ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 32
·48522-48538
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IF 5.19
Wang Guanghui,Li Yingjie,Dai Jialing,Deng Nansheng
In this present study, a novel indirect Z-scheme TiO 2 @g-C 3 N 4 @biochar (TiO 2 @g-C 3 N 4 @BC) composite photocatalyst was successfully fabricated and characterized with SEM, TEM, EDS, XRD, FTIR, PL, XPS, and UV–vis DRS. The photocatalytic degradation behavior of ciprofloxacin (CIP) on the TiO 2 @g-C 3 N 4 @BC was evaluated under UV–vis and visible light irradiation, and the possible reaction mechanism of photocatalytic oxidation of CIP on the TiO 2 @g-C 3 N 4 @BC was explained. The TiO 2 @g-C 3 N 4 @BC composite photocatalyst exhibited stronger photocatalytic oxidation activity for CIP in comparison with TiO 2 , g-C 3 N 4 , TiO 2 @BC, and TiO 2 @g-C 3 N 4 . After 60 min of UV–vis and visible light irradiation, the photocatalytic removal efficiency of CIP by TiO 2 @g-C 3 N 4 @BC was 99.3 and 89.2%, respectively. The photocatalytic removal performance of CIP was affected by the initial concentration of CIP, catalyst dosage, and pH value. The composite photocatalyst presented excellent stability and reusability after five cycles. An indirect Z-scheme principle of the CIP photocatalytic oxidation reaction on TiO 2 @g-C 3 N 4 @BC was clearly proposed, and the whole process of photocatalytic degradation was the results of the interaction between CIP and reactive active species (·O 2 − , h + , and ·OH), of which ·O 2 − is the main active substance. Four CIP degradation pathways were proposed. This work may provide an effective strategy to remove antibiotics in wastewater.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2019
·Vol. 10
·期 1
·1
·
IF 4.034
Rui Geng,Juanjuan Yin,Jingxin Zhou,Tifeng Jiao,Yao Feng,Lexin Zhang,Yan Chen,Zhenhua Bai,Qiuming Peng
The construction of heterojunctions provides a promising strategy to improve photocatalytic hydrogen evolution. However, how to fabricate a nanoscale TiO2/g-C3N4heterostructure and hinder the aggregation of bulk g-C3N4using simple methods remains a challenge. In this work, we use a simple in situ construction method to design a heterojunction model based on molecular self-assembly, which uses a small molecule matrix for self-integration, including coordination donors (AgNO3), inorganic titanium source (Ti(SO4)2) and g-C3N4precursor (melamine). The self-assembled porous g-C3N4nanotube can hamper carrier aggregation and it provides numerous catalytic active sites, mainly via the coordination of Ag+ions. Meanwhile, the TiO2NPs are easily mineralized on the nanotube template in dispersive distribution to form a heterostructure via an N–Ti bond of protonation, which contributes to shortening the interfacial carrier transport, resulting in enhanced electron-hole pairs separation. Originating from all of the above synergistic effects, the obtained Ag/TiO2/g-C3N4heterogenous photocatalysts exhibit an enhanced H2evolution rate with excellent sustainability 20.6-fold-over pure g-C3N4. Our report provides a feasible and simple strategy to fabricate a nanoscale heterojunction incorporating g-C3N4, and has great potential in environmental protection and water splitting.Keywords:heterojunction;Ag/TiO2/g-C3N4;Co-assembly;hydrogen evolution
研究领域:
材料科学
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环境科学
·
光催化
✓ 已验证
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Yanhong Li,Qifeng Zhang,Yi Lu,Zhiting Song,Changjiang Wang,Dongshuo Li,Xiao Tang,Xianju Zhou
The photocatalytic degradation of tetracycline in aqueous solution is a typical heterogeneous reaction, and thus the design of efficient photocatalysts for tetracycline degradation should revolve the process features of heterogeneous reaction closely. In the present work, TiO 2 -P/ g -C 3 N 4 composites with abundant surface hydroxyls were prepared by coupled g -C 3 N 4 nanosheets with plasma treated TiO 2 (TiO 2 -P) nanoparticles . The resultant TiO 2 -P/ g -C 3 N 4 as photocatalysts showed higher activity for the degradation of tetracycline in aqueous solution than g -C 3 N 4 , TiO 2 , TiO 2 -P and TiO 2 / g -C 3 N 4 under visible light irradiation. The better activity of TiO 2 -P/ g -C 3 N 4 photocatalysts for tetracycline degradation could be ascribed to the good synergy between TiO 2 -P and g -C 3 N 4 . Specifically, due to the presence of surface hydroxyls on TiO 2 -P, the tetracycline adsorption activity, electrons-holes separation property as well as H 2 O 2 activating activity of TiO 2 -P/ g -C 3 N 4 during tetracycline degradation were improved. By integrating the property of g-C 3 N 4 photocatalyst in H 2 O 2 production, as well as the property of TiO 2 -P in activating H 2 O 2 into •OH and •O 2 - , efficient photo-Fenton degradation of tetracycline was achieved in the TiO 2 -P/ g -C 3 N 4 photocatalytic system. Our study on TiO 2 / g -C 3 N 4 composite photocatalyst provides helpful inspiration to design photocatalysts with high-activity for the photo-Fenton degradation of organic pollutants .
