Journal of Materials Chemistry A
·
2019
·Vol. 7
·期 30
·18092-18099
·
IF 10.733
Zheng Zhang,Peng Mu,Jingxin Han,Jingxian He,Zhaoqi Zhu,Hanxue Sun,Weidong Liang,An Li
Solar vapor generation based on light-to-heat conversion via photothermal materials has been considered as one of the emerging technologies for utilizing solar energy. Here, we report the fabrication of a novel monolithic aerogel (PNGA) composed of hydrophilic treated MnO2 nanowires and reduced graphene oxide (rGO) followed by in situ coating of polypyrrole on the surface of the PNGA to construct a light-to-heat conversion layer for efficient solar steam generation. Analysis of the morphology and porosity of the PNGA shows that the aerogel is full of interconnected pores and open channels with a low apparent density (0.127 g cm−3) and large specific surface area (1142.7 m2 g−1), which endow it with excellent thermal insulation (a low thermal conductivity of 0.21882 W m−1 K−1 in the wet state), self-floating and rapid water transmission properties. Benefiting from the polypyrrole coating, the PNGA shows a superintense optical absorption of ca. 100%. Interestingly, a superhydrophilic wettability could be achieved after surface modification of the PNGA with phytic acid, which could dramatically enhance its water transportation ability. Furthermore, the PNGA maintains a certain mechanical strength (0.08 MPa under 30% strain), thus making it mechanically robust to withstand the harsh environment. Taking the advantages mentioned above, our PNGA possesses an outstanding energy conversion efficiency of 93.8% under 1 kW m–2 irradiation, which is 4.9 times that of pure water (19.1%). In addition to the excellent ionic isolation and dye liquid treatment ability, the PNGA shows excellent stability and its energy conversion efficiency remains nearly unchanged after ten consecutive tests. Based on its excellent mechanical stability and high recyclability and a simple and scalable manufacture process, our PNGA sample may have great potential as an efficient photothermal material for a wide range of large-scale applications such as solar steam generation, wastewater treatment, seawater desalination and so on.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2023
·Vol. 13
·期 3
·588
·
IF 3.9
Haiou Zhang,Yixin Zhang,Huikang Song,Yan Cui,Yingying Xue,Cai-e Wu,Chao Pan,Jingxin Xu,Jian Qiu,Leilei Xu,Mindong Chen
As a toxic pollutant, carbon monoxide (CO) usually causes harmful effects on human health. Therefore, the thermally catalytic oxidation of CO has received extensive attention in recent years. The CuO-based catalysts have been widely investigated due to their availability. In this study, a series of transition metal oxides (Fe2O3, Co3O4and NiO) promoted CuO-based catalysts supported on the α-MnO2nanowire catalysts were prepared by the deposition precipitation method for catalytic CO oxidation reactions. The effects of the loaded transition metal type, the loading amount, and the calcination temperature on the catalytic performances were systematically investigated. Further catalyst characterization showed that the CuO/α-MnO2catalyst modified with 3 wt% Co3O4and calcined at 400 °C performed the highest CO catalytic activity (T90= 75 °C) among the investigated catalysts. It was supposed that the loading of the Co3O4dopant not only increased the content of oxygen vacancies in the catalyst but also increased the specific surface area and pore volume of the CuO/α-MnO2nanowire catalyst, which would further enhance the catalytic activity. The CuO/α-MnO2catalyst modified with 3 wt% NiO and calcined at 400 °C exhibited the highest surface adsorbed oxygen content and the best normalized reaction rate, but the specific surface area limited its activity. Therefore, the appropriate loading of the Co3O4modifier could greatly enhance the activity of CuO/α-MnO2. This research could provide a reference method for constructing efficient low-temperature CO oxidation catalysts.Keywords:transition metal oxides;CuO-based catalysts;Co3O4modification;α-MnO2nanowire;catalytic oxidation of CO
研究领域:
催化
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Yingguang Zhang,Muyan Wu,Yifei Wang,Yu Ho Kwok,Wending Pan,Wai Szeto,Haibao Huang,Dennis Y.C. Leung
The particular role of fluorine (F) doping in the photocatalytic activity of nanocrystalline titanium dioxide (TiO 2 ) towards toluene degradation was systematically studied. TiO 2 nanosheet catalysts doped with different amounts of F − (denoted by F-TiO 2 ) were synthesized by hydrothermal method. For comparison, calcination was performed on the catalyst to remove F - . The photocatalytic oxidation (PCO) of toluene over F-TiO 2 was found to be much higher than those of TiO 2 and commercial P25 under the irradiation of vacuum ultraviolet (VUV) light, with a high toluene degradation efficiency of about 90 %. Moreover, the toluene degradation efficiency increased to 96 % with the addition of only 1 wt.% α-MnO 2 nanowires, and the residual ozone (O 3 ) in the system can be completely eliminated. In addition, four different substrates were explored for catalyst coating to facilitate the operation and minimize catalyst loading, which can provide a promising strategy for practical volatile organic compounds (VOCs) abatement in industrial applications.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Jinhua Lai,Feng Cheng,Shuolin Zhou,Sha Wen,Dongwen Guo,Wenguang Zhao,Xianxiang Liu,Dulin Yin
Nitrogen-containing polymer-supported Cu-doped MnO 2 (Cu-MnO 2 @PDVTA) nanowires were prepared and their catalytic performances were evaluated via oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA). The Cu-MnO 2 @PDVTA catalysts were characterized by Fourier-transform infrared spectroscopy, X-ray diffraction, N 2 physical adsorption, transmission electron microscopy, and X-ray photoelectron spectroscopy. Both the Cu 2+ and MnO 2 nanoparticles were found to synergistically promote HMF oxidation to FDCA via 2,5-furandicarbaldehyde and 5-formyl-2-furancarboxylic acid intermediates. The Cu-MnO 2 @PDVTA-3 catalyst demonstrated the highest catalytic activity, providing FDCA with an excellent yield of 96.8% after 12 h at 80 °C. The time course of HMF oxidation revealed that oxidation of the hydroxyl group in HMF was easier than that of the aldehyde group. Cu-MnO 2 @PDVTA-3 could act as a reusable heterogeneous catalyst for HMF oxidation.
研究领域:
化学工程
·
材料科学
·
催化反应
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）