NANOTECHNOLOGY
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2023
·Vol. 34
·期 46
·465404
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IF 3.5
Penghui Bai,Kai Lei,Juan Xie,Hu Wang,Xiaolan Kang,Xia Wang
This paper investigates the impact of Pd/Ni modification on the photocatalytic hydrogen production performance of SrTiO3 (STO). STO catalysts were synthesized using a hydrothermal method, and Pd/Ni modification was applied on the surface of STO through chemical deposition. Experimental results demonstrate that the hydrogen evolution rate of Pd/Ni-modified STO (Pd/Ni-STO) reaches 2232.14 μmol g−1 h−1. X-ray absorption fine structure spectroscopy analysis reveals substitutional doping of Ni with Ti and coordination of Pd with surface O. X-ray photoelectron spectroscopy analysis indicates the introduction of oxygen vacancies due to Pd/Ni doping. Density functional theory calculations suggest that Ni doping activates neighboring Ti atoms, leading to the formation of bimetallic catalytic sites composed of oxygen vacancies and Ti atoms, greatly enhancing the photocatalytic hydrogen evolution performance. This study not only provides an effective catalyst for photocatalytic applications but also offers insights into the underlying mechanism, which may stimulate the development of metal-doped catalytic materials and have implications for a range of other applications.
研究领域:
材料科学
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能源科学
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催化化学
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DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2022
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IF 9.224
Yang Li,Zhaojian Zeng,Yuanming Zhang,Yong Chen,Wenjing Wang,Xiaoming Xu,Mengyang Du,Zhaosheng Li,Zhigang Zou
Photothermal catalytic reduction of CO2 is a powerful way to promote carbon neutralization goals. However, there are few reports on the deactivation of the photothermal CO2 reduction reaction. Here, we observed an interesting deactivation phenomenon of photothermal CO2 conversion over TiO2–xHx (black TiO2). Despite the presence of a reducing atmosphere of H2, the oxygen vacancy concentration of TiO2–xHx is reduced, resulting in the deactivation of photothermal CO2 reduction. After Ni is modified onto TiO2–xHx, Ni can activate H2 to form Hs, and the oxygen vacancy concentration of Ni/TiO2–xHx may be maintained, thus solving the deactivation problem in photothermal CO2 hydrogenation.
研究领域:
化学工程
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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
Journal of Materials Chemistry A
·
2021
·Vol. 9
·期 42
·24056-24063
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IF 12.732
Yanfang Chen,Xuemei Yan,Jixiang Xu,Lei Wang
H2O2 has a wide range of uses as an oxidant and is also utilized as a high density and environmentally friendly fuel. In this study, crystalline g-C3N4 was modified with K+, Ni and N-doped carbon by thermal-polymerization of Ni2+-anchored and polyvinyl pyrrolidone-encapsulated melamine-cyanuric acid supramolecules, followed by re-calcination in a KCl–LiCl mixture. The obtained strip-like g-C3N4 nanocrystals exhibited high charge separation efficiency and good light absorption capability. Density-functional theory calculations confirmed that the orbital hybridization of Ni–N atoms enabled the formation of charge-transfer channels, which can capture electrons, achieve enhanced oxygen adsorption and reduction via a two-electron pathway. Under the synergistic effects of K+, Ni and N-doped carbon dopants and crystallinity, the obtained sample exhibited high photocatalytic H2O2 yields of 79.6 μM in O2-saturated pure water, which was 10-fold higher than the yield using pristine g-C3N4. This work provides a novel design for production of highly efficient photocatalysts for H2O2 production.
