Journal of Environmental Sciences
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2023
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IF 6.9
Jiaojiao Guan,Daorong Li,Jiahui Feng,Peng Xu,Zhaonian Li,Siqi Ge,Hongxia Chen,Kunfeng Zhang
The removal of ammonia (NH 3 ) emitted from agricultural and industrial activities is of great significance to protect human health and ecological environment. Photocatalytic NH 3 oxidation to N 2 under mild conditions is a promising strategy. However, developing visible light photocatalysts for NH 3 oxidation is still in its infancy. Here, we fabricate N-TiO 2 and Ag/AgCl/N-TiO 2 photocatalysts by sol-gel and photodeposition methods, respectively. The introduction of N not only endows TiO 2 with visible light response (absorption edge at 460 nm) but also results in the formation of heterophase junction (anatase and rutile). Thus, N-TiO 2 shows 2.0 and 1.8 times higher than those over anatase TiO 2 and commercial TiO 2 for NH 3 oxidation under full spectrum irradiation. Meanwhile, surface modification of Ag can simultaneously enhance visible light absorption (generating localized surface plasmon resonance effect) and charge separation efficiency. Therefore, the photocatalytic activity of Ag/AgCl/N-TiO 2 is further improved. Furthermore, the presence of N and Ag also enhances the selectivity of N 2 product owing to the change of reaction pathway. This work simultaneously regulates photocatalytic conversion efficiency and product selectivity, providing some guidance for developing highly efficient photocatalysts for NH 3 elimination.
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
Molecular Catalysis
·
2025
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IF 4.9
Bo Jiang,Shu-Lin Liu,Zhe-Yan Jin,Zhao Wang,Bin-Can Cheng,Ze-Long Guan,Ying Hong,Zhao Wei,Zhi Qiao,Jian Tao,Bao-Lian Su
Selective hydrogenation driven by heat is a critical industrial process for purifying alkene feedstocks with serious problems of energy and H 2 consumption. Photochemistry-assisted strategy offers a sustainable alternative owing to its superiority of H 2 -free reaction under ambient temperature, unfortunately, with a challenging demand on efficient catalysts. Herein, a wide-spectrum-responsive Pd/N-TiO 2 photo-thermal catalyst was developed by a solvothermal method for photochemistry-assisted selective hydrogenation of butadiene in propene. It shows an excellent catalytic performance, with 100 % alkenes selectivity and 100 % butadiene conversion under irradiation of full-light (i.e., 320 nm∼780 nm). Notably, over 53 % butadiene conversion with 100 % alkenes selectivity was successfully retained on Pd/N-TiO 2 after shortening the wavelength range to visible light, much superior to that on Pd-TiO 2 (i.e., <1 % butadiene conversion). Further exploration reveals that the nitrogen doping extends the light-responsive wavelength of titanium oxide from ∼380 nm to above 500 nm owing to the formation of Ti 3+ and oxygen vacancies, which later create a defect energy level (i.e., ∼-0.53 to -0.12 eV) between the valence-conduction band of TiO 2 . The wide spectral response of N-TiO 2 enhances the water photolysis to produce intermediate hydrogen ([H]) that acts as the hydrogen source for the tandem butadiene hydrogenation over the Pd surface. The work indicates that developing a dual-functional catalyst with an expanded light-responsive wavelength is an efficient way to enhance the photochemistry-assisted selective hydrogenation.
研究领域:
化学工程
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材料科学
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催化化学
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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2024
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IF 10.8
Huihui Wang,Qian Zhao,Daiqiang Li,Zhilin Zhang,Yuan Liu,Xueli Guo,Xiaotong Li,Zhi Liu,Lian Wang,Jinzhu Ma,Hong He
Photothermal catalysis is extremely promising for the removal of various indoor pollutants owing to its photothermal synergistic effect, while the low light utilization efficiency and unclear catalytic synergistic mechanism hinder its practical applications. Here, nitrogen atoms are introduced, and Pt nanoparticles are loaded on TiO2 to construct Pt/N-TiO2-H2, which exhibits 3.5-fold higher toluene conversion rate than the pure TiO2. Compared to both photocatalytic and thermocatalytic processes, Pt/N-TiO2-H2 exhibited remarkable performance and stability in the photothermocatalytic oxidation of toluene, achieving 98.4% conversion and 98.3% CO2 yield under a light intensity of 260 mW cm–2. Furthermore, Pt/N-TiO2-H2 demonstrated potential practical applicability in the photothermocatalytic elimination of various indoor volatile organic compounds. The synergistic effect occurs as thermocatalysis accelerates the accumulation of carboxylate species and the degradation of aldehyde species, while photocatalysis promotes the generation of aldehyde species and the consumption of carboxylate species. This ultimately enhances the photothermocatalytic process. The photothermal synergistic effect involves the specific conversion of intermediates through the interplay of light and heat, providing novel insights for the design of photothermocatalytic materials and the understanding of photothermal mechanisms.
