Energy Technology
·
2019
·Vol. 7
·期 7
·1900017
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IF 3.163
Zhongyi Du,Pengju Sun,Kuanhuai Wu,Xiarong Zheng,Xingfeng Zhang,Jiale Huang,Daohua Sun,Yanmei Zheng,Qingbiao Li
Graphite carbon nitride (g-C 3 N 4 ) and SiC have drawn increasing attention for application in visible light photocatalytic hydrogen evolution by water splitting due to their unique band structure and high physicochemical stability. Herein, a g-C 3 N 4 -SiC heterojunction with loaded noble metal is constructed. The g-C 3 N 4 -SiC-Pt composite photocatalysts are successfully prepared by the combination method of bio-reduction, sol deposition, and calcination. The layers of g-C 3 N 4 are thinned, and both SiC and Pt nanoparticles are simultaneously tightly bound to g-C 3 N 4 by calcination during the preparation of g-C 3 N 4 -SiC-Pt. The heterojunction formed at the interface of SiC and g-C 3 N 4 enhances the separation efficiency of the photogenerated electron–hole pairs. These composite photocatalysts achieve a high hydrogen evolution rate of 595.3 μmol h −1 g −1 with 1 wt% of deposited Pt, which is 3.7- and 2.07-fold higher than those of g-C 3 N 4 -bulk and g-C 3 N 4 -SiC under visible light irradiation with a quantum efficiency of 2.76% at 420 nm, respectively.
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
RSC Advances
·
2020
·Vol. 10
·期 29
·17154-17162
·
IF 3.119
Ang Li,Yuxiang Liu,Xuejun Xu,Yuanyuan Zhang,Zhichun Si,Xiaodong Wu,Rui Ran,Duan Weng
Constructing Z-scheme heterojunctions is considered as an effective strategy to obtain catalysts of high efficiency in electron–hole separation in photocatalysis. Unfortunately, suitable heterojunctions are difficult to fabricate because the direct interaction between two semiconductors may lead to unpredictable negative effects such as electron scattering or electron trapping due to the existence of defects which causes the formation of new substances. Furthermore, the van der Waals contact between two semiconductors also results in bad electron diffusion. In this work, a MOF-derived carbon material as a Z-scheme photocatalyst was synthesized via one-step thermal treatment of MoS2 dots @Fe-MOF (MIL-101). Under visible light irradiation, the well-constructed Z-scheme (MoS2, γ-Fe2O3)/graphene photocatalyst shows 2-fold photocatalytic oxygen evolution activity (4400 μmol g−1 h−1) compared to that of γ-Fe2O3/graphene (2053 μmol g−1 h−1). Based on ultraviolet photoelectron spectrometry (UPS), Mott–Schottky plot, photocurrent and photoluminescence spectroscopy (PL) results, the photo-induced electrons from the conduction band of γ-Fe2O3 could transport quickly to the valence band of MoS2 via highly conductive graphene as an electron transport channel, which could significantly enhance the electron–hole separation efficiency as well as photocatalytic performance.
研究领域:
材料科学
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光催化
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2019
·
IF 8.355
Shumin Li,Jun Tan,Zhejun Jiang,Jin Wang,Zhengquan Li
Dye-sensitized systems show promising in photocatalysis because they can separate the tasks of light absorption, charge generation and surface catalysis to two coupled components. In this system, it is crucial to develop suitable catalysts capable of receiving dye-injected charges and having high activity to a given reaction. Aiming to photocatalytic H 2 and O 2 production, we present a metal-organic framework derived route to prepare bimetallic Fe-Ni-P nanotubes using Fe-Ni-MIL-88 nanorods as templates. When integrated with different dyes, these Fe-Ni-P nanotubes can serve as efficient catalysts for photocatalytic H 2 and O 2 production, respectively. Additionally, catalytic activities of such dye-sensitized systems can be conveniently regulated by tailoring the metal compositions in Fe-Ni-P nanotubes. The photocatalytic H 2 production of Fe 1 -Ni 2 -P can reach 5420 μmol g cat −1 h −1 under eosin-Y sensitization, which is 24 times and 6.7 times higher than Fe 2 P and Ni 2 P, respectively. The photocatalytic O 2 production of Fe 1 -Ni 2 -P can reach 900.3 μmol g cat −1 h −1 under [Ru(bpy) 3 ]Cl 2 sensitization, about 4.6 times and 2.9 times higher than Fe 2 P and Ni 2 P. The roles of different components in the system have been explored and corresponding working mechanism is proposed. This work demonstrates a new type of dye-sensitized systems consisting of bimetallic phosphides and provides a facile route to regulate their photocatalytic performance.
