Nanomaterials
·
2023
·Vol. 13
·期 21
·2894
·
IF 5.3
Fang Zhou,Weichang Zhou,Yujing Zhao,Li Liu
Bi2Te3has been extensively used because of its excellent thermoelectric properties at room temperature. Here, 230–420 nm of Bi2Te3hexagonal nanosheets has been successfully synthesized via a “green” method by using ethylene glycol solution and applying polyvinyl pyrrolidone (PVP) as a surfactant. In addition, factors influencing morphological evolution are discussed in detail in this study. Among these parameters, the reaction temperature, molar mass of NaOH, different surfactants, and reaction duration are considered as the most essential. The results show that the existence of PVP is vital to the formation of a plate-like morphology. The reaction temperature and alkaline surroundings played essential roles in the formation of Bi2Te3single crystals. By spark plasma sintering, the Bi2Te3hexagonal nanosheets were hot pressed into solid-state samples. We also studied the transport properties of solid-state samples. The electrical conductivityσwas 18.5 × 103Sm−1to 28.69 × 103Sm−1, and the Seebeck coefficientSwas −90.4 to −113.3 µVK−1over a temperature range of 300–550 K. In conclusion, the observation above could serve as a catalyst for future exploration into photocatalysis, solar cells, nonlinear optics, thermoelectric generators, and ultraviolet selective photodetectors of Bi2Te3nanosheet-based photodetectors.
研究领域:
材料科学
·
纳米技术
·
能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2020
·Vol. 10
·期 23
·8086-8093
·
IF 5.721
Haoxi Jiang,Debin Kong,Ying Niu,Sheng Wang
MnO2–CoOX catalysts with different Mn/Co ratios were prepared using polyvinyl pyrrolidone (PVP) as an assistant to control the morphology and exposed crystal faces of composite oxides. The physicochemical properties of the catalysts were systematically characterized and the catalytic activity of NH3-SCR and resistance to SO2/H2O were investigated. It was found that the NO conversion over Mn–Co-0.2-PVP was apparently higher compared with that over Mn–Co-X-PVP (X = 0.9, 0.8, 0.6, and 0.4). This can be interpreted in terms of exposed crystal surface (110) and enhanced adsorption of NH3/NO, and better redox performance resulting from higher Co3+/Co2+ ratio. Furthermore, different PVP and HAc additives have different H2O and SO2 resistance. Mn–Co-0.2-PVP showed good resistance to H2O and SO2 poisoning owing to having more low-temperature (∼200 °C) NO adsorption sites, which are beneficial to promote the de-NOX reaction and less affected by SO2.
研究领域:
环境科学
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2017
·
IF 5.401
Zaihua Duan,Min Xu,Tingshuai Li,Yong Zhang,Hefeng Zou
La 0.7 Sr 0.3 MnO 3 (LSMO) nanocrystals were prepared by polyvinylpyrrolidone (PVP)-assisted sol-gel method and characterized by a variety of characterization techniques. The humidity sensor based on LSMO nanocrystals was fabricated and its humidity sensing properties were investigated at room temperature (25 °C) within the relative humidity (RH) range of 11–95%. The optimum working frequency of the LSMO humidity sensor was 10 Hz and the impedance variation was about four orders of magnitude within the whole humidity range from 11% to 95% RH. The LSMO humidity sensor was of super-fast response speed, which was only about 0.8 s from 11% to 95% RH at 10 Hz. The super-fast response property may be ascribed to the strong hydrophilicity of LSMO nanocrystals. In addition, the LSMO humidity sensor was of good reproducibility, stability, small humidity hysteresis (4% RH at 75% RH) and a fast recovery speed (∼4.9 s). These results indicate the LSMO nanocrystals can be used as a novel humidity sensing material to fabricate high performances humidity sensors.
