Journal of Environmental Sciences
·
2017
·
IF 2.865
Yanfeng Wang,Wei Chen,Xiao Chen,Huajun Feng,Dongsheng Shen,Bin Huang,Yufeng Jia,Yuyang Zhou,Yuxiang Liang
CdS/MoS 2 , an extremely efficient photocatalyst , has been extensively used in hydrogen photoproduction and pollutant degradation . CdS/MoS 2 can be synthesized by a facile one-step hydrothermal process. However, the effect of the sulfur source on the synthesis of CdS/MoS 2 via one-step hydrothermal methods has seldom been investigated. We report herein a series of one-step hydrothermal preparations of CdS/MoS 2 using three different sulfur sources: thioacetamide, l -cysteine, and thiourea . The results revealed that the sulfur source strongly affected the crystallization, morphology, elemental composition and ultraviolet (UV)–visible-light-absorption ability of the CdS/MoS 2 . Among the investigated sulfur sources, thioacetamide provided the highest visible-light absorption ability for CdS/MoS 2 , with the smallest average particle size and largest surface area, resulting in the highest efficiency in Methylene Blue (MB) degradation. The photocatalytic activity of CdS/MoS 2 synthesized from the three sulfur sources can be arranged in the following order: thioacetamide > l -cysteine > thiourea . The reaction rate constants ( k ) for thioacetamide, l -cysteine, and thiourea were estimated to be 0.0197, 0.0140, and 0.0084 min −1 , respectively. However, thioacetamide may be limited in practical application in terms of its price and toxicity, while l -cysteine is relatively economical, less toxic and exhibited good photocatalytic degradation performance toward MB.
研究领域:
材料科学
·
环境化学
·
纳米催化
·
光催化
·
无机功能材料
·
能源材料
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2018
·
IF 4.732
Chengwei Xu,Wenxia Xie,Xiaodong Si,Jun Zhang,Jiangang Yang
A TiO 2 /MWCNTs/Al 2 O 3 /NF (TiO 2 nanoparticles/multi-walled carbon nanotubes /Al 2 O 3 -modified nickel foams) composite filter was prepared through grown of MWCNTs upon Al 2 O 3 -modified nickel foams using chemical vapor deposition (CVD) method and then coated TiO 2 nanoparticles onto MWCNTs using dip-coating method. The MWCNTs forms a network-like structure on the surface layer of composite filter. The BET surface area of TiO 2 /MWCNTs/Al 2 O 3 /NF composite filter is more than 375 times higher than that of the pristine nickel foam. The degradation performance of oil particles was evaluated. Under optimized reaction conditions, 90% of the oleic acid on the filter was decomposed after 25 h. In addition, the effect of reaction temperature and light intensity were studied. Increased reaction temperature and light intensity were found to significantly improve the degradation rate and restrain the formation of refractory product. Furthermore, a parallel reaction kinetic model was adopted for degradation of oleic acid on the composite filter. The composite filter can reduces the accumulation of oil particles on the filter and the energy consumption of the filter. This approach proposes a new way to treat the cooking fume emission at residential building roofs.
研究领域:
环境科学
·
材料科学
·
化学工程
·
大气污染控制
·
纳米技术
✓ 已验证
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 59
·34658-34670
·
IF 3.049
Xiangyu Wang,Yu Xie,Jun Ma,Ping Ning
The two-stage removal process of tetracycline (TC) in aqueous solutions using a novel photocatalyst based on nano-zero-valent iron (NZVI), g-C3N4 and expanded graphite by carbon layer (EGC) is reported for the first time. The composite (NZVI/g-C3N4@EGC) exhibits remarkable adsorption, reduction ability and visible light activity over the reaction course. Compared with pristine g-C3N4 (25.9%) and pure NZVI (45.9%), NZVI/g-C3N4@EGC achieves high degradation efficiency of TC (98.5%) due to the formation of a heterogeneous photo-Fenton system. This study shows that synergistic effects are achieved in the reaction system, including maintaining the reduction ability of NZVI and enhancing the photocatalytic activity of g-C3N4 by facilitating the separation of photogenerated electrons (e−) and holes (h+). TC removal involved a two-stage process of adsorption–reduction and photo-degradation. The quencher experiments determined that holes (h+) and superoxide radicals (˙O2−) are the major reactive species in the degradation of TC. The degradation pathways of TC were proposed based on the analysis of the intermediates. In addition, NZVI/g-C3N4@EGC revealed a high stability in a five-cycle test and good magnetic properties for facile separation from aqueous solutions. From an application viewpoint, NZVI/g-C3N4@EGC has favorable prospects in the direction of the photocatalytic degradation of antibiotic wastewater.