研究领域:
材料科学
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光催化
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Xinwei Zhang,Xiaotian Zhang,Rong Wang,Yijia Zhong,Kunting Li,Lei Xu,Huimin Feng
S-scheme heterojunction catalysts have attracted much attention due to their ability to effectively separate photo-generated electrons and holes while optimizing the redox ability of carriers. We have prepared an efficient visible-light catalytic PDPB/Ag–TiO 2 S-scheme heterojunction by in-situ synthesis methods . The catalysts were characterized for their structure, composition , morphology, and photoelectrochemical properties. The hydrogen production rate of PDPB/Ag–TiO 2 -2 was 1473.6 μmol/g/h. The results of SPV analysis showed that the spontaneous interfacial charge transfer from PDPB to Ag–TiO 2 in the contact interface region resulted in the presence of an internal electric field . This enhanced internal electric field effectively drove directional charge migration through the S-scheme mechanism, improving charge separation and utilization. The PDPB/Ag–TiO 2 -2 composites also maintained stable photocatalytic activity after running for four cycles. Overall, this study brings fresh preparation ideas for the conjugated polymer-TiO 2 composites with high photocatalytic efficiency.
研究领域:
材料科学
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能源化学
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光催化
✓ 已验证
产品关联
DOI
高影响因子
Science China-Materials
·
2018
·Vol. 61
·期 7
·1001-1006
·
IF 4.318
Zhang Guo-Qiang,Ou Wei,Xu Yang-Sen
氢能源是未来最理想的清洁能源, 可以利用太阳能和光催化材料分解水获得. 开发廉价、 资源丰富、 环境友好的光催化材料, 成为近年来能源和环境领域的研究热点. 基于此, 我们报道了一种新型有机光催化材料-不含金属的荧光素超分子纳米片, 其在可见光下显示出高效的光催化分解水产氢活性, 产氢速率接近341 μmol g −1 h −1 , 在420±10 nm的波段下表观量子效率达到1.2%. 这是荧光素超分子晶体首次被报道并应用于可见光下分解水产氢, 这一发现丰富了有机和超分子光催化剂的种类.
研究领域:
光催化
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能源材料
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超分子化学
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清洁能源
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光化学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
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IF 20.2
Guoqiang Zhang,Xiaojun Zhang,Yangsen Xu,Peixin Zhang,Yongliang Li,Chuanxin He,Hongwei Mi
The role of defects in photocatalysis is rarely investigated more intuitively from the perspective of defect ionization energy (DIE), although it is the most important parameter for evaluating the depth of defect traps. Here, the crystalline poly(heptazine imide) (PHI) is adopted as an illustrative example to optimize the DIE and charge separation by regulating the carbon doping contents, ultimately activating the near-infrared photocatalytic activity . Shallow defect traps induced by doping (DIE < 25 meV) facilitate charge separation by releasing shallowly trapped carriers. In contrast, deep defect traps (DIE > 25 meV) act as non-radiative recombination centers , causing carrier quenching. More importantly, the non-radiative recombination rate in PHI is 1–2 orders of magnitude faster than the radiative recombination rate , so suppressing non-radiative recombination is more important for improving charge separation efficiency. Our work elucidates the role of defects in photocatalysis more intuitively from the perspective of DIE, and establishes a discernible relationship between DIE and photocatalytic activity .
研究领域:
材料科学
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光催化
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产品关联
DOI
高影响因子
CATALYSIS LETTERS
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2020
·Vol. 151
·期 7
·1961-1975
·
IF 2.482
Wei Congcong,Zhang Wei,Wang Xinpeng,Li Aihong,Guo Jianping,Liu Bo
Abstract Here, g-C 3 N 4 /TiO 2 photocatalysts with mesoporous structure and intimate interfacial connection were synthesized via the facile pyrolysis of g-C 3 N 4 /MIL-125 composites. The photocatalytic H 2 evolution reaction was performed to examine the photocatalytic activity of obtained photocatalysts. Under the UV–vis light irradiation, the average H 2 evolution rate of g-C 3 N 4 /TiO 2 sample with optimal g-C 3 N 4 loading content (4.12wt%) was most increased by up to 0.606 mmol·g −1 ·h −1 , a value which transcended that of as-prepared g-C 3 N 4 (0.138 mmol·g −1 ·h −1 ) and mesoporous TiO 2 (0.244 mmol·g −1 ·h −1 ) by a factor of 4.41 and 2.48, respectively. The improvement in photocatalytic activity of g-C 3 N 4 /TiO 2 composites was explained by the synergistic effect between large specific surface area, decreased energy band gap and intimate interface contact. This study demonstrated a new approach for the preparation of binary mesoporous heterojunction photocatalysts. Graphical Abstract
研究领域:
材料科学
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光催化
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DOI
高影响因子
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
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环境化学
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纳米催化
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光催化
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无机功能材料
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能源材料
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2022
·
IF 10.319
Yong Wang,Chengxin Zeng,Liting Wu,Yalin Dong,Yu Zhang,Dingyi Yang,Wen Hu,Jian Hao,Hongzhe Pan,Rusen Yang
Two-dimensional (2D) carbon nitride sheets (CNs) with nanoscale thickness have great potential in solar energy conversion owing to their intrinsic bandgap. However, their photocatalytic efficiency falls far below the practical requirements because the generated electron-hole pairs rapidly recombine. We construct a metal-free 2D p–n junction heterophotocatalyst from CNs and violet phosphorene (VP) using a simple electrostatic self-assembly method. The experimental results and density functional theory calculations show that the built-in electric field of the p–n junction promotes photogenerated carrier transport at the heterojunction interface, thereby promoting the separation of photogenerated electron-hole pairs. Under visible-light illumination, the visible-light photocatalytic hydrogen and CO production rates of the CNs/VP heterojunction were increased by 5.85 and 1.51 times, respectively, when compared to that of CNs . This study provides new insights into the design of metal-free heterogeneous photocatalysts with high catalytic activity.
