4 composite photocatalysts with excellent photocatalytic performance under visible light were synthesized for the first time via a facile approach combining calcination with hydrothermal reaction. Comprehensive characterization of the synthesized samples encompassing composition, morphology, structure and photoelectric properties was conducted utilizing techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), and electrochemical impedance spectroscopy (EIS). Results unequivocally demonstrate successful preparation of the ternary composite through Cu 2 O loading onto SiC/g-C 3 N 4 , evincing markedly elevated activity compared to individual counterparts and binary composites. Notably, in the presence of the prepared Cu 2 O–SiC/g-C 3 N 4 , the degradation rate of methyl orange reached 93.70 % under illumination with a visible LED light rated at 5 W. The notable enhancement in photocatalytic performance of the ternary composites is primarily ascribed to the synergistic effects stemming from the formation of p-n junctions between Cu 2 O and g-C 3 N 4 , alongside the Z-scheme configuration established between Cu 2 O and SiC. Free radical quenching experiments corroborated •O 2 − and h + as the principal redox species mediating the visible light quenching process. This study not only presents a feasible strategy for the fabrication of Cu 2 O-based ternary composites with significantly augmented photocatalytic performance but also delineates a novel avenue for the design and construction of composite photocatalysts facilitating enhanced charge-carrier generation and separation concomitantly.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2021
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IF 19.503
Xue Ma,Guowei Wang,Lifan Qin,Jue Liu,Bing Li,Yuanan Hu,Hefa Cheng
The transfer rate of photo-generated electrons is a critical factor that determines the photocatalytic efficiency of Z-scheme photocatalytic systems. Here, a novel Z-scheme g-C 3 N 4 -AQ-MoO 3 photocatalyst with anthraquinone (AQ) serving as an e – transfer channel for hydrogen production was proposed. Its enhanced photocatalytic activity is due to the accelerated transfer of e – in the form of charge inside AQ, which also suppresses the recombination of photo-generated e – and h + . In addition, the reduction area is significantly increased by the exfoliation of g-C 3 N 4 into thin layers. Due to the synergistic effect of rapid e – transfer and large reduction area, Z-scheme g-C 3 N 4 -AQ-MoO 3 has a high hydrogen production efficiency that can reach 2018 μmol/g with the presence of triethanolamine as a hole sacrificial agent after 180 min of simulated sunlight illumination. This work provides a new strategy to design and develop Z-scheme photocatalytic systems with excellent electron migration rates and high charge separation efficiency.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2025
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IF 9.7
Xiaosong Zhou,Jiabao Liang,Limei Xu,Siyu Wu,Minyi Xie,Qiongdan Liang,Jin Luo,Xuliang Fan,Xunfu Zhou,Xiaoqin Zhou
The photocatalytic efficiency of Black P is limited by its rapid carrier recombination and poor oxidation ability. In contrast, the photocatalytic efficiency of TiO 2 is limited by its rapid carrier recombination and poor visible light absorption capability. Given this, coupling Black P with TiO 2 to construct a heterojunction achieves complementary weaknesses. With an effective photocatalytic water splitting activity, Black P/TiO 2 produces hydrogen at a rate of 139.50 μmol h −1 g −1 under visible light, which is 4.73 times more than Black P’s. The main reason for the big increase in photocatalytic activity is that a Z-scheme heterojunction forms between Black P and TiO 2 . The internal built-in electric field promotes the recombination of electrons with low reduction potential and holes with low oxidation potential, achieving spatial separation of photogenerated electrons with high reduction potential and holes with high oxidation potential. This spatial separation endows the heterojunction photocatalyst with excellent redox capabilities.
