JOURNAL OF RARE EARTHS
·
2017
·
IF 2.429
Song LI,Song YE,Xiao CHEN,Tianhua LIU,Zhuang GUO,Deping WANG
Yb 3+ and Er 3+ ions co-doped NaYF 4 nanocrystals were synthesized with different amounts of NaOH via oleic acid (OA)-assisted hydrothermal process. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and photoluminescence spectra were used to characterize the products. The result indicated that the introduction of NaOH into the initial reaction solution effectively promoted the cubic (α-) to hexagonal (β-) phase transition of NaYF 4 :Yb 3+ ,Er 3+ nanocrystals, while excessive amount of NaOH favored the formation of α-NaYF 4 :Yb 3+ ,Er 3+ nanocrystals. Besides, with the increase of NaOH amount, the morphologies of β-NaYF 4 :Yb 3+ ,Er 3+ nanocrystals varied from irregular nanobranch to uniform nanorod. Further investigation revealed that the addition of NaOH could facilitate the deprotonation of OA, leading to the formation of oleate (OA − ), and meanwhile increased the concentration of OH − ions, inducing consequently the phase transition and morphology evolution of NaYF 4 :Yb 3+ ,Er 3+ nanocrystals. Moreover, the upconversion luminescence properties of NaYF 4 :Yb 3+ ,Er 3+ nanocrystals were systematically investigated. It was found that the upconversion emissions not only depended on the phase and morphology but also were influenced by the surface groups.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Yongfang Jia,Juan Gao,Feng Yang,Yangmin Diao,Qijun Liu,Yong Zhang,Hongliang Sun,Min Pan,Mei Huang,Min Xu,Xuru Duan,Yong Zhao
Despite the excellent performance of Nb3O7(OH) in dye-sensitized solar cells and catalysis, its charge separation, transport, and structural properties remain poorly understood. Herein, the Nb3O7(OH) nanorods were prepared, and their structural characteristics, optoelectronic properties, and carrier mobility were also analyzed and investigated through a series of complex characterizations. Theoretical prediction suggested that the exciton binding energy of Nb3O7(OH) could be as high as 100.49 meV. The temperature-dependent photoluminescence (PL) of Nb3O7(OH) nanorods revealed two activation energies, and a higher proportion of long-lived components observed in the photoluminescence decay indicated effective electron trapping. That is, two energy states were present, hindering photogenerated charge recombination and promoting photocatalytic action. Current–voltage characteristics of the Nb3O7(OH) nanorod film were analyzed, revealing an ultrahigh carrier mobility of ∼310 cm2/V·s, ensuring fast and efficient electron transfer. Furthermore, Nb3O7(OH) nanorods were employed to reduce CO2, resulting in the effective production of CO and CH4. Overall, considering the presence of hydroxyl pairs on the surface of Nb3O7(OH), which facilitate the formation of the frustrated Lewis acid–base pairs and the activation of CO2, together with its effective electron trapping and charge transport, give Nb3O7(OH) nanorods a promising potential for CO2 reduction.
