JOURNAL OF SOLID STATE CHEMISTRY
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2023
·
IF 3.3
Gang Liu,Sheng Xu,Wenting Li,Zhenxi Wang,Meng Cao,Jinlong Cui,Xinde Jiang,Zhengqiu Li
In order to improve the visible light catalytic activity of TiO 2 , the TiO 2 @g-C 3 N 4 (TCN) composite catalysts with three-dimensional porous structure and rich active sites were prepared by hydrothermal method and calcination method orderly. The synthesized TCN composites microstructures were thoroughly characterized and their performance for the photocatalytic degradation of organic dyes was investigated. The results show that the prepared composites formed the heterojunctions with a core-shell structure, which can effectively broaden the absorption spectrum of TiO 2 to visible light region. In the degradation experiments, the TCN composites exhibited excellent photocatalytic degradation effect on organic dyes, which can reach 99.65% under visible light irradiation for 2 h. The strong acid condition was benefit to the catalytic process. After five cycles of testing, the degradation efficiency of organic dyes can still maintain at 95.62% level, which indicate that the TCN composites had excellent visible light catalytic activity and reusability.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
DALTON TRANSACTIONS
·
2019
·Vol. 48
·期 10
·3486-3495
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IF 4.052
Juying Lei,Bin Chen,Weijia Lv,Liang Zhou,Lingzhi Wang,Yongdi Liu,Jinlong Zhang
A TiO2/g-C3N4 composite photocatalyst with an inverse opal structure and heterojunction has been successfully prepared by a relatively facile approach. The catalyst was characterized by a combination of XRD, SEM, HRTEM, XPS, PL, EIS and DRS techniques and applied for the photocatalytic degradation of organic pollutants represented by Rhodamine B, phenol and levofloxacin. The results of RhB degradation showed that the rate constant of inverse opal TiO2/g-C3N4 with the best compound ratio is 0.184 min−1, which is 2.7 times faster than that of normal TiO2/g-C3N4 and 4.2 times faster than that of inverse opal TiO2. The enhancement of photocatalytic activity may be attributed to the matched overlapping band structure and the interaction between inverse opal g-C3N4 and TiO2. The inverse opal structure of g-C3N4 has improved the optical absorption properties of g-C3N4 and the interaction between inverse opal g-C3N4 and TiO2 creates more interfaces for the efficient transfer of photogenerated electron–hole pairs to restrict the recombination, which was proved from the photoluminescence spectra (PL). Moreover, a possible photocatalytic mechanism has been tentatively proposed according to the experimental results. All in all, both the inverse opal structure and heterojunction construction play significant roles in the excellent photocatalytic degradation performance according to the mechanism investigation.
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
NANOTECHNOLOGY
·
2024
·Vol. 35
·期 49
·495704
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IF 2.9
Gang Xiao,Zishuai Wang,Yu Jin,Fengping Wang
The selective cleavage of lignin C–C bonds is a highly sought-after process with the goal of obtaining low-molecular-weight aromatic chemicals from renewable resources. However, it remains a challenging task to achieve under mild conditions. Photocatalysis is a potentially promising approach to address this issue, but the development of efficient photocatalysts is still in progress. In this study, we introduce the heterostructured TiO2@g-C3N4 photocatalyst for the development of a visible light photocatalytic procedure for the selective cleavage of lignin C–C bonds under mild conditions. The photocatalyst displays favourable visible light absorption, efficient charge separation efficiency, and promising reusability. A typical β–O–4 dimer model, 2-phenoxy-1-phenylethanol, was effectively (96.0% conversion) and selectively (95.0 selectivity) cleaved under visible light at ambient conditions. This photocatalytic procedure was also effective when subjected to solar irradiation or other lignin dimer models with β–O–4 or β-1 linkages. This reaction occurred through a Cβ-centred radical intermediate and a six-membered transition state with photogenerated holes as the primary active species. The Cα–OH oxidative dehydrogenation of the substrate could also take place but was a relatively minor route. This study provides a new photocatalytic procedure for visible-light-driven lignin valorisation and sheds light on the design of high-performance nanocomposite photocatalysts for C–C bond cleavage.