研究领域:
环境催化
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材料化学
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环境污染治理
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光化学
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纳米材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Bo Yu,Fanming Meng,Muhammad Wasim Khan,Rui Qin,Xingbin Liu
Traditional bulk photocatalysts often experience serious charge recombination and poor visible-light capturing, resulting in inefficient photocatalytic activity. However, proper nanostructure design usually helps to increase the activity of composite photocatalysts. Here, hollow TiO 2 @g-C 3 N 4 /Co 3 O 4 core-shell microspheres are first reported. The hollow structure of the heterostructured will directionally separate the photogenerated carriers, and the photogenerated holes transferred to the surface will be further captured by Co 3 O 4 to achieve an exposed oxidized surface. The novel multi-stage hollow microspheres can simultaneously achieve effective transfer of photogenerated carriers and extended light absorption. Benefiting from these structural and compositional characteristics, the optimized TiO 2 @g-C 3 N 4 /Co 3 O 4 nanospheres have excellent photodegradation activity for tetracycline and MO. Under simulated sunlight, the degradation rates of TC (10 mg/L) and MO (25 mg/L) at 60 min are 91.6% and 97.8%, respectively. At the same time, high activity is maintained after multiple cycles of testing. Possible transfer paths for photogenerated carriers have also been proposed. This work will provide more inspiration for the design of multi-stage hollow photocatalytic systems.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Lina Ma,Guohong Wang,Chuanjia Jiang,Helin Bao,Qingchuan Xu
Core-shell composites with titanium dioxide (TiO 2 ) hollow microsphere as the core and graphitic carbon nitride (g-C 3 N 4 ) as the shell were fabricated via a two-step self-assembly procedure with the assistance of ultrasonic dispersion. The as-prepared composite samples with different g-C 3 N 4 contents (0–20%) were thoroughly characterized and the photocatalytic activity was evaluated by the photocatalytic degradation of Rhodamine B (RhB) in aqueous solution under visible light. A g-C 3 N 4 layer of approximately 80 nm was successfully coated on the surface of TiO 2 hollow microspheres with a diameter of 1–3 μm, forming a heterostructure with close interfacial contact. The TiO 2 @g-C 3 N 4 composite exhibited significantly enhanced photocatalytic activity as compared with pure TiO 2 hollow microspheres. At an optimum weight ratio of g-C 3 N 4 to TiO 2 (15 wt.%), the photocatalytic activity of the composite sample was almost 3 times higher than that of reference TiO 2 hollow microspheres. Moreover, the results of recycling test indicated that the TiO 2 @g-C 3 N 4 composite had excellent stability. A possible photocatalytic reaction mechanism of TiO 2 @g-C 3 N 4 composite was proposed, in which superoxide radical anions played the major role in the oxidation of RhB, and the separation of photogenerated charge carriers across the heterostructure interface inhibited electron-hole recombination, thus enhancing the photocatalytic activity.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2018
·Vol. 25
·期 20
·20206-20216
·
IF 2.8
Wang Peifang,Guo Xiang,Rao Lei,Wang Chao,Guo Yong,Zhang Lixin
A TiO 2 /g-C 3 N 4 composite photocatalytic film was prepared by in situ synthesis method and its photocatalytic capability under weak-visible-light condition was studied. The co-precursor with different ratio of melamine and TiO 2 sol-gel precursor were treated using ultrasonic mixing, physical deposition, and co-sintering method to form the smooth, white-yellow, and compact TiO 2 /g-C 3 N 4 composite films. The prepared TiO 2 /g-C 3 N 4 materials were characterized by SEM, TEM, EDS, XRD, BET, VBXPS, and UV-vis diffuse reflectance spectra. The results of composite showed that TiO 2 and g-C 3 N 4 have close interfacial connections which are favorable to charge transfer between these two semiconductors with suitable band structure, g-C 3 N 4 retard the anatase-to-rutile phase transition of TiO 2 significantly, the specific surface area were increased with g-C 3 N 4 ratio raised. Under weak-light irradiation, composite films photocatalytic experiments exhibited RhB removal efficiency approaching 90% after three recycles. Powders suspension degradation experiments revealed the removal efficiency of TiO 2 /g-C 3 N 4 (90.8%) was higher than pure TiO 2 (52.1%) and slightly lower than pure g-C 3 N 4 (96.6%). By control experiment, the enhanced photocatalysis is ascribed to the combination of TiO 2 and g-C 3 N 4 , which not only produced thin films with greater stability but also formed heterojunctions that can be favorable to charge transfer between these two semiconductors with suitable band structure. This study presents the potential application of photocatalytic film in the wastewater treatment under weak-light situation.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Today Communications
