APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Yandong Xu,Mengxia Guo,Chengjun Ge,Ping Zhang,Wen Xu,Linlin Zhang,Shihao Zhou,Jianjun Liao
To facilitate the activation of peroxymonosulfate, it is useful to simultaneously tune the coordination environment of the single-atom catalyst and develop a structure that effectively exposes the active site. In this study, we used a pre-assembly calcination method to prepare a structure composed of Cu single atoms on O-doped g-C 3 N 4 nanosheets (5Cu-OCN), and studied how this structure can effectively activate PMS under visible light catalysis. Compared to the g-C 3 N 4 , the 5Cu-OCN exhibits significantly improved PMS activation effect. Cu single atoms play an important role in catalyzing PMS activation and removing carbamazepine from solution, and explain the contribution of photo generated electrons and holes in enhancing the performance of catalysts in PMS activation. Furthermore, the constructive cooperation of 5Cu-OCN photocatalysts by PMS activation and photocatalysis has been shown to be useful in real aqueous systems. The results indicate that the main pathway for the generation of 1 O 2 is through the 5Cu-OCN photocatalytic process to promote PMS activation. In addition, the active reaction species involved in the degradation of carbamazepine were identified. This study provides an efficient copper monoatomic catalyst that can react to visible light for 1 O 2 based advanced oxidation processes.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2022
·
IF 4.331
Zhenyu Zhao,Xuting Wang,Shifu Wang,Zuoyi Xiao,Shangru Zhai,Jiliang Ma,Xiaoli Dong,Haodong Sun,Qingda An
The development of g-C3N4-based photocatalysts with abundant active sites is of great significance for photocatalytic reactions. Herein, a smart and robust strategy was presented to fabricate three-dimensional (3D) g-C3N4 nanosheet-coated alginate-based hierarchical porous carbon (g-C3N4@HPC), including coating melamine on calcium alginate (CA) hydrogel beads, freeze-drying hydrogel beads as well as pyrolysis at high temperatures. The resulting photocatalyst possessed a significantly high surface area and a large amount of interconnected macropores compared with porous carbon without the melamine coating. The unique structural features could effectively inhibit the curling and agglomeration of g-C3N4 nanosheets, provide abundant photocatalytic active sites, and promote mass diffusion. Therefore, the g-C3N4@HPC composite exhibited remarkable photocatalytic activity and outstanding stability toward the photoreduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) by NaBH4 under natural sunlight and simulated visible-light irradiation (λ > 420 nm) using a 300 W xenon lamp. Moreover, the mechanism toward the photocatalytic reaction was extensively studied by quenching experiments and electron spin resonance (ESR) experiments. The results showed that active hydrogen species were able to be achieved by following a dual-channel pathway in the NaBH4 system, which included photocatalytic reduction of H+ ions and photocatalytic oxidation of BH4– ions. This work not only opens up a new way to design efficient photocatalysts for various reactions but also provides a reference for an in-depth study of the photoreduction mechanism.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Xiuyang Zou,Meisheng Li,Huifang Xiao,Shouyong Zhou,Chenglung Chen,Yijiang Zhao
The complex transport mechanism of water and ions in the membrane hinders the design of free standing membranes. The mechanism of the mass transport characteristics of traditional nanofiltration membranes is no longer applicable to free standing membranes due to the change of the driving force in the membrane. In this study, the vacuum filtration of the g-C 3 N 4 suspension was simulated to form a free standing membrane model for the first time by using the molecular dynamics (MD) simulations. In the nanochannels formed by the g-C 3 N 4 nanosheets , the water molecules rapidly penetrated across the free standing membrane due to ultra-low friction. On the other hand, the hydrated Na + and Mg 2+ ions needed energy to partially dehydrate and penetrate across the free standing membrane. Moreover, the MD simulations indicated that the speed of Mg 2+ ions penetrating across the g-C 3 N 4 nanochannels was lower than that of Na + ions. Combined with the computational works, salt retention experiments were conducted to demonstrate the correctness of the proposed model. Further, the developed membranes exhibited excellent non-swelling stability and antibacterial activity in aqueous solutions. The g-C 3 N 4 free standing membranes prepared in this study can effectively realize the separation of monovalent and divalent ions, accompanied with high permeability.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 99
