INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2018
·
IF 3.141
Wei Bi,Yanjie Hu,Wenge Li,Hao Jiang,Chunzhong Li
In this work, a nanoreactor combining layers of facile traditional two-dimensional (2D) material, hexagonal boron nitride (h-BN, which often called the white graphene) with Pt/Al2O3 catalyst was designed to exhibit higher stability, activity, and selectivity in automobile exhaust treatment. Characterization revealed that h-BN does coat on the surface of platinum and forms a distinct Pt@h-BN/Al2O3 core–shell nanostructure. This as-prepared catalyst possesses good thermal stability and selectivity, because of the excellent high-temperature tolerance and the multidefected structure of the h-BN shell; that is, small molecules such as CO and O2 can easily intercalate into the nanoreactor, while large molecules such as propylene are blocked out. Meanwhile, the intercalated reactants can achieve the conversion of CO to CO2 faster (ΔT100 = 20 °C) with the confinement effect. The study indicates that constructing a nanoscale confined environment with two-dimensional (2D) coating can enhance the performance of the catalyst in multiple aspects and simultaneously provide a good example for designing nanostructured catalysts with multifaceted improvement.
研究领域:
催化化学
·
纳米材料科学
·
环境催化
·
能源化学
·
表面科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Chen Zhou,Hui Zhang,Jianian Cheng,Hongyi Li,Sadeh Beysen
Two new isostructural lead borates , Pb 8 Mg(BO 3 ) 6 and Pb 8 Ca(BO 3 ) 6 , have been synthesized via high temperature solution method. The single crystal structures of title compounds contain ∞ [Pb 8 B 6 O 18 ] 2- double layers composed of planar BO 3 triangles, Pb(2)O 9 and distorted Pb(1)O 5 polyhedra, these layers condense in c -axis, and the MgO 6 (or CaO 6 ) polyhedra fill into the layers, forming a three-dimensional framework. The stereochemical activity of lone pair (SCALP) electrons were found in the Pb(1)O 5 polyhedra, which combine with the BO 3 units, generating strong optical anisotropy . The calculated birefringences of Pb 8 Mg(BO 3 ) 6 and Pb 8 Ca(BO 3 ) 6 using first-principles method are 0.15@1064 nm and 0.12@1064 nm, respectively, which are comparable to the commercial α -BaB 2 O 4 (α-BBO) crystal and imply that they probably can be used as birefringent materials. The electronic structures, density of states of title compounds were calculated by density functional theory (DFT). Meanwhile, the TG-DSC curves, infrared spectral and UV–Vis–NIR diffuse reflectance spectral were measured.
研究领域:
无机化学
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材料科学
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晶体工程
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非线性光学材料
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固体化学
✓ 已验证
DOI
高影响因子
IEEE TRANSACTIONS ON ELECTRON DEVICES
·
2024
·Vol. 71
·期 10
·6417-6423
·
IF 2.9
Peng Yang,Yudong Pang,Jiajia Zha,Haoxin Huang,Zhendong Jiang,Meng Zhang,Chaoliang Tan,Wugang Liao
This article utilizes low-frequency noise (LFN) measurements to evaluate the stability of tellurium (Te) field-effect transistor (FET). Our results show that LFN for Te FET on hexagonal boron nitride/silicon dioxide (h-BN/SiO2) tracks the trends of flicker noise (1/f noise) and decreases with increasing overdrive voltages, which is ascribed to the change of dominant carriers and the fluctuation of surface trap density. Compared with Te FET on SiO2, Te FET on h-BN/SiO2 reaches a lower LFN. To further investigate the mechanism of current fluctuation, surface trap density ( ${N} _{\text {st}}$ ) is extracted. The average value of ${N} _{\text {st}}$ for Te FETs on h-BN/SiO2 is smaller than that for Te FETs on SiO2. It is concluded that the introduction of atomically flat h-BN dielectric decreases ${N} _{\text {st}}$ , suggesting that Te FET on h-BN/SiO2 presents higher immunity to LFN and provides a design thought for devices with high stability in the future.
