SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Shuai Wang,Jirong Long,Tian Jiang,Li Shao,Dan Li,Xianchuan Xie,Feigao Xu
Magnetic Fe 3 O 4 /CeO 2 /g-C 3 N 4 (FCG) composites with a visible-light response were successfully synthesized and characterized as a heterogeneous Fenton-like catalyst for tetracycline hydrochloride (TCH) degradation. The optimal mass ratio, pH value, catalyst addition, H 2 O 2 concentration, and temperature were explored. Photodegradation studies showed the best activity when the mass ratio of the composite was 1:0.75:0.75 (F 1 C 0.75 G 0.75 ) and the removal rate of TCH by F 1 C 0.75 G 0.75 reached 96.63% after 180 min. The first order kinetic constant of the reaction system was 0.0533 min −1 . According to the test of free radical scavenger and metal leaching tests, the Fenton-like degradation of TCH by F 1 C 0.75 G 0.75 composite was analyzed. g-C 3 N 4 effectively reduced the leaching of Fe and the location where TCH was attacked by hydroxyl radicals was mainly on the surface of the catalyst. The reusability of the F 1 C 0.75 G 0.75 composites was also studied after five cycles.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Jianhua Sha,Lulu Li,Zexiu An,Maoxia He,Haiyan Yu,Yao Wang,Baoyu Gao,Shiping Xu
Coexistence of heavy metals usually shows great impact on antibiotics removal. In this study, we firstly reported that Cu 2+ shows diametrically opposite effect on adsorption-photodegradation of sulfamerazine (SMZ) and ciprofloxacin (CIP) in g-C 3 N 4 /visible light system. Cu 2+ can greatly promote CIP adsorption, but showed negligible impact on its degradation, whereas, no obvious influence on SMZ adsorption was recorded, but strong inhibition to its photodegradation was observed. With help of several spectroscopy approaches and DFT calculation, functional mechanism of Cu 2+ on the adsorption-photodegradation of SMZ and CIP was proposed. The main reasons for their different behaviors were found to be their distinct surface charge, spatial structure, electron distribution and complexation with Cu 2+ . Among them, effect of complexation played the most important role in depressing the reactivity of antibiotics during photodegradation . Aiming at retarding this inhibition, an effective approach with idea of complexation replacement was proposed. This study indicated that interactions between antibiotics and heavy metals are very specific, and an appropriate treatment scheme should be given based on systematic study targeting at the specific pollution system.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2021
·
IF 5.909
Shaoru Liu,Weizi Zhang,Peng Zhu,Songlin Zuo,Haian Xia
The study reports a facile synthesis of Ag-g-C 3 N 4 /AC composites with highly photocatalytic activity and good adsorption capacity by an impregnation-thermal polycondensation process. The resulting Ag-g-C 3 N 4 /AC composites were used for treatment of different pollutants in water including Rhodamine B (RhB), Cr(VI) ions and pathogens . When the precursor mass ratio of urea and AC was 2:2, the resultant Ag-g-C 3 N 4 /AC catalyst showed the best photocatalytic performances. In particular, the composite photocatalysts exhibited highly bactericidal efficiency, which could reach 99.9% after 120 min of irradiation. The higher photocatalytic performances of Ag-g-C 3 N 4 /AC composites were attributed to the surface plasmon resonance (SPR) effect of Ag nanoparticles (NPs) together with the interfacial synergistic effects. Meanwhile, AC not only exhibited excellent adsorption capacity, but also decreased aggregation of g-C 3 N 4 , which could enhance the separation efficiency of photogenerated charge carriers. It was uncovered through Electron Spin Resonance (ESR) and radical scavenger experiments that • OH radicals, • O 2 − and h + participate in the RhB degradation under the visible light. This work shows that the high-efficient and stable Ag-g-C 3 N 4 /AC composites have a great potential in the treatment of organic pollutants , toxic heavy metals and pathogenic bacteria by adsorption/photocatalysis for practical water treatment .