·96861-96869
·
IF 3.289
Lei Shi,Jinling Gou,Lin Liang,Fangxiao Wang,Jianmin Sun
A g-C3N4/Ag2WO4 composite photocatalyst was synthesized via a simple co-precipitation method at room temperature and was thoroughly characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, UV-visible diffuse reflectance spectroscopy and photoluminescence spectroscopy. The characterization results indicated that upon depositing Ag2WO4 onto the surface of g-C3N4 its morphology changed from primary rod-like particles to globular nanoparticles and its phase changed from α-type to β-type Ag2WO4. When the composite was used as the catalyst in the photodegradation of Rhodamine B, 40%-g-C3N4/Ag2WO4 exhibited the highest photocatalytic activity with its rate constant was about 10.8 times larger than that of pure g-C3N4 and 3.12 times larger than that of bare Ag2WO4. The enhanced photocatalytic activity can be attributed to the complementary potentials of the conduction bands and valence bands of g-C3N4 and Ag2WO4, which could not only realize the effective separation of photoinduced electron and hole pairs, but also retained the catalysts high stability and photocatalytic performance even after five recycles. Furthermore, a possible photocatalytic mechanism for the degradation of RhB over the g-C3N4/Ag2WO4 composite was proposed according to the results of active species quenching experiments.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2018
·
IF 3.927
Yuqi Cui,Xinyi Zhang,Huixuan Zhang,Qingfeng Cheng,Xiuwen Cheng
The application of semiconductor photocatalysts in wastewater treatment has received increasingly attentions because of its potential utilization of solar energy. In this study, a novel visible-light-driven (VLD) BiOCOOH/g-C 3 N 4 composite photocatalyst was successful synthesized by a facile hydrothermal method. Afterwards, physicochemical properties of the resulting samples were investigated through X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) surface areas, UV–visible diffuse reflectance spectroscopy (UV–vis DRS), transient photocurrent density, Mott-Schottky (M−S) and electrochemical impedance spectroscopy (EIS) measurement. Furthermore, the visible light photocatalytic (PC) performance was evaluated through the degradation of amido black 10B dye. All results indicated that the combination of g-C 3 N 4 and BiOCOOH could exhibited greatly visible light absorbance and photo-generated charge separation efficiency, thereby resulting in the enhanced PC performance of BiOCOOH/g-C 3 N 4 composite photocatalyst. The optimal Bi/C molar rate in BiOCOOH/g-C 3 N 4 composite was determined to be 1/1, and the corresponding photodegradation rate for amido black 10B was 0.01794 min −1 , which was nearly 2.19 and 5.73 folds higher than that of pure g-C3N4 and BiOCOOH. The possible mechanism of the PC reaction was also discussed in detail. Furthermore, BiOCOOH/g-C 3 N 4 composite photocatalyst performed good reusability and stability even after four recycle utilization.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Sustainable Energy & Fuels
·
2024
·Vol. 8
·期 13
·2889-2899
·
IF 5
Jiaqi Wang,Hongyang Huo,Guozhe Sui,Shuang Meng,Dongxuan Guo,Shanshan Fu,Dantong Zhang,Xue Yang,Jinlong Li
The development of visible-light-active photocatalysts with high performance has been regarded as a promising way to address environmental wastewater issues. In this work, a highly efficient g-C3N4/CdS/TiO2 ternary Z-type heterojunction photocatalyst with a hollow structure has been fabricated using a step-by-step self-assembly strategy, which demonstrates excellent photocatalytic performance under visible light and removes various water-soluble organic pollutants effectively. The photocatalytic degradation efficiency of 20-g-C3N4/CdS/TiO2-10 against rhodamine B (RhB) is found to be 29.8 times higher than that of the pristine g-C3N4 within 90 minutes of visible light irradiation attributed to the active species of ˙O2− and h+. Liquid chromatography mass spectrometry results suggest that the degradation pathway of RhB involves main steps such as N-de-ethylation, chromophore cleavage, ring opening, and mineralization. A series of characterization analyses, combined with the observed enhanced photocatalytic performance, indicate that the g-C3N4/CdS/TiO2 ternary heterojunction benefits from the rapid transport and separation of photogenerated carriers facilitated by the formation of a heterointerface. Furthermore, the g-C3N4/CdS/TiO2 ternary heterojunction exhibits favorable stability, with 88.1% degradation efficiency after five cycles of degradation experiments. This work provides novel insights into the preparation and application of ternary heterojunctions with superior photocatalytic performance for eliminating organic pollutants from wastewater.