研究领域:
材料科学
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环境科学
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产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2025
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IF 5.4
Jinxin Liu,Jinyuan Liu,Qichang Peng,Bin Wang,Xingwang Zhu,Xue Gao,Huaming Li,Hui Xu,Paul K. Chu
A Z-scheme heterojunction is designed and demonstrated to enhance the separation efficiency of photocatalytic carriers. In this paper, the 2D/2D Sb 2 WO 6 /g-C 3 N 4 (SWO/CN) Z-scheme heterojunction fabricated by electrostatic self-assembly has better degradation activity than individual Sb 2 WO 6 and g-C 3 N 4 . The rate constant K (0.0194 min −1 ) of RhB degradation by 40 % SWO/CN was higher than that of Sb 2 WO 6 (0.0054 min −1 ) and g-C 3 N 4 (0.0039 min −1 ). The rate constant K of 40 % SWO/CN for MBT degradation was 0.4391 h −1 , which was 2.96 and 9.32 times that of g-C 3 N 4 (0.1484 h −1 ) and Sb 2 WO 6 (0.0471 h −1 ). The photocurrent response and electrochemical impedance spectroscopy (EIS) reveal that the Z-scheme heterojunction facilitates the separation of photogenerated charge carriers. Electron spin resonance (ESR) and radical trapping experiments demonstrate the pivotal roles of holes (h + ), superoxide (·O₂ - ), and singlet oxygen ( 1 O₂) in the catalytic degradation process. The results provide insights into the design of high-performance 2D/2D Z-scheme photocatalysts and a fundamental framework for further enhancement.
研究领域:
材料科学
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环境科学
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高影响因子
Inorganic Chemistry Frontiers
·
2020
·Vol. 8
·期 5
·1154-1165
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IF 5.958
Kunqiao Li,Wanbao Wu,Yanqiu Jiang,Zhe Wang,Xing Liu,Junzhuo Li,Debin Xia,Xianzhu Xu,Jizhuang Fan,Kaifeng Lin
The Z-scheme photocatalytic system has great potential in solar energy conservation with simultaneous wide light-absorption range, efficient electron–hole pair separation and strong redox ability. Herein, a direct Z-scheme g-C3N4/MoO3 photocatalytic composite with oxygen vacancies is successfully fabricated via a facile in situ method of a one-pot pyrolysis strategy. The as-prepared g-C3N4/MoO3 possesses a porous architecture with increased specific surface area. The existence of an oxygen vacancy in MoO3 is verified by XPS, UV-DRS analysis and electrochemical measurements. The g-C3N4/MoO3 exhibits superior visible-light photocatalytic performance for water splitting, as evidenced by an about 17-fold (20.52 μmol h−1) increase in the rate of H2 evolution relative to pristine C3N4 (1.23 μmol h−1). According to the characterization results and boosted photocatalytic performance, the migration and separation of photoinduced charge carriers in g-C3N4/MoO3 follows a possible mechanism based on a Z-scheme photocatalytic system constructed by the oxygen vacancies. The O-vacancy functions as the recombination and storage center for fast charge transfer through two components. The combined effect of defective MoO3 and a Z-scheme interfacial heterojunction has achieved greatly enhanced photocatalytic performance. This work demonstrates the facilitation effect of an effective Z-scheme system involving oxygen vacancies on the charge transfer to enhance the photocatalytic activity for water splitting.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
Journal of Materials Chemistry A
·
2022
·Vol. 11
·期 1
·241-250
·
IF 14.511
Fanqi Luo,Mingyang Liu,Mang Zheng,Qi Li,Hong Wang,Jing Zhou,Yong Jiang,Yaoguang Yu,Baojiang Jiang
Realizing CO2 reduction with H2O oxidation on g-C3N4-based photocatalysts is quite promising yet challenging. Herein, an efficient direct Z-scheme heterostructure of ultrathin CsPbBr3/g-C3N4 nanosheets is fabricated via a simple electrostatic self-assembly process, resulting in an effective photocatalytic reduction of CO2 to CH4 (184.0 μmol g−1) and CO (105.2 μmol g−1) with oxidation of H2O under AM 1.5G irradiation. Notably, in situ X-ray photoelectron spectroscopy (XPS) analysis demonstrated that a direct Z-scheme charge transfer mechanism at the CsPbBr3 and g-C3N4 interface is enabled, thereby achieving efficient charge separation and high redox potentials to drive photocatalytic CO2 reduction and H2O oxidation synchronously. Isotopic labelling experiments revealed that the adsorbed water is activated to release H atoms and eventually assists the CO2 reduction. Theoretical calculations further revealed that the p orbitals of Pb atoms hybridize with the 2π* orbitals of CO2 molecules, strengthening the affinity of CO2 and weakening the binding strength. Moreover, overlapping between Pb p orbitals and 5σ orbitals of CO molecules promote the protonation of CO* intermediates. This work provides an in-depth understanding and guidance for constructing high-efficiency catalysts for CO2 reduction with H2O oxidation.
研究领域:
材料科学
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环境科学
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化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）