APPLIED SURFACE SCIENCE
·
2010
·Vol. 257
·期 9
·3920-3923
·
IF 1.616
Hongxu Guo,Jianhua Chen,Wen Weng,Shunxing Li
A visible light-driven photocatalyst, C-doped Zn 3 (OH) 2 V 2 O 7 , prepared by a hydrothermal method was studied. The as-prepared catalyst was characterized by SEM, XRD , DRS, and XPS , and exhibited efficient photocatalytic activity in the degradation of methylene blue (MB) under visible-light irradiation. Besides decoloring, the decomposition of MB was also observed, further demonstrating the performance of the photocatalyst. The carbon existing on the surface of Zn 3 (OH) 2 V 2 O 7 nanorods was free and in carbide form. Dye degradation followed first-order kinetics, and was explained on the basis of the Langmuir–Hinshelwood mechanism.
研究领域:
材料化学
·
光催化
·
纳米材料
·
环境化学
·
无机合成
✓ 已验证
DOI
高影响因子
Small
·
2019
·Vol. 15
·期 12
·1805474
·
IF 10.856
Yi Jiang,Xingqiao Wu,Yucong Yan,Sai Luo,Xiao Li,Jingbo Huang,Hui Zhang,Deren Yang
Developing an efficient electrocatalyst for the hydrogen evolution reaction (HER) working in both acidic and alkaline solutions is highly desirable, but still remains challenging. Here, Pt x Ni ultrathin nanowires (NWs) with tunable compositions ( x = 1.42, 3.21, 5.67) are in situ grown on MXenes (Ti 3 C 2 nanosheets), serving as electrocatalysts toward HER. Such Pt x Ni@Ti 3 C 2 electrocatalysts exhibit excellent HER performance in both acidic and alkaline solutions, with the Pt 3.21 Ni@Ti 3 C 2 being the best one. Specifically, Pt 3.21 Ni@Ti 3 C 2 achieves record-breaking performance in terms of lowest overpotential (18.55 mV) and smallest Tafel slope (13.37 mV dec −1 ) for HER in acidic media to date. Theory calculations and X-ray photoelectron spectroscopy analyses demonstrate that the coupling of MXenes with the NWs not only approaches the Gibbs free energy for hydrogen adsorption close to zero through the electron transfer between them in acidic media, but also provides additional active sites for water dissociation in alkaline solution, both of them being beneficial to the HER performance.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源材料
·
物理化学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2015
·Vol. 36
·期 2
·204-208
·
IF 1.964
Zhongkui Zhao,Renzhi Li,Yu Li,Guiru Wang
A clean and highly efficient catalytic aerobic reductive ring-cleavage of 3–methylanthra[1,2- c ]isoxazole-6,11-dione to 1-amino-2-acetylanthraquinone was performed using simple organic amines as organocatalysts and water as a green reaction medium. This method provides a new clean transformation of isoxazole-containing compounds to the corresponding ortho -amino ketones . The catalytic performance of various organic amines was carefully screened, and simple organic primary amines were found to be promising practical catalysts with outstanding catalytic performance. Isopropylamine as the organocatalyst gave 97.2% conversion of 3–methylanthra[1,2- c ]isoxazole-6,11-dione, with 97.2% selectivity to 1-amino-2–acetylanthraquinone, in the presence of oxygen only, using 1 equiv. of hydrazine hydrate at room temperature for 3 h. A possible mechanism is also proposed.
研究领域:
有机化学
·
催化化学
·
绿色化学
·
药物化学
·
合成方法学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Xingchao Zhang,Ruoyu Zhang,Siying Niu,Jiming Zheng,Chongfeng Guo
The MoS 2 /g-C 3 N 4 heterojunction composite (marked as MoS 2 /g-C 3 N 4 -H) was successfully prepared via calcining the melamine coated MoS 2 nano-sphere, where the thin g-C 3 N 4 nano-sheets were tightly grown on the surface of MoS 2 nano-sphere to form MoS 2 inlaying in g-C 3 N 4 heterostructure. The detailed charge transfer mechanism was discussed by combining theoretical calculation and experiments, in which the intrinsic cause of photo-generated charge separation and transfer was determined as the directional built-in electric field driven by different Fermi levels of MoS 2 and g-C 3 N 4 . Comparatively, the enhanced photo-catalytic performance and stability of the sample were assessed by degrading the Rhodamine (RhB) and reducing the Dichromate (Cr 6+ ) solutions under the irradiation of the simulated sunlight, which could be attributed to the widened spectral absorption range and improved electron-hole separation rate. Based on above results, the photo-catalytic mechanism involving redox reactions was also clearly proposed.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Sustainable Energy & Fuels
·
2017
·Vol. 2
·期 2
·444-454
·
IF 0
Xiaohong Xia,Chunming Wang,Lang Liu,Yonglin Du,Weichun Ye
Transition metal dichalcogenides for electrocatalytic water splitting are important in renewable energy research, with studies showing that the edge structure and specific surface area are crucial to their electrocatalytic activity. Herein, the design and construction of yolk–shell nanospheres based on molybdenum diselenide-encapsulated molybdenum oxide are reported. Their structures were characterized using various techniques, which showed that the void space between the interior core and outer shell increased the number of active sites. This yolk–shell structure exhibited enhanced and stable electrocatalytic activity in the hydrogen evolution reaction (HER). The HER current density at −0.5 V vs. the reversible hydrogen electrode was increased by 95% (to −256 mA cm−2) compared to that of traditional flower-like molybdenum diselenide. The overpotential of this yolk–shell structure, which was required to drive a current density of −10 mA cm−2, was 65 mV lower than that of flower-like molybdenum diselenide (286 mV). Furthermore, long-term potential cycling and potentiostatic measurement of this catalyst showed favorable stability and durability of electrocatalytic activity. This yolk–shell structure plays a key role in energy conversion processes central to several renewable energy technologies.