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Long Huang,Linzhi Zuo,Zeyang He,Beibei Xiao,Hu Zhou,Shichuan Su,Yang Li,Ting Bian,Aihua Yuan
Rational incorporating transition metal into porous heteroatom-doped carbon is intensively investigated as an effective strategy to achieve high-performance and bifunctional requirements. Herein, we fabricated the hollow composite that CoFe alloy nanoparticles decorated on the tubular N-doped carbon (denoted as T-CoFe/NC) by soft-templating strategy. In order to effectively incorporate the CoFe alloy into nitrogen doped hollow carbon matrix, g-C 3 N 4 nanotubes were selected as the template to attain high contents of nitrogen doping for tubular carbon matrix. Meanwhile, the coordination effect between tannic acid and metal ions is utilized to limit the metal agglomeration in the process of pyrolysis. Consequently, the resultant catalyst shows an outstanding ORR activity with the half-wave potential of 0.86 V and outstanding stability with only a 2 mV decay after 10,000 cycles. T-CoFe/NC also displays comparable overpotential to the RuO 2 at 10 mA cm −2 . The high bifunctional electrocatalytic activity is attributed to the unique tubular structure and the combination of Co with Fe can optimize the interaction between the oxygenic species and metal surfaces, enhancing the catalytic activity. And T-CoFe/NC based zinc-air battery exhibits excellent power density, large capacity and good cycling stability.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Ziyi You,Xiaoyang Yue,Dainan Zhang,Jiajie Fan,Quanjun Xiang
In recent years, the use of quantum dots (QDs) cocatalysts to improve the hydrogen evolution activity from the water splitting of photocatalysts has become a popular research topic. Herein, we successfully prepared a novel 0 dimension/2 dimension (0D/2D) heterojunction nanocomposite (denoted Ag 2 S quantum dots (QDs)/g-C 3 N 4 ) with excellent photocatalytic performance by anchoring the Ag 2 S QDs cocatalyst on the surface of g-C 3 N 4 through a self-assembly strategy. Ag 2 S QDs with an average particle size of approximately 5.8 nm were uniformly and tightly modified on g-C 3 N 4 . The Ag 2 S QDs/g-C 3 N 4 composite with 0.5 wt% Ag 2 S QDs loading achieved the highest hydrogen evolution rate of 471.1 μmol·g −1 ·h −1 with an apparent quantum efficiency (AQE) of 1.48% at 405 nm. Such remarkable hydrogen evolution activity far exceeded that of undoped g-C 3 N 4 and Ag 2 S nanoparticles (NPs)/g-C 3 N 4 . Moreover, it was 2.04 times the activity of Pt/g-C 3 N 4 with Pt as the cocatalyst. The enhanced photocatalytic performance was attributed to the energy band broadening of Ag 2 S QDs caused by the quantum size effect and the convenient and effective charge transfer between g-C 3 N 4 and Ag 2 S QDs cocatalysts. The mechanism underlying the enhanced photocatalytic H 2 evolution activity was further proposed. This study demonstrates that semiconductor-based quantum dots are strong candidates for excellent cocatalysts in photocatalysis.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Jie Zhao,Bingzhang Li,Zongyang Liu,Danling Dai,Yuqi Li,Ronghui Shi,Hui Zhang
Sodium alginate (SA) aerogels have shown outstanding potential as regenerative adsorbent materials in the field of wastewater purification. Although SA aerogel adsorption has been demonstrated as a simple and resultful method for removing dyes, it has the limitation that it only transfers or concentrates dyes on the adsorbate, and does not actually degrade them. In this study, a three-dimensional (3D) MIL-125/g-C 3 N 4 /SA (CNTi-125@SA) composite aerogel with visible light photocatalytic activity was achieved for photocatalytic degradation of organic dyes, via in-situ growth, blending and freeze-drying strategy. The results demonstrate that CNTi-125@SA has high catalytic activity for the dyes rhodamine B (RhB), methylene blue (MB) and methyl orange (MO), and the degradation rate can reach up to 99.23%. Impressively, the composite aerogel exhibits excellent antibacterial ability, and the antibacterial rate can reach up to 100% against E. coli . In addition, the developed composite aerogel has excellent reusability and stability, and the degradation efficiency can still reach 85% after seven repeated tests. Owing to their high catalytic activity, excellent antibacterial properties and stability, the CNTi-125@SA composite aerogel can be potentially used in a wide range of dye wastewater purification.
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2020
·
IF 4.217
Yekun Zhu,Yun Zhang,Lili Cheng,Mohammed Ismael,Zhiyuan Feng,Ying Wu
The g-C 3 N 4 /NaNbO 3 photocatalyst was synthesized by simply calcining the mixture of NaNbO 3 and melamine. The synthesized composite exhibits high photocatalytic performance in the selective oxidation of 5-Hydroxymethylfurfural (HMF) to 5-formyl-2-furancarboxylic acid (FFCA) when using water as solvent. The structure and composition of g-C 3 N 4 /NaNbO 3 photocatalysts were characterized by TG, XRD, SEM, UV–Vis, FT-IR, and XPS methods, and the optical and electrochemical properties were investigated by EIS, PC, and PL techniques. O 2 − was inferred to be the primary active species in this process based on the active species trapping experiment. Heterostructure formation of g-C 3 N 4 /NaNbO 3 composites efficiently promoted the separation of photo-generated electron-hole pairs and accelerated the electron transfer rate, thus reduced the formation of OH, and sequentially improved the selectivity of FFCA. The highest HMF conversion of 35.8% with FFCA selectivity of 87.4% was achieved on C/N-59.6 photocatalyst under the irradiation of visible light. The possible mechanism and reaction route were also proposed.