研究领域:
化学工程
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材料科学
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可再生能源
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DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2020
·
IF 4.872
Xiarong Zheng,Yuanqiong Liu,Xiaobin Liu,Qingbiao Li,Yanmei Zheng
A novel composite electrospun fiber with high photocatalytic efficiency, good stability, strong hydrophobicity, good pollution resistance, and easy separation and recovery was synthesized. The TiO 2 @g-C 3 N 4 (TCN) with special core-shell structure (5–10 nm shell) facilitated the separation of photogenerated electron-holes and had high photocatalytic performance. The poly (vinylidene fluoride) (PVDF) electrospun fiber immobilized with TCN was successfully fabricated (PVDF-TCN) with uniform distribution and size of nanofibers by using electrospinning, which was used for degrading tetracycline under visible-light irradiation (> 400 nm). A special rougher surface of electrospun fiber obtained by washing of sacrificial PVP increased the specific surface area, which became more conducive to the adhesion of the catalyst. The water contact angle and FTIR results demonstrated that the electrospun fiber became extremely hydrophilic after adding TCN catalyst, which could effectively mitigate the fiber pollution. The PVDF-TCN-0.2g electrospun fiber exhibited excellent photocatalytic performance and the degradation efficiency of tetracycline was up to 97% in 300 min under visible-light irradiation. The mechanism of PVDF-TCN electrospun fiber degradation of tetracycline in the photocatalytic process was also proposed. In addition, the PVDF-TCN-0.2g exhibited a stable activity after 4 cycles experiments since the degradation efficiency remained about 90%. Therefore, we believed this study provided a new strategy in catalyst immobilization and wastewater treatment.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
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IF 4.9
Ting-Ting Li,Meng-Meng Xie,Hong-Yang Wang,Jun-Sheng Wang,Jia-Horng Lin,Ching-Wen Lou
It is a challenge to effectively degrade phenanthrene (PHE) pollutants, which are widely present in aquatic environments, in order to reduce harm to humans and ecosystems. In this study, an S-scheme TiO 2 /g-C 3 N 4 photocatalytic system is constructed using 0D TiO 2 nanospheres and 2D g-C 3 N 4 nanosheets for the removal of PHE from water under sunlight irradiation. The effects of irradiation time, quality ratio of TiO 2 to g-C 3 N 4 , and cycle time on the performance of the TiO 2 /CN photocatalyst are investigated. The experimental results show that the ratio of TiO 2 to g-C 3 N 4 significantly affects the photocatalytic activity of the photocatalyst. Under the optimal ratio of TiO 2 to g-C 3 N 4 (50 % TiO 2 /CN), the apparent reaction rate constant for phenanthrene reached 0.00796 min −1 , which is 11.5 times higher than that of pure TiO 2 (0.00069 min −1 ). The tests of optical performance and photoelectrochemical properties further confirmed that the construction of the TiO 2 /g-C 3 N 4 S-type photocatalyst successfully enhanced the spatial separation efficiency of photogenerated carriers and ensured a continuous supply of energy during the redox reaction process. Converting highly toxic phenanthrene into a non-toxic green degradation product provides an practical strategy for the safe treatment of PHE in aqueous environments through the use of visible-light-driven heterojunction photocatalysts. Additionally, the data collected on phenanthrene degradation in this study will provide valuable references for developing degradation methods for other PAHs, such as naphthalene, anthracene, and pyrene.
研究领域:
环境科学
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材料科学
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光化学
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水处理
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DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2021
·
IF 3.764
Like Ouyang,Yan Zhang,Yuan Wang,Xinlong Wang,Shaojun Yuan
The coupled adsorption–photocatalytic oxidation process provides a great potential scenario to enhance the removal efficiency of arsenite contaminants by converting As(III) to As(V) and simultaneous adsorption. In this study, the boron-doped black TiO2/g-C3N4 nanocomposite is synthesized by combination of sol–gel and in situ decomposition-thermal polymerization methods as a photocatalyst for the photocatalytic oxidation and adsorption of As(III). Under dark conditions, the boron-doped samples (B-TiO2 and B-TiO2/g-C3N4) display an increase in the As(III) adsorption capacity by one order of magnitude up to circa 3.2 mg g–1 with an initial As(III) concentration of 2 mg L–1 at 298.15 K and pH 5. The adsorption kinetics of As(III) on B-TiO2/g-C3N4 conform to the pseudo-second-order kinetic model, revealing the chemical adsorption mechanism. Under visible light irradiation, the total arsenic removal capacity is substantially improved by 20% with a removal capacity of 3.9 mg g–1. The enhancement of arsenic adsorption is attributed to the chemical complexation and hydrogen bond, in which B–OH bonds play a dominant role. The photocatalytic oxidation mechanism of the as-synthesized B-TiO2/g-C3N4 is attributed to the synergism of superoxide radicals, hydroxyl radicals, and photogenerated holes.