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
CATALYSIS TODAY
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2022
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IF 6.562
Yunfei Ma,Wenhui Yue,Zehong Xu,Ziwei Ye,Jinlong Zhang
Composite nanoparticles consisting upconversion nanoparticles (β-NaYF 4 :Yb/Er) and nitrogen doped TiO 2 nanoparticles were constructed via a chemical assembly method. Efficient energy transfer was enabled since the upconverted energy matched up with the band gap of N-TiO 2 . This enables the resulting composite nanoparticles to possess excellent Rhodamine B (RhB) degradation activity under near infrared (NIR) light irradiation.
研究领域:
材料科学
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环境科学
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纳米技术
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DOI
高影响因子
Coatings
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2022
·Vol. 12
·期 5
·585
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IF 3.236
Wen Sun,Xuankun Li,Jingtao Zou,Han Guo
TiO2is widely used for the photocatalytic degradation of organic pollutants in wastewater, but the practical applications of the photocatalyst are limited due to its poor visible light absorption and low recovery rate. In this study, high production of nitrogen-doped TiO2was achieved by a hydrolysis precipitation method; the obtained N-TiO2had a small crystallite size and good dispersibility. The effect of calcining temperature on the photocatalytic performance of N-TiO2was evaluated through the degradation of methylene blue (MB) in a blue light LED irradiation cylinder, it was found the N-TiO2calcined at 400 °C showed the best photocatalytic activity. Then the N-TiO2was immobilized on SiC ceramic foam by dip-coating with PVA as the binder. The prepared N-TiO2/SiC foam showed excellent photocatalytic activity under blue light LED irradiation; as high as 96.3% of MB was degraded at optimum conditions. After five cycles of MB photodegradation, the photocatalytic activity of N-TiO2/SiC foam only changed slightly, which makes it a promising photocatalytic material for wastewater treatment.Keywords:nitrogen-doped TiO2;SiC foam;LED irradiation;photodegradation;methylene blue
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Yijiang Ge,Qinrui Sun,Hongtao Bai,Jingde Li,Xiaohang Du
Degradation of organic pollutants by in-situ electrochemically synthetic hydrogen peroxide (H 2 O 2 ) in electro-Fenton (EF) system is important for the treatment of wastewater. In this work, a Fe, Mo co-doped N@TiO 2 electrocatalyst was constructed for H 2 O 2 generation and applied to the degradation of organic dyes. The FeMoN@TiO 2 catalyst in 0.1 M KOH exhibits excellent 2e - Oxygen reduction reaction (ORR) activity and stability, with a yield of up to 1409 mmol gcat -1 h −1 and Faraday efficiency (FE) of 83.4 % at −0.7 V (relative to SCE) for more than 10 h. The in situ generated H 2 O 2 delivers benign organic dyes degradation ability with high methylene blue (MB) removal rate of 98.2 % after 2 h in 0.1 M KOH without adding Fe 2+ . After adding Fe 2+ , the EF process occurs to degrade dyes more efficiently, with Congo red and phenol removal rates of more than 99.0 % and Ciprofloxacin (CIP) removal rate of more than 96.0 % in 0.1 M Na 2 SO 4 solution. It is found that Mo doping increases the active sites of the catalyst, while the dopant of Fe can enhance can improve the electron transfer rate between the catalyst and reactants. Additionally, the synergistic Fe and Mo modulate the electronic structure of Ti, increasing the concentrations of Ti 3+ and chemiadsorbed O. This enhances the electronic conductivity and the reactivity of the catalyst, leading to improved ability for H 2 O 2 generation and organic pollutants degradation. Radical quenching experiments show that the in-situ generated H 2 O 2 reacts with added Fe 2+ to produce a large amount of ·OH, which is the main active substance for organic pollutants degradation. This study provides new insights for non-precious metal oxides to replace precious metals towards in-situ production of H 2 O 2 and degradation of pollutants.