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Shu-ao He,Wei Li,Xiao Wang,Qiong Ma,Min Li,Wei Xu,Xue-chuan Wang,Chen-hui Zhao
The two-dimensional (2D) g-C 3 N 4 has a wide application prospect in photocatalysis field due to its larger surface reactions, wider absorption of light and faster charge separation. However, the lack of active site of reduction leads to its poor hydrogen evolution reaction (HER) activity. In this work, the intermediate β-FeOOH was synthesized as a high-efficiency precious metal free co-catalyst in hydrogen production. Then, the g-C 3 N 4 -Fe 3 O 4 /β-FeOOH (CNFF-x,y, x = 1, 2 and 3, y denotes the reaction time (h)) photocatalyst based on p-n and Z-scheme heterojunction was constructed via a subsequent solvothermal process. The chemical composition, microtopography, crystallography, photochemical and electrochemical properties of the CNFF-x,y were analyzed by XRD, FI-IR, TEM, XPS and so on. The visible-light-driven (VLD) catalytic performance of CNFF-x,y heterojunction was evaluated by the hydrogen evolution reaction (HER). Results showed that CNFF-2,10 photocatalyst based on p-n (g-C 3 N 4 -Fe 3 O 4 ) and Z-scheme (Fe 3 O 4 /β-FeOOH) heterojunction presented the highest VLD catalytic HER activity (33.25 μmol g −1 h −1 ) at the absence of Pt co-catalyst after illumination for 6 h. It indicated that the effective introduction of Fe 3 O 4 /β-FeOOH nanoparticles (NPs) into g-C 3 N 4 to construct double-heterojunction (g-C 3 N 4 -Fe 3 O 4 /β-FeOOH) could greatly broaden the light response property and inhibit the recombination of photo-induced carriers, exhibiting enhanced HER activity. Meanwhile, this double-heterojunction photocatalyst presented robust photostability and reproducibility even been used several times. The findings of an intermediate β-FeOOH were put forward in this study will provide some new ideas for the research of HER.
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Biao Zhou,Muhammad Waqas,Bo Yang,Ke Xiao,Shengye Wang,Caizhen Zhu,Juying Li,Junmin Zhang
Synthesis of three-dimensional carbon nitride (g-C 3 N 4 ) structures is a promising but challenging task for effectively photocatalytic water splitting to generate H 2 . In this study, thin-shelled honeycomb-like structured g-C 3 N 4 (g-C 3 N 4 -TSH) was successfully synthesized via facile one-step co-pyrolysis of melamine/NH 4 Cl mixture and the morphology evolution mechanism was revealed systematically. By varying the ratios of melamine/NH 4 Cl precursor and thermal preparation temperatures, thin-shelled and thick-shelled honeycomb-like structured g-C 3 N 4 were obtained. Also, the key intermediate phases were identified by their structure characterizations, which revealed low-temperature phase transition of 1-D tube-like melamium/NH 4 Cl adduct, then transforming to 2-D multiple plate-like melamium/melon NH 4 Cl complex by sintering, and finally evolving to g-C 3 N 4 -TSH at high temperature. The final hierarchical structure has several beneficial features as hollow, mesoporous, ultrathin, and honeycomb-like form, which caused its high surface area, excellent mass transfer rate and good light absorption ability. As a result, the g-C 3 N 4 -TSH with Pt as co-catalyst showed remarkable photoactivity for H 2 evolution, with an apparent quantum efficiency of 9.86% at 420 ± 10 nm, which is superior to many reported modified g-C 3 N 4 . This study revealed the evolution mechanism of g-C 3 N 4 -TSH, which is conducive to design various dimension oriented g-C 3 N 4 structures via solid-state chemistry for photocatalytic H 2 evolution.