·
2023
·
IF 3.8
Yuan Li,Huigui Zhang,Wenyao Qian,Yong Xia,Dongmei Li,Zhiqiang Guo
In recent years, the emerging S-scheme heterojunction photocatalyst has embodied great potential in promoting the research and application of photocatalytic technology. Herein, a new TiO 2 /g-C 3 N 4 S-scheme heterojunction photocatalyst (TCN-20) was constructed by decorating graphite-like carbon nitride on sea urchin-like TiO 2 microspheres with a large specific surface area and a mesoporous structure. TCN-20 has excellent optical absorption ability, effective photogenerated electron-hole pair separation and very high photocatalytic degradation activity in the simulated sunlight. The degradation rate of TCN-20 for Rhodamine B reaches 96.5 %, and the reaction rate constant is 4.98 and 4.52 times higher than that of pure TiO 2 and g-C 3 N 4 , respectively. Moreover, X-ray photoelectron spectra, Fermi level and band structure analyses as well as radical quenching experiments authenticate the S-scheme charge transfer mechanism of TCN-20. TCN-20 is an easy-to-prepare, non-toxic, inexpensive and promising S-scheme heterojunction photocatalyst with strong redox ability.
研究领域:
材料科学
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环境科学
·
光催化技术
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2023
·Vol. 13
·期 12
·8383-8393
·
IF 3.9
Yan Wang,Jingyu Xiu,Tao Gan,Haiming Zou,Feiyue Li
In this work, a visible light-driven La/TiO2@g-C3N4 photocatalyst was synthesized for the photodegradation of tetracycline hydrochloride (TCH) in the presence of peroxydisulfate (PDS) in an internal loop-lift reactor. The surface morphology and structure of La/TiO2@g-C3N4 have been characterized by XRD, SEM-EDS, FTIR, XPS, and UV/vis DRS. La/TiO2@g-C3N4 displays outstanding photocatalytic performance and reusability. After four reuse cycles of the vis/La/TiO2@g-C3N4/PDS system, the TCH degradation rate and efficiency still reached 0.083 min−1 and 97.68%, respectively. Reactive species in this system included free radicals SO4˙−, ˙OH, and ˙O2−, as well as non-radicals e−, and h+, as established from the results of chemical quenching experiments. Moreover, a mechanism of action of the vis/La/TiO2@g-C3N4/PDS system for TCH degradation was proposed. The acute toxicity of the reaction solution towards Photobacterium phosphoreum T3 spp. in the vis/La/TiO2@g-C3N4/PDS process increased during the first 60 min and then decreased, illustrating that vis/La/TiO2@g-C3N4/PDS provided an effective and safe method for the removal of TCH.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Junjie Wang,Zhihao Lu,Kun Gao,Xing Kang,Chengcheng Zhu,Furong Qiao,Haonan Chen,Zhuoyao Li,Wei Huang,Gang Lu
Photocatalytic reforming of ethanol provides an effective way to produce hydrogen energy using natural and nontoxic ethanol as raw material. Developing highly efficient catalysts is central to this field. Although traditional semiconductor/metal heterostructures (e.g., Rh/TiO2) can result in relatively high catalyst performance by promoting the separation of photoinduced hot carriers, it will still be highly promising to further improve the catalytic performance via a cost-effective and convenient method. In this study, we developed a highly efficient photocatalyst for ethanol reformation by preparing a ternary composite structure of Rh/TiO2/g-C3N4. Hydrogen is the main product, and the reaction rate could reach up to 27.5 mmol g–1 h–1, which is ∼1.41-fold higher than that of Rh/TiO2. The catalytic performance here is highly dependent on the wavelength of the light illumination. Moreover, the photocatalytic reforming of ethanol and production of hydrogen were also dependent on the Rh loading and g-C3N4:TiO2 ratio in Rh/TiO2/g-C3N4 composites as well as the ethanol content in the reaction system. The mechanism of the enhanced hydrogen production in Rh/TiO2/g-C3N4 is determined as the improvement in the separation of photoinduced hot carriers. This work provides an effective photocatalyst for ethanol reforming, largely expanding its application in the field of renewable energy and interface science.