研究领域:
材料科学
·
催化化学
·
光电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2014
·Vol. 16
·期 9
·1-9
·
IF 2.278
Cui Hongtao,Xue Junying,Ren Wanzhong,Wang Minmin
In this work, β-Ni(OH) 2 monolayer nanosheets were prepared in benzyl alcohol by a facile exfoliation-free sol–gel route. The hydrolysis reaction of metal ions was started with the ring-opening reaction of epoxide. The in situ modification of benzyl alcohol molecules on the surface of secondary growth unit of hydroxide allowed the formation of β-Ni(OH) 2 monolayer nanosheets and 100 % monolayer state of β-Ni(OH) 2 in the resultant suspension. As proven in the electrochemical measurement, the maximum specific capacitance of 1735 F g −1 was obtained at scan rate of 5 mV s −1 within potential window of 0.6 V in 6 mol l −1 KOH aqueous solution, which is equal to the theoretical value of β-Ni(OH) 2 . This high electrochemical performance is attributed to the complete exposure of every structure unit of β-Ni(OH) 2 to electrolyte. This work demonstrates that monolayer nanosheets can generate from the brucite-type nickel hydroxide through this bottom-up strategy although it had been theoretically considered to be impossible.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2012
·Vol. 4
·期 7
·2423-2430
·
IF 5.914
Qing Cao,Feng Huang,Zanyong Zhuang,Zhang Lin
This work aims at the investigation of nano-Mg(OH)2 as a promising adsorbent for uranium recovery from water. Systematic analysis including the uranium adsorption isotherm, the kinetics and the thermodynamics of adsorption of low concentrations of uranyl tricarbonate (0.1–20 mg L−1) by nano-Mg(OH)2 was carried out. The results showed a spontaneous and exothermic uranium adsorption process by Mg(OH)2, which could be well described with pseudo second order kinetics. Surface site calculation and zeta potential measurement further demonstrated that UO2(CO3)34− was a monolayer adsorbed onto nano-Mg(OH)2 by electrostatic forces. Accordingly, the adsorption behavior met the conditions of the Langmuir isotherm. Moreover, in most of the reported literature, nano-Mg(OH)2 had a higher UO2(CO3)34− adsorption affinity b, which implied a higher adsorption amount at equilibrium in a dilute adsorbate system. The significance of the adsorption affinity b for choosing and designing adsorbents with respect to low concentration of resources/pollutants treatment has also been assessed.
研究领域:
环境科学
·
材料科学
·
放射化学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Environmental Sciences
·
2018
·
IF 3.12
Xiaole Zhao,Yingchun Su,Shubin Li,Yajun Bi,Xiaojun Han
Dyestuffs and heavy metal ions in water are seriously harmful to the ecological environment and human health. Three-dimensional (3D) flowerlike Fe(OH) 3 microspheres were synthesized through a green yet low-cost injection method, for the removal of organic dyes and heavy metal ions. The Fe(OH) 3 microspheres were characterized by thermal gravimetric analysis (TGA), Fourier transform infrared (FT-IR), and transmission electron microscopy (TEM) techniques. The adsorption kinetics of Congo Red (CR) on Fe(OH) 3 microspheres obeyed the pseudo-second-order model. Cr 6 + and Pb 2 + adsorption behaviors on Fe(OH) 3 microspheres followed the Langmuir isotherm model. The maximum adsorption capacities of the synthesized Fe(OH) 3 were 308, 52.94, and 75.64 mg/g for CR, Cr 6 + , and Pb 2 + respectively. The enhanced adsorption performance originated from its surface properties and large specific surface area of 250 m 2 /g. The microspheres also have excellent adsorption stability and recyclability . Another merit of the Fe(OH) 3 material is that it also acts as a Fenton-like catalyst. These twin functionalities (both as adsorbent and Fenton-like catalyst) give the synthesized Fe(OH) 3 microspheres great potential in the field of water treatment .
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2021
·
IF 6.057
Huazheng Yu,Yanhong Li,Aisheng Huang
Sialic acid (SA) is a crucial component of glycoproteins and glycolipids on the cellular membrane, which is essential for maintaining the function of cell membranes, such as cell recognition and communication. Simultaneously, sialic acid plays a significant role in many physiological and pathological processes. Hence, it is urgent to develop a simple and sensitive strategy for determining sialic acid. In this work, a new metal-organic framework called UiO-66-NH 2 @B(OH) 2 has been designed and synthesized for the recognition and detection of sialic acid. The boronic acid functional group in UiO-66-NH 2 @B(OH) 2 can bind to a diol moiety of the glycerol side chain of sialic acid, which will attenuate or even quench the fluorescence of UiO-66-NH 2 @B(OH) 2 , thus opening a new road to detect sialic acid. Based on the measurement results, sialic acid can be quantitatively measured in a linear range of 0.05–2.5 mmoL/L with the UiO-66-NH 2 @B(OH) 2 probe. The detection limit of sialic acid is as low as 0.025 mmol/L. Furthermore, the boronic-acid functionalized probe UiO-66-NH 2 @B(OH) 2 displays high sensitivity and high selectivity to recognize the sialic acid in mouse serum samples. Therefore, the developed UiO-66-NH 2 @B(OH) 2 can be used as a promising probe to identify and detect sialic acid in the practical application.