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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产品关联
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
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2019
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IF 1.795
Jiajia Sun,Sheng Feng,Shanshan Feng
A novel ternary heterojunction MWCNT/N-TiO 2 /UiO-66-NH 2 was synthesized by in-situ solvothermal-hydrothermal approach, showing superior photocatalytic degradation of KET under visible-light irradiation. The optimal MWCNT/N-TiO 2 /UiO-66-NH 2 (3:7) composite exhibits the highest degradation efficiency of KET (96%) in 120 min in comparison with pristine TiO 2 , N-TiO 2 , MWCNT , UiO-66-NH 2 and MWCNT/N-TiO 2 . The improved photocatalytic activity of MWCNT/N-TiO 2 /UiO-66-NH 2 can be ascribed to its improved visible-light absorption range, the large specific surface area based on UiO-66-NH 2 as well as the formation of an effective heterojunction. The formed ternary composite facilitates the separation and transfer of photoexcited charge carrier, which is confirmed from the results of PL. The photocatalytic mechanism is further proposed based on the trapping experiment, and the transfer process of photoinduced electron-hole pairs is discussed. This work provides an effective strategy for designing a new ternary photocatalytic system toward degradation of organic pollutants.
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
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
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2017
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IF 2.084
Mingming Zou,Fengqiang Xiong,Ayyakannu Sundaram Ganeshraja,Xiaohua Feng,Chuanxi Wang,Tiju Thomas,Minghui Yang
Iron (III) and nitrogen co-doped mesoporous TiO 2 microspheres (Fe-N-TiO 2 ) are prepared using a self-assembly based solvothermal process followed by an ammonothermal method. Among all samples, 1 mol.% of Fe dopants and 500 °C nitridation (for 2 h) gives the highest visible light photoactivity. Results imply that the Fe 3+ /Fe 2+ dopant trap energy level introduced within the band gap in mildly Fe (∼1 at%) doped TiO 2 and the mesoporous nature of the material, both aid in the observed catalytic performance. Subjecting Fe-TiO 2 samples to ammonothermal process induces oxygen vancancies, and substitutional and interstitial N. This reduces optical band gap, and introduces local states. The lower band gap and local states together aid in the absorption of visible light and separation of charge carriers. Co-dopants are distributed uniformly in the best photocatalysts . The active species generated in the photocatalytic system is shown to be singlet molecular oxygen ( 1 O 2 ) using selective radical quenchers.
研究领域:
材料科学
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化学工程
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环境科学
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产品关联
DOI
高影响因子
Surfaces and Interfaces
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2024
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IF 5.7
Lai Liu,Ye Tian,Jiangang Yu,Huizhen Yao
Copper zinc sulphide (CZS) due to high conductivity, fast photoresponse and good stability has attracted rising attention in optoelectronic field. Constructing heterojunctions with rational energy bands alignment can accelerate carrier separation to improve the performance of CZS-based photoelectric device. Herein, p-CZS/n-TiO 2 core-shell nanorods heterojunction film was successfully fabricated for the first time. CZS nanoparticles (NPs) were directly loaded on the surface of TiO 2 nanorods (NRs) through a simple chemical bath deposition. Photoelectrochemical (PEC) photodetector based on CZS/TiO 2 composite film was designed and interfacial charge kinetics has also been investigated. The CZS/TiO 2 PEC device exhibits fast response speed of 95/56 ms, high responsivity of 7.1 mA W -1 and detectivity of 5.6 × 10 12 Jones at a bias voltage of 1 V. The light on/off ratio of self-powered CZS/TiO 2 PEC device achieves 5.6 × 10 3 , nearly 30.4 times higher than bare CZS PEC device. Furthermore, the photodetection performance of the CZS/TiO 2 PEC device can be effectively regulated by light power density and environment conditions, promoting its adaptability in multifarious practical applications. The findings suggest that CZS/TiO 2 heterostructure film devices have great potential for high-performance and energy-efficient PEC photodetectors.