研究领域:
半导体器件物理
·
微电子学
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凝聚态物理
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材料科学
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纳米电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2012
·
IF 2.289
Jiasong Zhong,Weidong Xiang,Haijun Zhao,Wenguang Zhao,Guoxin Chen,Xiaojuan Liang
Copper quantum dots embedded in sodium borosilicate glass matrix were fabricated and analyzed in terms of their structural, chemical, and optical properties. X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses revealed that copper quantum dots were in face-centered-cubic crystalline phase and in the metallic state. Size and distribution of the quantum dots were measured by transmission electron microscopy (TEM) as well as high-resolution transmission electron microscopy (HRTEM). The results showed spherical shape have formed uniformly in the glass, and the size of these quantum dots were range from 1.5 to 5 nm with the average particle size about 2.7 nm. The third-order nonlinear optical properties of copper quantum dots doped glass were investigated by using Z-scan technique at the wavelength of 800 nm with femtosecond Ti: sapphire laser radiation. The value of third-order optical nonlinear susceptibility χ (3) of the glass was estimated to be 2.41 × 10 −11 esu.
研究领域:
材料科学
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纳米科技
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光学材料
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凝聚态物理
·
无机非金属材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Zichuan Lu,Shuai Li,Tao Zhong,Ren Zhou,Fuying Wu,Daifen Chen,Wei Kong,Arkadii Proskurin,Liuting Zhang
s The development of heterostructure catalysts with high activity and reusability is of great significance for the green hydrogen production from NaBH 4 . In this paper, a novel CoNi-CoO x nanoparticle with Schottky heterostructure (UCC-30) was synthesized using a high-temperature annealing method. The successful preparation of catalysts with varying contents of CoO was achieved through the precise control of ultrasonication conditions. The experimental results demonstrated that the CoNi-CoO x catalysts exhibited remarkable catalytic performance and were capable of significantly reducing the activation energy for NaBH 4 hydrolysis, with an activation energy of 24.61 ± 0.51 kJ/mol. The hydrogen production rate (HGR) of NaBH 4 + UCC-30 reached 1245 mL min −1 g cat − 1 at 298 K, which was conspicuously higher than that of similar non-precious metal catalysts. Microstructural studies have demonstrated that CoNi-CoO x has a considerable catalytically active area in addition to Schottky moieties, which collectively contribute to the creation of multiple active sites, thereby improving the catalytic efficiency. Moreover, the catalytic capacity of NaBH 4 +UCC-30 remained at 81.9 % after five cycles at 298 K, indicating potential application in practical hydrogen production cases. It is noteworthy that the introduction of the Schottky structure can adjust the catalytic effect of CoNi alloy materials, thereby providing guidance for the future design and fabrication of efficient catalysts for hydrogen production and other energy related research areas.
研究领域:
材料科学
·
催化化学
·
能源化学
·
纳米材料
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可再生能源
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电化学
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表面科学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2017
·Vol. 35
·期 7
·1149-1156
·
IF 1.852
Xuejia Gao,Libo Niu,Xianliang Qiao,Wenhui Feng,Yingying Cao,Guoyi Bai
A novel NiB deposited layered double hydroxide (LDH) coated ferroferric oxide (Fe 3 O 4 @LDH@NiB) magnetic core-shell nanocomposite was successfully fabricated by the combination of coprecipitation and impregnation-reduction. During the Fe 3 O 4 @LDH preparation, a facile template-free approach was employed to introduce the LDH shell, which was more efficient than the conventional method for the preparation of mesoporous materials that always needs to introduce and remove templates. The resulted Fe 3 O 4 @LDH has a relatively high surface area and abundant surface hydroxyl group, which can adsorb metal ions, making it favorable to disperse and stabilize the active Ni species, as demonstraed by TEM, XPS, FT-IR and BET characterizations. Therefore, it exhibited good activity in the selective hydrogenation of cinnamic acid to hydrocinnamic acid with the conversion and selectivity both approaching to 100%. Notably, the obtained Fe 3 O 4 @LDH@NiB can be easily separated by an external magnetic field and recycled eleven times without appreciable loss of its initial catalytic activity.