研究领域:
材料科学
·
纳米科技
·
电化学
·
能源化学
·
催化化学
✓ 已验证
DOI
Materials Science & Engineering C-Materials for Biological Applications
·
2012
·Vol. 32
·期 6
·1699-1703
·
IF 2.686
Jing Ma,Hou Chen,Min Zhang,Chunhua Wang,Ying Zhang,Rongjun Qu
Yb-based catalyst was used for the first time for atom transfer radical polymerization using activators generated by electron transfer (AGET ATRP) of acrylonitrile (AN) with 2-bromopropionitrile (BPN) as initiator, 2, 2′-bipyridine (bipy) as ligand, and tisn(II) bis(2-ethylhexanoate) (Sn(EH) 2 ) as reducing agent in the presence of air. With respect to AGET ATRP of AN catalyzed by CuBr 2 , an evident increase of polymer tacticity was observed for AGET ATRP of AN. The increase of syndiotacticity became more and more pronounced than the increase of isotacticity of polyacrylonitrile (PAN) along with YbBr 3 content. The block copolymer PAN-b-PMMA with molecular weight at 60,000 and polydispersity at 1.36 was successfully prepared.
研究领域:
高分子化学
·
材料科学
·
催化化学
·
聚合物合成
·
功能材料
✓ 已验证
DOI
高影响因子
Journal of Nanomaterials
·
2019
·Vol. 2019
·期 1
·2769519
·
IF 2.233
Hongchong Guo,Wei Li,Gang Sun,Bo You
We propose a facile and simple synthesis of photoluminescent (PL) carbon dot self-assembled monolayer films (CD-SAMFs) at oil-water interfaces. By using styrene both as the carbon source and the oil phase medium, we got our amazing CD-SAMFs under the copper acetate and hydrogen peroxide (Cu(Ac) 2 -H 2 O 2 ) catalytic-oxidation system. Without any surface modification, the spontaneously formed CD-SAMFs exhibit ultrathin thickness (<10 nm), bright luminescence, high transparency, and hydrophobicity, which have the potential as a new alternative to be used on multifunctional coating films, anticounterfeiting, displays, sensors, and optical devices.
研究领域:
材料科学
·
纳米科技
·
表面化学
·
光电子学
·
功能薄膜
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC
·
2016
·
IF 2.189
Chen Chen,Xue-yan Zhu,Qiao-ling Gao,Fei Fang,Li-wei Wang,Xiao-jun Huang
Functional polyphosphazene cyclomatrix microspheres (PMS) containing glucose and dodecyl moieties were utilized for physical adsorption of lipase. In this regard, Candia Rugosa lipase was immobilized onto the above microspheres through physical adsorption, which exhibited catalytic hydrolysis of glycerol triacetate as the model reaction. As observed under transmission electron microscope (TEM) and scanning electron microscope (SEM), the size of all the microspheres ranged from 400 nm to 1 μm with a mean diameter of 680 nm. Zeta potential analysis demonstrated that the microspheres were negatively charged. The influences of buffer pH, substrate concentration and temperature were also studied along with reusability. The obtained results demonstrated that the immobilized lipase on deprotected glycosylated PMS (D-GPMS) showed the best performance and possessed the highest enzymatic loading activity around 1.0884 mmol L −1 min −1 g −1 , and retained nearly 50% of its initial activity even after 10 cycles of application. Moreover, the lipase-microsphere complex displayed high pH adaptability from 7 to 9 and temperature stability above 40 °C. From the viewpoint of biocompatible PMS support, the GPMS-lipase conjugate have potential applications in field such as food, medicine and environment.