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2017
·
IF 3.752
Huan Liu,Quanzhen Liu,Jianzhong Zhang,Changlong Yin,Yuxin Zhao,Shumeng Yin,Chenguang Liu,Wanfu Sun
The effect of polyvinyl pyrrolidone (PVP) on the physicochemical properties and catalytic activities of unsupported NiMo catalysts was studied. The NiMo catalyst precursors were synthesized by a PVP-assisted chemical precipitation method, by adding various contents of PVP to a Ni- and Mo-containing solution. A series of techniques, including CHSN analysis, XRF , XRD, N 2 adsorption-desorption, FT-IR, SEM, TG-DSC, TPR, and XPS, were used to characterize the NiMo oxide precursors and sulfided catalysts, and the catalytic activities were tested in the hydrodesulfurization (HDS) of dibenzothiophene (DBT). The characterization results revealed that PVP was efficiently removed due to low contents in the synthesis and high solubility in water. The pore properties and hysteresis loop , the agglomeration of the nanoparticles , and the reducibility of the NiMo precursor were affected by the introduction of PVP, while the phases of the precursors and the thermal stabilities were little changed. Ni 3 S 2 and MoS 2 phases were observed in the sulfided catalysts. The catalysis results revealed that the hydrogenation pathway was predominant in the HDS of DBT. A NiMo catalyst synthesized with 0.5 g PVP showed a higher conversion of DBT than the other NiMo catalysts, possibly due to efficient formation of the ‘NiMoS’ active phase. This facile, scalable, and cost-effective route to prepare unsupported NiMo catalyst with enhanced HDS activities would be attractive in industrial applications.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
Applied Nanoscience
·
2020
·Vol. 10
·期 6
·1845-1851
·
IF 2.88
Wang Tianxiong,Jiang Tiancai,Meng Xianquan
We found that the morphology of nanowires could be regulated by adding polyvinylpyrrolidone (PVP, K30) in hydrothermal synthesis of antimony sulfide (Sb 2 S 3 ) nanowires. The nanowires with length more than 20 μm were obtained by adding the proper amount of PVP. Three kinds of fully nanostructured photodetector using Sb 2 S 3 nanowires as active regions were fabricated and the first detector used silver nanowires as the electrodes at both ends, the second used silver nanowires as one electrode and MXenes as the another electrode, and the third used MXenes as both electrodes. The light response speed of the photodetector with both MXenes electrodes was improved greatly. The photodetector which used MXenes and silver nanowires as electrodes at two ends, respectively, showed the phenomenon of being self-driven. The mechanism of asymmetric hole migration was put forward to explain the effect of being self-driven.
研究领域:
材料科学
·
纳米技术
·
光电子学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2021
·Vol. 96
·期 8
·2298-2309
·
IF 3.174
Shizi Luo,Xinyan Xiao,Yi Wang,Mingli Lu
BACKGROUND The commonly used RhB dye is a carcinogen that is widely found in environmental matrices and poses a threat to aquatic biota and human health. However, conventional wastewater treatment processes do not effectively remove low concentrations of these pollutants. Herein, the P-Bi 4 O 5 Br 2 /AgI (PBA) heterojunction was synthesized via a polyvinylpyrrolidone (PVP)-assisted solvothermal and precipitation method in this work. RESULTS The photocatalytic efficiency of the PBA heterojunction was evaluated by degrading rhodamine B (RhB) with the irradiation of simulated sunlight. P-Bi 4 O 5 Br 2 /AgI-50 (PBA-50, the mass fraction of AgI in the composite was 50%) composite could degrade 98% RhB under 90 min irradiation of 500 W Xenon lamp, and its pseudo first-order reaction rate constant was 0.04265 min −1 , which was 17.1, 2.16, and 2.94 times higher than that of Bi 4 O 5 Br 2 , P-Bi 4 O 5 Br 2 , and AgI, respectively. Besides, the effects of the dosage of photocatalyst and the anion on the photocatalytic degradation of RhB over PBA-50 were analyzed. CONCLUSION The enhanced photocatalytic activity of PBA was attributed to its better visible light capture ability, larger specific surface area, and faster photogenerated carrier separation efficiency, all of which were confirmed by scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), UV-Vis diffues reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), and photoelectrochemical analysis. In addition, the free radical trapping experiments confirmed that ·O 2 − and h + were the main active species for degradation of RhB. Additionally, the smaller bandgap and the more negative conduction band position of Bi 4 O 5 Br 2 were reached after the introduction of PVP. Accordingly, a possible type-II heterojunction photocatalytic mechanism of P-Bi 4 O 5 Br 2 /AgI was proposed. © 2021 Society of Chemical Industry (SCI).