研究领域:
材料科学
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光电子学
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产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2016
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IF 8.328
Xuefeng Liu,Zipeng Xing,Yan Zhang,Zhenzi Li,Xiaoyan Wu,Siyu Tan,Xiujuan Yu,Qi Zhu,Wei Zhou
As is well-known, it is a great challenge that the smooth TiO 2 nanospheres are coated by MoS 2 nanosheets to form the core-shell nanostructure owing to their poor interaction. Herein, we report 3D black N-TiO 2-x @MoS 2 core-shell nanostructures synthesized by a mild and effective strategy combined with a typical hydrothermal reaction and an in situ solid-state chemical reduction method followed by 350 °C calcination under an argon atmosphere. The prepared samples are characterized in detail by X-ray diffraction, Raman, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The results suggest that the 3D N-TiO 2-x @MoS 2 photocatalyst is successfully doped with N and Ti 3+ , and simultaneously coupling with MoS 2 to form the core-shell heterojunction nanostructure. The N and Ti 3+ co-doped and hybrid heterostructures can effectively utilize visible-light and solar energy to degrade methyl orange and produce hydrogen. The degradation rate of methyl orange and the hydrogen production rate are as high as 91.8% and 1.882 mmol h −1 g −1 . To the best of our knowledge, this work is the first instance of combining MoS 2 with N and Ti 3+ co-doped TiO 2 , and the proposed photocatalytic mechanism will provide a new perspective for high activity photocatalyst in future.
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
高影响因子
APPLIED SURFACE SCIENCE
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2022
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IF 7.392
Lixin Zhang,Lei Rao,Peifang Wang,Zhenyu Shi
TiO 2 nanoparticles are promising photocatalysts for the remediation of water pollution. However, the difficulty in recycling and low light absorption of powder TiO 2 hinder their application in photocatalysis. Although some studies have attempted to address these problems by immobilizing TiO 2 , the application of traditional immobilized TiO 2 in water environment is limited because of their unstable immobilization, poor mechanical strength, low light utilization, high electron-hole recombination,and unsatisfactory photocatalytic performance. In this study, flexible superhydrophobic Nitrogen-doped TiO 2 (N-TiO 2 ) silicone composite aerogels were achieved by copolymerization of γ-methacryloxypropyl trimethoxy silane (KH570)-grafted N-TiO 2 with methyltrimethoxysilane and dimethoxydimethylsilane. These flexible composite aerogels possess improved mechanical strength and stable immobilization of N-TiO 2 . Moreover, an air–liquid–solid triphase photocatalytic interface was formed by the superhydrophobic surface of composite aerogel, solution and the air layer existed between them. This triphase photocatalytic interface enabled oxygen at the reaction interface to be directly and rapidly supplied from the air layer, thus photogenerated electrons from the photocatalyst surface can be effectively removed and the recombination of electron holes can be reduced. Besides, the flexible photocatalyst was molded into water grass shape and placed in a water channel to verify its photodegradation efficiency and durability under hydrodynamic conditions. Experimental results confirmed that the proposed flexible photocatalyst with a triphase catalytic interface has application prospects for the degradation of pollutants in water environment.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Fengyu Gao,Jiyue Zhang,Jiaying Jiang,Xiaolong Tang,Yuansong Zhou,Honghong Yi
This paper explores an eco-friendly and efficient photocatalytic oxidation (PCO) technology aimed at converting NH 3 into N 2 , which holds considerable importance for environmental conservation and human well-being. Building upon previous investigations of N-TiO 2 catalysts, the research group successfully synthesized an N-TiO 2 catalyst featuring a carbon layer on its surface via mechanical mixing followed by calcination at 400 °C (denoted as C/N-TiO 2 (1), 1 represents the molar ratio of N and Ti). The analysis concentrated on the influence of C content on the PCO efficiency of NH 3 , revealing a peak performance correlated with increasing C levels. Notably, the C/N-TiO 2 (1) catalyst with 3.0 wt% C exhibited remarkable catalytic performance, achieving a conversion rate of 94 % and selectivity of 98 %. The enhancement of catalytic activity and selectivity is primarily attributed to the co-doping of C and N elements. Experimental results indicate that doping with N alone effectively suppresses the recombination of photogenerated carriers under visible light. Furthermore, the simultaneous doping of C and N significantly reduces the band gap energy of TiO 2 (3.18 to 2.90 eV), thereby broadening its photoresponse range. Concurrently, more Ov (Oxygen vacancy) are formed under visible light irradiation, which enhances the PCO performance. More importantly, more acidic sites are introduced to improve the catalyst’s adsorption capacity for NH 3 . Additionally, the impact of various reaction components on the PCO capability of the 3.0 wt% C/N-TiO 2 (1) catalyst is examined further. The findings indicate that oxygen anion radicals produced from O 2 play a critical role in facilitating NH 3 -PCO. However, the presence of CO 2 and extra H 2 O could hinder the approach of NH 3 molecules to the active sites and decrease the longevity of photogenerated ·OH, consequently reducing catalytic effectiveness. This research introduces fresh insights and optimization approaches for enhancing the activity, selectivity, and stability of catalysts.
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
危险品化学品经营许可证（带存储）