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
NANOTECHNOLOGY
·
2018
·Vol. 29
·期 31
·315601
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IF 3.404
Gang Xiao,Shengnan Xu,Peifeng Li,Haijia Su
Heterostructured photocatalysts based on g-C3N4 and TiO2 represent a promising kind of photocatalyst in environmental fields, but the synthesis methods are always complex and not green. In the present paper, a facile and green one-step calcination procedure at lower temperature (450 °C) with the assistance of water is developed to synthesize a visible-light-active TiO2@g-C3N4 heterostructured photocatalyst, which shows higher visible-light-driven activity (k = 0.014 min−1) than pure g-C3N4 (k = 0.0036 min−1) and TiO2 (k = 0.0067 min−1) for methyl orange degradation. Excellent performance (over 90% conversion) was also observed for the removal of rhodamine B, phenol, and Cr(VI) under visible light. The heterostructured photocatalyst showed favorable reusability, preserving 86% of its activity after five successive cycles. A mechanism study demonstrates that the enhanced photocatalytic activity results from the efficient separation of the photo-generated charge carriers through the intimate interface between the two semiconductors based on their appropriate band structures and light-induced mechanism. The heterostructured photocatalyst will certainly find wide applications in the treatment of various toxic pollutants in wastewater using abundant solar energy. Furthermore, this facile and green procedure and the proposed synergistic mechanism will provide guidelines in designing other g-C3N4 based organic–inorganic composite photocatalysts for various applications.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
WATER AIR AND SOIL POLLUTION
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2023
·Vol. 234
·期 10
·1-14
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IF 2.9
Jiang Huize,Yang Jinge,Wang Xinxin,Wang Aihong,li Yuzhi,Wang Jinyu
The massive use of acetaminophen (APAP) poses a potential crisis for humans and the environment. In this paper, the degradation of APAP in aqueous solution was carried out using photocatalytic synergistic persulfate oxidation. To enhance the photocatalytic activity of g-C 3 N 4 and thus activate the persulfate (K 2 S 2 O 8 , PS) more effectively, the heterojunction photocatalyst TiO 2 /g-C 3 N 4 (TCN) was prepared by a hydrothermal method. The TCN-PS catalytic system showed a high efficiency for APAP degradation. When the amount of TCN and PS added was 0.6 g/L, the degradation rate of APAP at 10 mg/L was 78.3% after 60 min of illumination. Moreover, the TCN-PS catalytic system was effective in removing organic pollutants in acidic, neutral, and weakly alkaline environments. The radical quenching experiment results indicate that both sulfate radicals (SO 4 − •) and hydroxyl radicals (•OH) are involved in the degradation reaction. After five cycles, the TCN-PS catalytic system still has stable catalytic activity.
研究领域:
环境科学
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化学工程
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材料科学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
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IF 3.83
Bo Lv,Lili Lu,Xuefan Feng,Xiaoping Wu,Xiaoming Wang,Xiong Zou,Fuqin Zhang
Photocatalysis is one of the most promising ways to realize artificial photosynthesis. The biologically inspired photocatalysts with 3D flower-like structures have attracted much attention. In this study, an effective method for the synthesis of composite photocatalytic material, NH 4 TiOF 3 /TiO 2 /g-C 3 N 4 , with a 3D camellia-like structure, was developed. The 3D hierarchical structure of the composite material enabled multiple refractions and reflections of light within the catalyst, which greatly improved the efficiency of the sunlight harvesting. The combination of NH 4 TiOF 3 and TiO 2 also effectively reduced the electron-hole recombination in the g-C 3 N 4 . To evaluate its photocatalytic performance, the prepared nanostructured composite materials were tested for the water-splitting with simulated sunlight. It showed the hydrogen evolution at the rate of 3.6 mmol/g/h, which is 4.0 times faster than that from the pure g-C 3 N 4 . The composite materials exhibited excellent cycling stability. The detailed mechanism of the Z-scheme heterojunction was also discussed. The proposed synthesis route for the creation of 3D flower-like hierarchical composites provides a new effective technique for developing efficient, active, and stable composite photocatalysts for hydrogen production.