研究领域:
环境科学
·
材料科学
·
光催化技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2020
·
IF 7.246
Chengcheng Shi,Dachao Yuan,Luping Ma,Guangsheng Fu,Shufang Wang,Yaguang Li
Sunlight-driven toluene elimination system faces the problems of low reaction rate, secondary pollution, and especially tricky to large-scale production. In this work, we used a PVP assisted spray drying method to synthesize Cu doped CeO 2 microspheres with the merits of zero waste water and solids discharge, kilogram level yield, uniform dispersion of Cu, and high toluene combustion activity. Further, a new photothermal device was constructed to heat catalysts to 295 °C under one standard sunlight irradiation. As a result, the new photothermal device supported Cu doped CeO 2 microspheres showed a full oxidation of toluene at the rate of 59.82 mmol g −1 h −1 under 1 sun irradiation, 150 times higher than the advanced sunlight-driven toluene elimination. An industrial demonstration of this new system was developed, and this system was able to completely deal with 22.2 m 3 h −1 of exhaust with the toluene concentration of 1–10,000 ppm under 1 m 2 of outdoor sunlight irradiation in the daytime of winter, showing the potential on industrial applications.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2017
·Vol. 28
·期 24
·18542-18550
·
IF 2.019
Wu Huating,Ding Xingeng,Li Wenqi,Ren Chunrong,Yang Hui
In this study, a magnetic Fe 3 O 4 /SiO 2 /BiOBr composite photocatalyst was controllably synthesized a PVP-assisted solvothermal method. The Fe 3 O 4 /SiO 2 /BiOBr composites are composed of many three-dimensional (3D) flower-like BiOBr microspheres loaded with many spherical Fe 3 O 4 particles. The formation mechanism and effect of PVP’s concentration on the products were investigated and proposed. Experimental results showed that PVP might act as a potential crystal plane inhibitor in the system as well as the stabilizer on the surface of BiOBr nanoplates. The Fe 3 O 4 /SiO 2 /BiOBr displayed high photocatalytic activity for the degradation of RhB under visible light irradiation, after which it can be easily recovered by applying an external magnetic field. Moreover, the as-prepared photocatalyst exhibited excellent stability and reusability in the cycled experiments.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2016
·
IF 7.145
Zhouyue Lei,Wencheng Zhu,Shengjie Xu,Jian Ding,Jiaxun Wan,Peiyi Wu
A facile poly(vinylpyrrolidone) (PVP)-assisted exfoliation method is utilized to simultaneously exfoliate and noncovalently modify MoSe2 nanosheets. The resultant hydrophilic nanosheets are shown to be promising candidates for biocompatible photothermal therapy (PTT) agents, and they could also be encapsulated into a hydrogel matrix for some intelligent devices. This work not only provides novel insights into exfoliation and modification of transition metal dichalcogenide (TMD) nanosheets but also might spark more research into engineering multifunctional TMD-related nanocomposites, which is in favor of further exploiting the attractive properties of these emerging layered two-dimensional (2D) nanomaterials.
研究领域:
材料科学
·
纳米技术
·
生物医学工程
·
诊疗学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2022
·Vol. 169
·期 6
·060547
·
IF 4.386
Ruixiang Wang,Yanyang Wang,Zheqin Chen,XiaoCong Zhong,Yongmin Xie,Xiaobo Ji,Jiaming Liu,Shubiao Xia,Zhifeng Xu
Transition metal/nitrogen carbon composite (M/NC) is a highly active oxygen reduction reaction (ORR) electrocatalyst, widely used in fuel cells and zinc-air batteries. Herein, a uniform and regular PVP-assisted iron-doped nano dodecahedron (ZP0.1F/NC) is prepared by a simple and efficient one-step in-solution reaction, followed by controlled in situ pyrolysis. The synthesized electrocatalyst showed excellent electrocatalytic ORR activity in an alkaline medium. Compared with standard 20% Pt/C electrocatalyst, ZP0.1F/NC exhibited onset potential (Eonset) (0.974 V vs 0.967 V), half-wave potential (E1/2) (0.861 V vs 0.857 V) and the limiting current density (jd) was 6.373 mA cm−2 vs 5.401 mA cm−2, also better than the Fe doped ZIF-8 nitrogen composite (ZF/NC), PVP auxiliary ZIF-8 (ZP0.1/NC) and pure ZIF-8 nitrogen composite (Z/NC) synthesized by the same procedure. In addition, the zinc-air battery assembled with ZP0.1F/NC also exhibits outstanding discharge capacity, with a specific capacity and energy density of 793.3 mAh g−1 and 974.9 Wh kgZn−1, respectively, much higher than that of commercial 20% Pt/C-based zinc-air battery (719.8 mAh g−1, 842.6 Wh kgZn−1), indicating its great potential in practical energy conversion and storage.
研究领域:
材料科学
·
电化学
·
能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）