研究领域:
生物材料
·
酶工程
·
纳米医学
·
分子生物学
·
环境生物技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
·
2016
·
IF 3.958
Lei Zhao,Baoyue Zhang,Xin Xiao,Feng Long Gu,Rui-Qin Zhang
Active species such as holes, electrons, hydroxyl radicals ( OH), and superoxide radical anions ( O 2 − ) involved in the photocatalytic oxidation of benzyl alcohol (BA) into benzaldehyde (BAD) on TiO 2 under ultraviolet (UV) light were investigated by adding corresponding scavengers. The experimental results show that the oxidation of BA into BAD is driven mainly by the holes and OH radical. The role of dissolved O 2 was studied by bubbling N 2 through the reaction. The results show that the dissolved O 2 is, to some extent, the source of OH. Additional density functional theory (DFT) calculations identified two H-abstraction pathways ( R abs OH and R abs α). The structure of the R abs OH product is less stable and tends to transfer resulting in the R abs α product. The holes are the main driving force for the abstracting of H from BA. The OH radical combines with the H-abstract product to form a precursor of product BAD, detected by LC–MS technique ( m / z 123), which then undergoes an intramolecular dehydration reaction to form BAD. The results will help to select the optimal active species for the photocatalytic oxidation of BA into BAD on TiO 2 under UV light.
研究领域:
物理化学
·
光催化
·
环境化学
·
材料化学
·
理论计算化学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2017
·
IF 9.446
Hui He,Xueting Lin,Shujun Li,Zeng Wu,Jingheng Gao,Junliang Wu,William Wen,Daiqi Ye,Mingli Fu
Surface species and oxygen vacancies were studied in MnO x (0.4)-CeO 2 toward repeated soot oxidation. MnO x (0.4)-CeO 2 catalysts prepared by the citric acid complex method were repeatedly used in a 10% O 2 /Ar gas flow and showed favorable activity and satisfactory durability toward soot oxidation. X-ray diffraction (XRD), N 2 adsorption/desorption, Electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS) and in situ visible/UV Raman characterization methods were utilized to investigate the structural features of fresh and reused catalysts. The irreversible conversion of high valence manganese species as well as the reduction of Frenkel-type oxygen vacancies and lattice oxygen could be clearly observed in the reused samples, which were associated with the slight deactivation. Spectators and participators were two existing forms of Frenkel-type oxygen vacancies. It was noteworthy that the participators almost fully regenerated after each reaction cycle, which ensured the ability to activate O latt in repeated soot oxidation process. Therefore, the catalysts maintained favorable activity and satisfactory durability, which was mainly because the relatively stable level of participators.
研究领域:
催化化学
·
环境催化
·
材料化学
·
表面科学
·
能源化学
✓ 已验证
DOI
高影响因子
MATERIALS & DESIGN
·
2017
·
IF 4.364
Puhong Wen,Lili Ai,Taotao Liu,Dengwei Hu,Fangyi Yao
The regular orthorhombic Nb 2 O 5 (O-Nb 2 O 5 ) rectangle nanosheets dominantly exposed (010) facet are synthesized by a hydrothermal topological reaction with a precursor of K 4 Nb 6 O 17 ·4.5H 2 O (KNbO). The structure and morphology of the samples obtained at different temperatures and pH values of reacting solution are investigated. The results suggest that there are two topological reactions in this process. One is the acid-exchanging reaction transforming into H 4 Nb 6 O 17 ·3H 2 O (HNbO) nanosheets from KNbO rectangle nanosheets , and the other is dehydration reaction transforming into O-Nb 2 O 5 rectangle nanosheets from HNbO nanosheets. And the {010} facets of O-Nb 2 O 5 crystal are transformed from the {010} facets of HNbO crystal in the ingenious topological reaction. The photoelectric performance of the obtained O-Nb 2 O 5 nanosheets is evaluated by decomposing water to H 2 under 370 nm UV light illumination and measuring the accompanying photocurrent . The photocurrent density is 680 nA·cm − 2 generated by splitting water with O-Nb 2 O 5 nanosheets as photocatalyst , and it is 4.3 times of the contrast sample. The result indicates that the (010) facet of O-Nb 2 O 5 is one of the highest photocatalytic active surfaces and shows high photoelectric conversion efficiency. Thus, the O-Nb 2 O 5 nanosheets dominantly exposed (010) facet have potential applications in photocatalyst and photoelectric nanodevices .
研究领域:
材料科学
·
光催化
·
纳米材料
·
无机化学
·
能源材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
·
IF 4.65
Zhuangzhi Wu,Min Ouyang,Dezhi Wang,Xinli Liu
The photoelectrocatalytic water splitting of molybdenum disulfide is hindered by the intrinsic large electrical resistance among adjacent layers, serious photo-generated carrier recombination and limited utilization of visible light . Herein, we construct MoS 2 /MoO 2 heterostructures via a facile in situ hydrothermal route, in which a Schottky junction is established between the MoS 2 semiconductor and metallic MoO 2 . As a result, the photoelectrochemical current density of MoS 2 /MoO 2 is enhanced about 1.6 times than that of pure MoS 2 , achieving −10.3 mA cm −2 at −1.8 V vs. SCE, which can be attributed to the reduced electron transfer resistance, enlarged photo-generated carrier separation efficiency and enhanced light absorption due to the presence of metallic MoO 2 .
研究领域:
材料科学
·
物理化学
·
能源化学
·
半导体催化
·
光电子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）