研究领域:
分析化学
·
生物化学
·
材料科学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2016
·
IF 4.803
Zijiong Li,Weiyang Zhang,Chunyan Sun,Zhifu Feng,Baocheng Yang
It has shown better electrochemical performance to use two dimensions (2D) nanomaterial nickel hydroxide nanosheets as electrode materials in energy storage research. However, when compared with carbon electrode material, the disadvantage of metal hydroxide is more obvious. In this study, we use Ni(OH) 2 /rGO composites (NGCs) synthesized by hydrothermal method as electrode materials to conduct an electrochemical property tests in 6 M KOH electrolyte solution . As a result, when current density of NGC 8 samples (the mass ratio of Ni(OH) 2 and graphene is 8:1) is 0.8 A g −1 , the largest specific capacitance of composites is 1862.2 F g −1 . What’s more, when the current density is 15 A g −1 , the capacitance only reduced to 91.6% after the constant current charge and discharge for 2000 cycles, which showed magnificent cycling stability. Further investigations, the 2D nanomaterial NGCs can be easily transmitted to NrCs (NiO/rGO composites), and delivers a specific capacitance of 782.5 F g −1 at a current density of 0.5 A g −1 . These works are of great significance for the research of energy storage materials and the development of energy storage device.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Zhichao Yu,Jingfeng Wang,Wei Cao,Chang Luo,Shanshan Wang,Zhijun Ding,Lei Guo,Zhihong Qiao,Puhong Wang
Metal oxide semiconductor (MOS) gas sensor is an effective tool for NO 2 detection. In this work, a NO 2 sensor based on MXene-OH/ZnMnO was fabricated via a seed layer induced self-assembly method, exhibiting remarkable gas response value(280) to 100 ppm NO 2 under 25℃ and ultraviolet activation. Besides, the prepared sensor presents ultra-fast response and recovery speeds (8/40 s), low detection limit (250 ppb), and high selectivity. The enhanced sensing performance was explained by the first-principles calculations, showing that the increased electrical conductivity, more electron transfer numbers and higher adsorption energy promotes effective transport of charge carriers on the surface of sensing materials and NO 2 gas molecules.
研究领域:
材料科学
·
环境监测
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2016
·
IF 3.205
Jianmin Chen,Qilu Yao,Jia Zhu,Xiangshu Chen,Zhang-Hui Lu
Bimetallic Rh–Ni nanoparticles (NPs) immobilized on the cerium hydroxide carbonate (Ce(OH)CO 3 ) have been successfully prepared by a facile co-reduction route, and characterized by XRD , SEM , TEM , EDX, ICP , XPS , and TG-DTA. The as-synthesized Rh–Ni/Ce(OH)CO 3 nanocomposites (NCs) with different metal compositions were applied as the highly efficient catalysts for hydrogen generation from the alkaline solution of hydrazine (N 2 H 4 ). Especially, the Rh 55 Ni 45 /Ce(OH)CO 3 NCs exerted the highly activity and 100% H 2 selectivity for the decomposition of hydrazine, providing high turnover frequency (TOF) values of 150 h −1 at 30 °C and 395 h −1 at 50 °C, respectively, relative high values for the metal catalysts . The activation energy for the decomposition of hydrazine catalyzed by Rh 55 Ni 45 /Ce(OH)CO 3 NCs was measured to be 38.8 kJ/mol, lower than most of the values reported for this reaction using many different catalysts. This excellent catalytic performance could be attributed to not only the strain and ligand effects between Rh and Ni, but also the strong interaction between RhNi NPs and Ce(OH)CO 3 support. Such a highly catalyst may greatly encourage the practical application of hydrazine as a hydrogen storage material.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
NANOTECHNOLOGY
·
2020
·Vol. 31
·期 37
·374003
·
IF 3.551
Xitong Liang,Dongfeng Xue