研究领域:
环境化学
·
材料科学
·
光催化
·
水污染治理
·
纳米复合材料
·
抗生素降解
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2019
·
IF 3.131
Xiaotong Sun,Luting Yan,Runxiang Xu,Mingyuan Xu,Yanyun Zhu
TiO 2 presents a broad application prospect in the field of degradation of environmental pollutants. However, the development of TiO 2 photocatalyst has been limited by two factors, namely, narrow spectral response range and low quantum efficiency . Surface coating can selectively change the physical and chemical properties of core particles, whereas the synergistic action between core and shell can optimize material performance. In this paper, surface modification of titanium dioxide (TiO 2 ) by dopamine polymerization was used to improve its photocatalytic performance. Among polydopamine (PDA)-modified TiO 2 , TiO 2 @PDA-0.4 mg/mL-2 h showed the best degradation rate of Rhodamine B (RhB): the degradation rate reached 99.28% and 77.40% after 1.5 h of ultraviolet–visible (UV–vis) and visible (Vis) light irradiation, respectively. Compared with the uncoated TiO 2 , the degradation rate has shown improvement, especially under Vis light irradiation, with the photocatalytic performance improving by 35.04%. Absorption, emission, and impedance spectra showed that surface modification of TiO 2 with suitable thickness of PDA effectively increased light absorption and promoted separation of photogenerated carriers . High-performance liquid chromatography–mass spectrometry revealed the differences in photocatalytic degradation mechanism of TiO 2 @PDA to RhB under UV–vis and Vis light irradiation. Compared with those under UV–vis light irradiation, the intermediate products under Vis light irradiation are relatively simple. TiO 2 @PDA generated more electrons, which interacted with H 2 O to produce large amounts of ·OH and holes under UV–vis light irradiation in comparison with that under Vis light irradiation. In addition to deacetylation , deamination , and decarboxylation by hydroxylation , excess ·OH in the photocatalytic process would attack benzene rings directly to produce N , N -diethylacetamide.
研究领域:
材料科学
·
环境化学
·
光催化
·
纳米材料
·
表面工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2017
·Vol. 44
·期 6
·5842-5847
·
IF 2.986
Lirong Yang,Chunmei Wang,Zhigang Liu,Xiaoyu Liu,Yang Song,Xiaoxin Feng,Baoqiang Zhang
Anatase TiO 2 coatings prepared by solvothermal process in a neutral ethanol solution of isopropyl titanate at 160 °C have been grown on slag wool fibers (SWF) which were modified by hexadecyltrimethylammonium bromide (CTAB) in advance. X-ray diffraction patterns confirmed the coatings are of a nanocrystalline anatase structure, and scanning electron microscopy observations and energy-dispersive X-ray spectrum revealed a continuous coverage of TiO 2 formed on the fiber surfaces. The photocatalytic activity of the samples was tested by the photocatalytic degradation of methylene blue (MB) solution. The results show that CTAB modified slag wool fibers (CMSWF) are not a suitable adsorbent for MB due to their weaker negative surface charges. Anatase TiO 2 coated CMSWF display higher photocatalyst activity than anatase TiO 2 coated SWF without CTAB modification, and Anatase TiO 2 coated CMSWF are relatively stable under UV-light irradiation.
研究领域:
材料科学
·
环境功能材料
·
表面改性
·
光催化
·
纳米涂层
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2021
·
IF 6.498
Xueqian Yan,Jin Qian,Xiangjun Pei,Lihong Zhou,Rui Ma,Mingkuan Zhang,Yufei Du,Linqin Bai
In this study, a magnetic NiFe 2 O 4 /MWCNTs/BiOI composite were fabricated and applied for enhanced and sustainable photocatalytic degradation of doxycycline (DOX) under UV light irradiation. The as-synthesized material was characterized by a series of techniques and its photocatalytic property was assessed via a couple of batch tests. With the pH at 3.0 and NiFe 2 O 4 /MWCNTs/BiOI loading of 1.5 g L −1 , the DOX degradation (at 45 mg L −1 ) efficiency could achieve 92.18% with the reaction rate constant k of 0.0072 min −1 . The high mineralization of DOX suggests the strong oxidation of both the parent pollutant and the intermediary products in the ternary catalyst system. DRS spectra indicated that compared with BiOI , the introduction of NiFe 2 O 4 and MWCNTs reduces the band gap energy of the NiFe 2 O 4 /MWCNTs/BiOI. The quenching test illustrates that h + , OH and O 2 − all functioned in the developed photocatalytic system, where O 2 − and h + play the dominant roles in DOX degradation. The more efficient electron-h + separation and more oxidizing species induced by UV light resulted in the significant improvement of DOX abatement in the developed coupling system compared with that on either BiOI or NiFe 2 O 4 /MWCNTs. The magnetic property of NiFe 2 O 4 /MWCNTs/BiOI enables its easy separation of the solid catalyst from the reaction solution and the sustainable application in the photocatalysis . Based on the intermediates of DOX decomposition identified by UPLC-MS, the possible degradation routes were proposed accordingly.
研究领域:
环境化学
·
材料科学
·
光催化
·
水污染治理
·
纳米复合材料
·
药物降解
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）