研究领域:
可再生能源
·
界面科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS RESEARCH BULLETIN
·
2019
·
IF 3.355
Bo Yu,Fanming Meng,Muhammad Wasim Khan,Rui Qin,Xingbin Liu
Herein, TiO 2 /g-C 3 N 4 /Ag (TCA) composites were successfully fabricated by a simple two-step method and wet chemical reduction. Titanium isopropoxide and melamine were used as precursors to prepare TiO 2 /g-C 3 N 4 heterojunction composites by simple stirring and calcining. Then, different mass fractions of AgNPs were decorated on the surface of the above composites by wet chemical reduction to obtain a sequence of TiO 2 /g-C 3 N 4 /Ag (TCA) composites. TCA composites were analyzed by XRD, TEM, HRTEM, EDS, XPS, BET, Raman spectroscopy, PL spectrum and UV–vis diffuse reflectance spectrum. The results showed that TCA composites had remarkable enhancement in the separation of photogenerated carriers and the utilization of light, which was as result of the coordination of the three components. For photodegradation of RhB or phenol under simulated sunlight, TCA-1 samples revealed the best photocatalytic degradation performance, and the corresponding degradation rates were 91.4% at 60 min and 90.0% at 120 min, respectively. Moreover, TCA-1 composites maintained superior degradation performance after reusability tests, indicating that TCA-1 composites had excellent photochemical stability. For experimental results, a possible photodegradation mechanism of TCA composites was also proposed.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2023
·
IF 10.9
Songyu Yang,Kailin Wang,Qiao Chen,Yan Wu
S-scheme heterostructure photocatalysts can achieve highly efficient solar energy utilization. Here, single-atom Ni species were deposited onto TiO 2 /g-C 3 N 4 (TCN) composite photocatalyst with an S-scheme heterojunction for highly efficient photocatalytic water splitting to produce hydrogen. Under solar irradiation, it realized the hydrogen production activity of 134 µmol g –1 h –1 , about 5 times higher than the TCN without atomic Ni. In-situ Kelvin probe force microscopy characterization and the density functional calculation certify that by forming the S-scheme heterojunction, the photo-excited electrons from the TiO 2 combine with the photogenerated holes at the coupled g-C 3 N 4 driven by a built-in electric field. More importantly, the single-atom Ni species stabilized the photogenerated electrons from the g-C 3 N 4 could effectively enhance the charge separation between the holes on the valence band of TiO 2 and electrons at the conduction band of g-C 3 N 4 . Meanwhile, the Ni atoms act as the surface catalytic centers for the water reduction reaction, which greatly improves the reactivity of the photocatalyst. The present work provides a new approach for developing noble metal-free heterojunctions for high-efficiency photocatalysis.
研究领域:
材料科学
·
能源化学
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2022
·
IF 3.754
Zhengdong Zhang,Xingyu Chen,Shanhua Chen,Qi Dong,Xinyi Zhang,Ao Jiang,Dafu Zhang,Yuli Di,Taishan Li
A Z-scheme TiO 2 /g-C 3 N 4 heterostructure system was used to activate peroxymonosulfate (PMS) for the photocatalytic degradation of Rhodamine B (RhB). The Z-scheme TiO 2 /g-C 3 N 4 heterojunction photocatalysts were successfully synthesized by using a simple impregnation method. The structure and surface morphology of the samples were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), X-Ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The optical and electrochemical properties were characterized by UV–vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL) electrochemical impedance spectroscopy (EIS).The results indicated that the Z-scheme heterojunction between TiO 2 and g-C 3 N 4 was successful established and the optimal photocatalytic activity was achieved when the mass ratio of TiO 2 to g-C 3 N 4 is 10:1. The degradation rate of RhB (20 mg/L, 50 mL) was 82.79% within 120 min simulated sunlight irradiation. After adding PMS to 10% TiO 2 /g-C 3 N 4 heterojunction photocatalysts , the reaction rate constant (k) of the TiO 2 /g-C 3 N 4 -PMS system is about 11.39 times as large as that with 10% TiO 2 /g-C 3 N 4 system. Moreover, the free radical trapping experiments results demonstrated that h + and SO 4 − · were the main active species in the TiO 2 /g-C 3 N 4 -PMS system.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
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