研究领域:
环境科学
·
材料科学
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DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2022
·Vol. 24
·期 12
·7521-7530
·
IF 3.945
Qixiao Gai,Shoutian Ren,Xiaochun Zheng,Wenjun Liu,Quanli Dong
Low-cost and high-abundance Cu nanostructures are potential near-infrared (NIR) surface plasmonic resonance (SPR) photosensitizers for carbon nitride (C3N4) photocatalysts, but their low activity and stability need to be improved. In this article, doping S into C3N4 (S-C3N4) creates anchoring sites for photo-deposited Cu nanoparticles (NPs), and the spontaneous construction of S-Cu bonds is realized between S-C3N4 and Cu NPs. The optimal hydrogen evolution rate of 1.64 mmol g−1 h−1 is obtained for S-C3N4–Cu, which is 5.5, 4.6 and 1.7 times that of pure C3N4, S-C3N4 and S-C3N4–Cu, respectively. With further loading of a Pt co-catalyst to confirm the role of Cu NPs and improve the photocatalytic activity of the SCN–Cu, the photocatalytic rate can reach up to 14.34 mmol g−1 h−1. Due to the NIR SPR effect of Cu NPs, the apparent quantum efficiency (AQE) of S-C3N4–Cu at 600 and 765 nm is 2.02% and 0.47%, respectively. The enhanced photocatalytic performance of S-C3N4–Cu compared with C3N4–Cu is mainly due to the introduced S–Cu bonds that improve the injection rate of hot electrons. This solution provides a simple and efficient interface optimization strategy for the construction of efficient NIR-driven photocatalysts.
研究领域:
材料科学
·
光催化
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Quanfeng Xing,Min Zhang,Xiuquan Xu,Bo Zhang,Yun Duan,Yi Wei,Jiahui Wang,Mingyang Li
Previous studies have proved that the promoted interactions with bacteria was closely responsible for the improved inactivation efficiency of photocatalysts. Herein, for the first time, the cationic polymer polyethyleneimine (PEI) grafted O-doped g-C 3 N 4 (denoted as PEI/OCN) was successfully fabricated by combination one-pot thermal-polymerization and subsequent covalent cross-linking reaction. Benefiting from the synergistic effect of O-doping and PEI-grafting, the obtained PEI/OCN possessed an extended and intensive visible light response, accelerated photogenerated charge transport, good hydrophilicity as well as enough electrostatic adhesion to bacteria. As a result, PEI/OCN exhibited a dramatically boosted reactive oxygen species (ROS) generation and outstanding rapid photocatalytic bactericidal capability, achieving 7.0 log CFU mL −1 inactivation efficiency of Escherichia coli ( E. coli ) within 30 min visible light exposure. Radical trapping and electron spin resonance (ESR) experiments revealed that superoxide radicals ( • O 2 − ) were crucially dominated the superior photocatalytic disinfection activity. Overall, the presented work provided a rationally designing of novel metal-free g-C 3 N 4 -based photocatalysts for efficient elimination of bacterial contaminations.
研究领域:
环境科学
·
材料科学
·
微生物学
✓ 已验证
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Fengyun Su,Mengzhen Tian,Hailong Cao,Zhishuai Wang,Qiang Zhao,Haiquan Xie,Yezhen Zhang,Xiaoli Jin,Xin Li,Zhengdao Li
Semiconductor-based photocatalytic water splitting enables the conversion of abundant solar energy to green and renewable hydrogen energy. Graphitic carbon nitride (g-C 3 N 4 ) is synthesized using a straightforward method, demonstrating stable physicochemical properties and possessing an optimal bandgap, thus positioning it as a promising photocatalyst in the realm of environmental sustainability. Oxygen vacancies are extensively employed to modulate light absorption and surface properties of metal-oxide semiconductors. In this study, g-C 3 N 4 nanosheets were coupled with oxygen-deficient tungsten trioxide (WO 3-x ) to form heterojunction photocatalysts ( X -WOCN). Comprehensive material characterization results demonstrated that the constructed heterojunction extended the visible light absorption range, improved photogenerated electron-hole separation efficiency, and thus augmented photocatalytic activity . Notably, the optimum hydrogen evolution rate of 6 %-WOCN was enhanced by 5.4-fold compared to that of g-C 3 N 4 . Furthermore, we propose a Z-scheme heterojunction charge separation mechanism mediated by oxygen defects and support this mechanism through detection of surface-active substances •O 2 − and •OH. This study offers novel propositions into the function of oxygen defects in facilitating charge separation within Z-scheme heterojunction.