研究领域:
材料科学
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光催化
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纳米材料
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能源化学
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半导体物理
✓ 已验证
DOI
高影响因子
WATER SCIENCE AND TECHNOLOGY
·
2018
·Vol. 77
·期 5
·1441-1448
·
IF 1.247
Li Yuejin,Shang Xili,Li Changhai,Huang Xiaoming,Zheng Jingjing
Novel visible-light-induced UiO-66/BiOI photocatalysts with a p–n junction structure have been prepared for the first time through a facile hydrothermal method. The prepared photocatalysts were characterized using the powder X-ray diffraction, high resolution transmission electron microscopy, scanning electron microscopy, UV–visible diffuse reflectance spectra, and N 2 adsorption–desorption (Brunauer–Emmett–Teller) techniques respectively. The photodegradation performances of UiO-66/BiOI photocatalysts were evaluated by photodegrading salicylic acid under visible-light irradiation. The UiO-66/BiOI composites displayed much higher photocatalytic efficiencies than pure BiOI under visible light. When the content of UiO-66 was 5.2 wt%, the composite (UiO-66/BiOI-2) has the best photocatalytic activity. Most of the salicylic acid molecules can be degraded in 100 min. The degradation rate of UiO-66/BiOI-2 samples is higher than single BiOI and UiO-66. The enhanced photocatalytic performance of UiO-66/BiOI may be ascribed to the formation of p–n heterojunctions between BiOI and UiO-66, which facilitates the transfer and separation of the photogenerated charge carriers. After recycling of the photocatalyst for five times for the photodegradation of salicylic acid, more than 85% of salicylic acid could still be degraded in the fifth cycle, implying that the as-prepared photocatalysts are highly stable.
研究领域:
环境化学
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材料科学
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光催化
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纳米材料
·
环境功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2017
·Vol. 29
·期 4
·2733-2742
·
IF 2.019
Hou Huilin,Wang Lin,Yang Weiyou,Gao Fengmei
Fe-doped TiO 2 nanofibers with a thoroughly mesoporous structure were prepared via a facile foaming-assisted electrospinning method. The foaming agents and FeAcAc were introduced in the raw materials to create the mesopores and incorporate the Fe dopants into the conventional solid TiO 2 nanofibers, respectively, which could be accomplished simultaneously over a one-step calcination process. The photocatalytic experimental results demonstrate that the mesoporous Fe-doped TiO 2 nanofibers exhibit significantly enhanced activity toward the RhB degradation and splitting water for hydrogen generation under visible-light illumination, as compared to those of Fe-doped solid and intrinsic thoroughly mesoporous counterparts. The photocatalytic mechanism is proposed that the one-dimensional mesoporous nanostructure can enhance the transportation of the reactant and products, and the Fe-doping induces the shift of the absorption edge into the visible-light range and restrains the recombination of photo-generated electrons and holes, which can synergistically improve their activity.
研究领域:
材料科学
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纳米科技
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光催化
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环境功能材料
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能源材料
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2018
·
IF 4.439
Zhengliang Zhao,Xuelin Wang,Zhu Shu,Jun Zhou,Tiantian Li,Wenbin Wang,Yigen Tan
Mesoporous g-C 3 N 4 consisting of hollow nanospheres (MCNHN) was prepared via a facile vapor-deposition method. It demonstrated an excellent visible-light photocatalytic H 2 evolution activity of 22.3 times greater than bulk g-C 3 N 4 . The special hollow nanosphere structure, increased specific surface area and modified crystalline enabled MCNHN to realize stronger light harvest and better photoinduced electron-hole separation, which leaded to highly improved photocatalytic performance. The proposed method and setup are easy to be established, and have the potential for preparing nanoscale g-C 3 N 4 with other tailored nanostructures.
研究领域:
材料科学
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光催化
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纳米材料
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能源化学
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半导体催化
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）