研究领域:
材料科学
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环境科学
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化学
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DOI
高影响因子
SENSORS
·
2018
·Vol. 18
·期 10
·3493
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IF 2.475
Yingang Gui,Xiaoxing Zhang,Peigeng Lv,Shan Wang,Chao Tang,Qu Zhou
SF6decomposition components detection is a key technology to evaluate and diagnose the insulation status of SF6-insulated equipment online, especially when insulation defects-induced discharge occurs in equipment. In order to detect the type and concentration of SF6decomposition components, a Ni-modified carbon nanotube (Ni-CNT) gas sensor has been prepared to analyze its gas sensitivity and selectivity to SF6decomposition components based on an experimental and density functional theory (DFT) theoretical study. Experimental results show that a Ni-CNT gas sensor presents an outstanding gas sensing property according to the significant change of conductivity during the gas molecule adsorption. The conductivity increases in the following order: H2S > SOF2> SO2> SO2F2. The limit of detection of the Ni-CNT gas sensor reaches 1 ppm. In addition, the excellent recovery property of the Ni-CNT gas sensor makes it easy to be widely used. A DFT theoretical study was applied to analyze the influence mechanism of Ni modification on SF6decomposition components detection. In summary, the Ni-CNT gas sensor prepared in this study can be an effective way to evaluate and diagnose the insulation status of SF6-insulated equipment online.Keywords:SF6decomposition components;carbon nanotube sensor;Ni modification;adsorption;DFT calculations
研究领域:
材料科学
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电气工程
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理论化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Lian Xue,Ying Shi,Cunping Huang,Qiang Wu,Bingbing Chen,Weifeng Yao
Effective and affordable photocatalysts play an important role in the cost reduction of solar hydrogen production through photocatalytic water splitting. In this research, a Zn 2+ and Ni 2+ modified carbon hydrogen evolution cocatalyst (ZnNi-C) were synthesized and immobilized onto the surface of CdS (CdS@ZnNi-C) for photocatalytic hydrogen evolution (PHE). The preparation used an ethylenediaminetetraacetic acid disodium (EDTA)-assisted method. The hydrogen evolution rate and apparent quantum efficiency (AQE) at 420 nm for an optimized CdS@ZnNi-C photocatalyst are15.7 mmol/h/g and 31.4 %, respectively. The rate is 2.4 times and 3.7 times greater than those of Zn 2+ and Ni 2+ modified carbon cocatalysts (Zn-C) and (Ni-C) on CdS (CdS@Zn-C) and (CdS@Ni-C), respectively. Density functional theory calculations indicate that the elevated catalytic performance of CdS@ZnNi-C is due to the co-anchored Zn 2+ and Ni 2+ in carbon layers that lead to a favorable Gibbs free energy (ΔG H *) for hydrogen evolution. This approach is valuable for the design of stable and efficient photocatalysts for renewable hydrogen production.
研究领域:
材料科学
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可再生能源
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产品关联
DOI
PubMed
高影响因子
Polymers
·
2023
·Vol. 15
·期 13
·2791
·
IF 5
Mingqiang Shao,Yiran Shi,Jiangtao Liu,Baoxia Xue,Mei Niu
Improving the residual char of polypropylene (PP) is difficult due to the preferential complete combustion. Here, we designed a combination catalyst that not only provides physical barrier effects, but also dramatically promotes catalytic charring activity. We successfully synthesized WS2monolayer sheets decorated with isolated Ni atoms that bond covalently to sulfur vacancies on the basal planes via thiourea. Subsequently, PP blends composed of 8 wt.% Ni-decorated WS2, NiO, and activated carbon (AC) were obtained (ENi-SWS2-AC-PP). Combining the physical barrier effects of WS2monolayer sheets with the excellent catalytic carbonization ability of theENi-SWS2-AC combination catalyst, the PP blends showed a remarkable improvement in flame retardancy, with the yield of residual char reaching as high as 41.6 wt.%. According to scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations, it was revealed that the microstructure of residual char contained a large number of carbon nanotubes. The production of a large amount of residual char not only reduced the release of pyrolytic products, but also formed a thermal shield preventing oxygen and heat transport. Compared to pure PP, the peak heat release rate (pHRR) and total heat release rate (THR) ofENi-SWS2-AC-PP were reduced by 46.32% and 26.03%, respectively. Furthermore, benefiting from the highly dispersed WS2, the tensile strength and Young’s modulus ofENi-SWS2-AC-PP showed similar values to pure PP, without sacrificing the toughness.Keywords:polypropylene;Ni-modified monolayer WS2;sulfur vacancy;activated carbon;NiO;carbon nanotubes;flame retardancy;mechanical properties
研究领域:
材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）