研究领域:
材料科学
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能源化学
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光催化
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2023
·Vol. 47
·期 17
·8170-8181
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IF 3.3
Shuanghui Liu,Changle Wang,Yao Song,Binglin Yan,Bing Ai,Kefeng Pan,Lipeng Zhang
The heterojunction structure of semiconductor photocatalysts is significant for making full use of their capabilities for organic molecules and dye degradation. In this paper, we present a heterogeneous junction composite fabricated with hybrid phase TiO2 and g-C3N4 for methylene blue (MB) removal through adsorption and photocatalytic degradation. The heterogeneous junction system was prepared by hydrothermal treatment with a subsequent pyrolysis process. The variation of the proportion and lattice structure of hybrid phase TiO2 in the synthesized catalysts was analyzed by refinement. Adsorption experiments showed that the maximum adsorption capacity of TiO2/g-C3N4 (1 : 10) was 1667 mg g−1, which was 45.97 times and 63.78 times higher than that of TiO2 and g-C3N4, respectively. In the photodegradation process, the TiO2/g-C3N4 (1 : 10) photocatalyst shows a removal rate of MB of 100 mg L−1, which was as high as 96.262%, significantly higher than that of pure TiO2 and g-C3N4. Brunner–Emmett–Teller (BET) measurements and Fourier transform infrared spectroscopy (FTIR) showed that the adsorption of MB onto TiO2/g-C3N4(1 : 10) was chemical adsorption, and ˙OH, which acts as an active substance, was found to play a major role in the photocatalytic degradation process. Overall, the developed hybrid phase TiO2/g-C3N4 heterojunction composite may be beneficial for the treatment of water pollution.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Biochar
·
2023
·Vol. 5
·期 1
·1-20
·
IF 12.7
Yang Bowen,Dai Jiawei,Zhao Yuan,Wang Zhanchao,Wu Jingwei,Ji Caiya,Zhang Yuhu,Pu Xiao
Biochar-coupled Fe 3 O 4 @SiO 2 /TiO 2 /g-C 3 N 4 composites were successfully constructed through simple sol–gel and calcination methods. The composites efficiently removed high-concentration toxic tetracycline (TC) by means of ·OH and · \({\rm O}_2^{-}\) , whose removal rate exhibited 91.88% during 3 h, and the degradation rate constant reached up to 0.0068 min −1 . The excellent performance can be attributed to the high specific surface area, enhanced visible light response, the introduction of magnetic nanoparticles and biochars expediting charge transfer, Z-scheme heterojunction enhancing the spatial separation of photo-generate carriers and, importantly extraordinary adsorption capacity of 147.96 mg g −1 . Moreover, the composites showed the most excellent efficiency under the calcination temperature of 450 ℃, and exhibited good stability with tolerance to a wide range of pH and anions. Interestingly, a synergistic photocatalytic effect was discovered in the TC/Cr(VI) combined pollution systems, resulting in significantly improved removal of Cr(VI). Besides, the photocatalytic mechanism and degradation path of tetracycline were also elucidated. All these findings suggested the as-synthesized catalyst was an excellent photocatalyst for removal of TC/Cr(VI)-contaminated water. Graphical Abstract
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
CHINESE CHEMICAL LETTERS
·
2020
·
IF 4.632
Sijia Sun,Hao Ding,Lefu Mei,Ying Chen,Qiang Hao,Wanting Chen,Zhuoqun Xu,Daimei Chen
Using low-cost precipitated silica (SiO 2 ) as the carrier, a ternary SiO 2 -TiO 2 /g-C 3 N 4 composite photocatalyst was prepared via the sol-gel method associated with a wet-grinding process. The as-prepared composite exhibits photocatalytic hydrogen production and pollutant degradation performance under solar-like irradiation. The effect of SiO 2 carrier on the properties of the heterostructure between TiO 2 and g-C 3 N 4 (CN) was systematically studied. It is found that SiO 2 has important effects on promoting the interaction between TiO 2 and CN. The particle size of TiO 2 and CN was obviously reduced during the calcination process due to the effects of SiO 2 . Especially, the TiO 2 particles exhibit monodispersed state with particle size below 10 nm (quantum dots), resulting in the improvement of the contact area and the interaction between TiO 2 and CN, and leading to the formation of efficient TiO 2 /CN Z-scheme heterostructure in SiO 2 -TiO 2 /CN. Besides, the introduction of SiO 2 can increase the specific surface area and light absorption of SiO 2 -TiO 2 /CN, further promoting the photocatalytic reaction. As expected, the optimum SiO 2 -TiO 2 /CN composite exhibits 12.3, 3.1 and 2.9 times higher photocatalytic hydrogen production rate than that of SiO 2 -TiO 2 , CN and TiO 2 /CN under solar-like irradiation, while the photocatalytic active component in SiO 2 -TiO 2 /CN is only about 60 wt%. Moreover, the rhodamine B degradation rate of SiO 2 -TiO 2 /CN is also higher than that of SiO 2 -TiO 2 , CN and TiO 2 /CN.
研究领域:
材料科学
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环境科学
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能源科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）