Novel electrode materials with desired specific capacitances are needed for supercapacitors. Rare-earth (RE)-based materials are fascinating in the field of catalysis and energy. Herein, a series of hydroxides including La, Ce, Pr and Nd was synthesized via in situ precipitation. Interestingly, only Ce(OH)3 showed a redox peak in both positive and negative ranges. The other RE hydroxides exhibited a redox peak only in the positive range. Therefore, in order to certify that Ce(OH)3 can be used as a negative electrode, symmetrical supercapacitors consisting of Ce(OH)3 as both positive and negative electrodes were assembled, and showed a voltage window of 1.3 V. Moreover, asymmetrical supercapacitors were successfully fabricated, in which the positive electrode was composed of La(OH)3, Pr(OH)3 or Nd(OH)3. These results may pave the way to novel negative electrode materials.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Jiao Chen,Hongye Qin,Yaping Pan,Jinli Wu,Jianan Liu,Wanying Lin,Jun Jiang,Enzuo Liu,Junwei Sha,Fang He,Liying Ma,Naiqin Zhao
It is necessary and challenging to develop platinum-based electrocatalysts with low Pt content and high performance for industrial development in a suitable strategy. Herein, ultralow Pt (0.35 wt%) loading Ni(OH) 2 nanosheets (named as 2-Pt/Ni(OH) 2 ) with cataphracted structure is synthesized on nickel foam by one-step hydrothermal process. It only needs an overpotential of 34 mV to achieve a current density of 10 mA cm -2 without any significant decrease for 40 hours. This excellent performance of hydrogen evolution reaction (HER) is attributed to the fact that the cataphracted structure not only has a larger active area and more active sites, but also effectively limits the size of Pt nanoparticles to 2~3 nm, which results in a higher active quality. In addition, the relatively simple and easily operational one-step method can reduce the Pt content to 0.35 wt% significantly. This facile strategy opens up new approaches in the rational design and synthesis of low loading Pt electrocatalysts with eminent electrocatalytic activity for industrial production.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
APPLIED THERMAL ENGINEERING
·
2024
·
IF 6.1
Lisheng Deng,Shusen lin,Linfa Xiao,Mitsuhiro Kubota,Hongyu Huang,Jun Li,Dezhen Chen
The application of MgO/Mg(OH) 2 in heat storage technology has been limited due to slow hydration rate and easy agglomeration. In this paper, nanoporous carbon particle (NCP) as a carrier was used to prepare NCP/MgO chemical heat storage composite materials by impregnation and calcination methods, respectively. The microstructure characterization, hydration reaction, and simultaneous thermogravimetric analysis experiments were carried out on the prepared composite materials. The results showed that the internal distribution of MgO in the composite material prepared by calcination method was more uniform, and the particle size of MgO was smaller. Under the conditions of 110 ℃ hydration temperature and 57.8 kPa water vapor partial pressure, the hydration conversion ratio of the composite material prepared by calcination method after 120 min of hydration conversion ratio reached 93 %, which was 17.7 % higher than that of the impregnated composite material and 50 % higher than that of pure MgO. Under the comprehensive influence of specific surface area, pore structure, and active component particle size, compared with pure materials and impregnated composite materials, the dehydration rate of the composite material prepared by calcination method at 300 ℃ was twice that of impregnated method and 6 times that of pure MgO, and the heat storage density reached 1039kJ/kg. After 10 cycles, the heat storage density still maintained an initial state of 95.8 %. Compared with pure materials and impregnated composite materials, NCP/MgO composite materials prepared by calcination method had better heat storage performance and higher cyclic stability.
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
危险品化学品经营许可证（带存储）