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2019
·Vol. 44
·期 5
·1795-1805
·
IF 3.069
Hao Liu,Xiaodong Zhu,Rui Han,Yuxue Dai,Yuanling Sun,Yanna Lin,Dandan Gao,Xueying Wang,Chuannan Luo
Study of the degradation mechanism of the Cu2O/g-C3N4 p–n heterojunction is very challenging and important for the preparation and practical applications of the g-C3N4 photocatalyst in controlling water pollution. Therefore, the Cu2O/g-C3N4 p–n heterojunction was designed and prepared successfully and the mechanism of enhanced visible-light photocatalytic activity was proposed. The morphology and structure of the synthesized materials were characterized by using SEM, TEM, FT-IR and XPS. And the optical and electrical properties of the materials were studied by measuring DRS, the photocurrent density and the Mott–Schottky curve. The results showed that the g-C3N4 photocatalyst is coated on the surface of Cu2O to form a tight heterojunction, which facilitates the separation and migration of photogenerated carriers, and the quantum yield of the Cu2O/g-C3N4 composite photocatalyst was 3–7 times higher than that of the single component. It has been shown that the built-in electric field formed at the heterojunction interface can effectively separate photogenerated electrons and holes. The photocatalytic performance of the material was evaluated by the photocatalytic degradation of tetracycline (TC) under visible light. The maximum degradation rate of Cu2O/g-C3N4 for TC could reach over 90% in 90 min, and the degradation rate of the single component is more than doubled. Simultaneously, the TOC tests monitored the mineralization of TC up to 83.4%, and the active substances in the reaction process were determined to be ˙O2− and h+ through free radical trap experiments and ESR tests. This work shows that the construction of an internal electric field has greatly improved the photocatalytic performance of g-C3N4. The Cu2O/g-C3N4 p–n heterojunction has good degradation ability toward tetracycline and is a good tetracycline-type wastewater treatment material.
✓ 已验证
产品关联
DOI
高影响因子
DYES AND PIGMENTS
·
2019
·
IF 4.018
Xiuquan Xu,Songmei Wang,Tongjie Hu,Xiaofeng Yu,Jiapeng Wang,Chao Jia
Co-doping has been proven to significantly enhance the photocatalytic performance of g-C 3 N 4 . Herein, Mn and O co-doped g-C 3 N 4 (Mn/O-CN) composites were constructed for the first time by a simple one-pot calcining route. The systematic characterization results of XRD , FT-IR, TEM-EDS, XPS and DRS revealed that the Mn and O elements were co-doped into the CN framework successfully as Mn 3+ / 4+ and n-π* conjugate forms, respectively. The as-prepared Mn/O-CN-2 achieved the highest visible-light-driven degradation rate constant of 0.0290 and 0.0267 min −1 for degradation of Malachite green (MG) and Amido black 10B (AB 10B), which were about 5.09 and 5.45 folds higher than that of pristine CN, respectively. The improved photocatalytic degradation property of Mn/O-CN were mainly benefited from the extended visible light utilization, the enlarged specific surface area, and the accelerated separation and transfer of photo-induced charge carriers, which were all induced by the synergistic effects of Mn and O co-doped. Finally, the active species capturing experiments proved that the superoxide radicals (·O 2 − ) and holes (h + ) acted as the predominant roles in the photocatalytic degradation process .
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2019
·Vol. 6
·期 4
·045514
·
IF 1.449
Jian Feng,Xiaosheng Yang,Rong Li,Xianjiong Yang,Hong Xu,Xiaolan Xi
Graphitic carbon nitride (g-C3N4) is the most stable allotrope of carbon nitride with a conjugated, two-dimensional polymer of s-triazine, which is considered as a promising photocatalyst in sustainable chemistry. The low surface area and quantum efficiency and fast electron-hole recombination of g-C3N4 restrict its practical application. The formation of two-dimensional mesoporous structure and the construction of proper semiconductor composites are two approaches to promote the effective separation of photogenerated exciton and reduce the charge transfer resistance, which is beneficial to restrain the recombination of exciton and improve photocatalytic hydrogen performance. In this work, two-dimensional mesoporous g-C3N4 nanosheets (MCNS) coupled with nonstoichiometric Zn-Cu-In-S (ZCIS) nanocrystals were synthesized by a hydrothermal method. The constructed ZCIS/MCNS composites possessed highly photocatalytic hydrogen evolution performance under visible light irradiation without any noble metal cocatalysts. The EIS spectra and transient photocurrent responses corroborated ZCIS/MCNS had higher separation and transportation efficiency of photogenerated electron and hole. The incorporation of ZCIS into MCNS reduced the charge transfer resistance and enhanced the charge transfer efficiency. As the result, the photocatalytic hydrogen evolution rate of ZCIS/MCNS was higher than those of pure ZCIS and MCNS. 10-0.2ZCIS/MCNS showed a highest H2 production rate of 12.3 μmol h−1 over 100 mg photocatalyst without cocatalysts. This work supplied a feasible strategy to construct ZCIS/MCNS composites for the exploitation of solar energy.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）