研究领域:
光催化
·
材料化学
·
能源科学
·
半导体物理
·
环境可持续性
·
纳米材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Nannan Wang,Bonan Hao,Hao Chen,Rongkang Zheng,Baojie Chen,Shihong Kuang,Xiaodong Chen,Lifeng Cui
Developing a cost-effective, efficient, and facile prepared electrocatalyst for oxygen reduction (ORR) and evolution reaction (OER) is critical for a range of renewable energy technologies. Herein, we report unique Co 4 N nanoparticles loading on g-C 3 N 4 nanotubes (Co 4 N@CNNT) bifunctional electrocatalyst for OER and ORR by an in-situ method. Highly dispersed Co 4 N nanoparticles as the active sites gather at the top of the g-C 3 N 4 nanotube (CNNT), while the six-fold cavities from smooth CNNT with an outer diameter of 48 nm and an inner diameter of 22 nm act as anchor sites to preferentially coordinate with the active sites. Benefiting from the distinctive structure features, the intrinsic metallic Co 4 N@CNNT exhibits high electrocatalytic performances. Electrochemistry studies show that an onset potential of 0.94 V and a half-wave potential of 0.86 V of Co 4 N@CNNT are obtained that are superior to Pt/C catalyst. A low overpotential of 285 mV at an anodic current density of 10 mA cm −2 during the OER process is obtained that is superior to the IrO 2 catalyst; and lower Tafel plot and good durability are also observed. Our findings provide a new strategy for the fabrication of an efficient bifunctional electrocatalyst for OER and ORR.
研究领域:
材料科学
·
电化学
·
可再生能源技术
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 25
·12217-12228
·
IF 3.925
Xiaoying Yuan,Yue Leng,Changlong Fang,Kangqi Gao,Chenyu Liu,Jianjun Song,Yingshu Guo
Tetracycline hydrochloride (TC) is a typical refractory organic pollutant, and is frequently detected in different water environments, which will increase microbial drug resistance, destroy ecosystems and threaten human health. It is urgent to develop a simple and effective catalyst for TC removal. In this paper, a facile two-step calcination method was used to prepare a LaCoO3/g-C3N4 composite catalyst with high activity and high stability for PMS activation to degrade TC. Various characterization results confirmed that the LaCoO3/g-C3N4 composite catalyst possessed smaller particle size, higher stability and faster electronic transmission ability. Benefiting from the synergistic effect between LaCoO3 and g-C3N4, the LaCoO3/g-C3N4 catalyst showed high activity for PMS activation to degrade different antibiotics. Furthermore, the results of the quenching experiments and the electron paramagnetic resonance (EPR) tests showed that the generated SO4˙− and 1O2 radicals during the PMS activation process played a key role in pollutant degradation. The effect of different reaction conditions (including pH, temperature, PMS concentration, catalyst dosage and different anions) on the performance of the catalyst was also investigated. The catalyst cycle evaluation experiments showed that the LaCoO3/g-C3N4 composite catalyst has high stability and reusability. The phytotoxicity evaluation based on seed germination experiments indicated that the LaCoO3/g-C3N4 composite catalyst system can effectively reduce the toxicity of antibiotics.
研究领域:
环境科学
·
材料科学
·
生物学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 33
·19169-19177
·
IF 3.119
Biao Zhou,Bo Yang,Muhammad Waqas,Ke Xiao,Caizhen Zhu,Ling Wu
Constructing a 0D/3D p–n heterojunction is a feasible strategy for accelerating photo-induced charge separation and promoting photocatalytic H2 production. In this study, a 0D/3D MoS2/g-C3N4 (0D/3D-MCN) photocatalyst with a p–n heterojunction was prepared via a facile light-assisted deposition procedure, and the 3D spongy-like g-C3N4 (3D-CN) was synthesized through simple thermolysis of NH4Cl and melamine mixture. For comparison, 2D-MoS2 nanosheets were also embedded in 3D-CN by a solution impregnation method to synthesize a 2D/3D-MCN photocatalyst. As a result, the as-prepared 0D/3D-MCN-3.5% composite containing 3.5 wt% 0D-MoS2 QDs exhibited the highest photocatalytic H2 evolution rate of 817.1 μmol h−1 g−1, which was 1.9 and 19.4 times higher than that of 2D/3D-MCN-5% (containing 5 wt% 2D-MoS2 nanosheets) and 3D-CN, respectively. The results of XPS and electrochemical tests confirmed that a p–n heterojunction was formed in the 0D/3D-MCN-3.5% composite, which could accelerate the electron and hole movement in the opposite direction and retard their recombination; however, it was not found in 2D/3D-MCN-5%. This study revealed the relationship among the morphologies of MoS2 using g-C3N4 as a substrate, the formation of a p–n heterojunction, and the H2 evolution activity; and provided further insights into fabricating a 3D g-C3N4-based photocatalyst with a p–n heterojunction for photocatalytic H2 evolution.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）