研究领域:
材料化学
·
纳米催化
·
绿色化学
·
应用化学
·
功能材料
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2019
·
IF 4.084
Hailiang Chu,Nianpu Li,Xueying Qiu,Yu Wang,Shujun Qiu,Ju-Lan Zeng,Yongjin Zou,Fen Xu,Lixian Sun
In this work, poly( N -vinyl-2-pyrrolidone) (PVP)-stabilized ruthenium nanoparticles (NPs) supported on bamboo leaf-derived porous carbon (Ru/BC) has been synthesized via a one-step procedure. The structure and morphology of the as-synthesized samples were characterized by means of X-ray diffraction (XRD), X-ray photoelectron spectrometry (XPS), scanning electron microscope (SEM) and transmission electron microscope (TEM). As a catalyst for hydrogen generation from the hydrolysis of ammonia-borane (AB, NH 3 BH 3 ) at room temperature, Ru/BC stabilized with 1 mg of PVP exhibited high activity (TOF = 718 mol H2 ·mol Ru −1 ·min −1 ) and low activation energy ( E a = 22.8 kJ mol −1 ). In addition, the catalyst could be easily recovered and showed fairly good recyclability with 55.6% of the initial catalytic activity retained after ten experimental cycles, which confirmed that PVP could stabilize the Ru NPs and prevent their agglomeration on BC surface. Our results suggest that PVP-stabilized Ru/BC is a highly efficient catalyst for the hydrolysis of AB.
研究领域:
材料化学
·
催化化学
·
纳米材料
·
能源化学
·
绿色化学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 11
·3344-3350
·
IF 4
Wenhao Liu,Ming-Hsien Lee,Ruixin Guo,Jiyong Yao
Rare earth borates, a subset of the essential nonlinear optical (NLO) materials, have sparked a significant amount of attention in recent years. In self-fluxing systems, two non-centrosymmetric scandium borates with classical B5O10 groups, namely Rb7SrSc2B15O30 (I) and Rb7CaSc2B15O30 (II), were successfully discovered. Both I and II exhibit a short ultraviolet (UV) cutoff edge (<200 nm) and appropriate second-harmonic generation efficiency (∼0.76 × KH2PO4, ∼0.88 × KH2PO4 at 1064 nm, respectively). According to theoretical calculations, it is speculated that the band gap and NLO characteristics of these two compounds are mostly derived from the B5O10 group and the ScO6 octahedron. Due to the short cutoff edges of I and II, they may be considered as potential NLO materials in the UV and even deep UV spectral ranges. Furthermore, the advent of I and II adds to the diversity of rare earth borates.
研究领域:
无机化学
·
材料科学
·
固体化学
·
非线性光学
·
晶体工程
·
紫外光功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2024
·Vol. 110
·期 2
·333-345
·
IF 2.3
Peng Jia,Wu Hongdan,Zhou Zhihui,Li Rongxue
Boron-doped silica membrane (B-SiO 2 membrane) was prepared using the sol-gel method, with 1, 2-bis(triethoxysiliconyl) ethane (BTESE) and boric acid as raw materials and ethanol as the solvent. The effects of the B/BTESE molar composition and feed liquid temperature on the structure and dewatering properties of the B-SiO 2 membranes were investigated. The results show that boron is successfully doped into the SiO 2 skeleton, Si-C-C-Si bond condensation forms lots of hydrothermal stable Si-O-B bonds and Si-O-Si bonds, resulting in an increase in surface hydrophilicity, a decrease in pore size and an improvement in pervaporation and dehydration performance. The B-SiO 2 membrane was subjected to HCl post-treatment to evaluate its long-term stability. Following boron acid modification and HCl post-treatment, all the SiO 2 membranes exhibited microporous characteristics with a decrease in the specific surface area and pore size. Although membranes’ thickness showed minimal variation, the pervaporation dehydration performance was substantially enhanced. After a 216 h long-term stability test, the membranes exhibited excellent performance, with a stable flux of 2.61 kg·m −2 ·h −1 and a separation factor above 552. Graphical
研究领域:
膜科学
·
化学工程
·
材料科学
·
分离技术
✓ 已验证
DOI
高影响因子
IONICS
·
2024
·Vol. 30
·期 4
·2259-2271
·
IF 2.4
He Qihang,Wang Lei,Xiao Feng,Su Rong,Chen Lichuan,Jiang Yu,Jia Bin,He Ping,Zeng Yali,Zhou Yun,Wan Ying,Tang Bin
Graphene oxide (GO) exhibits unique layered structures and excellent electrical conductivity, and the multiple surface termination groups are favorable for hosting impressive performance for electrochemical reactions. Therefore, a two-dimensional layered GO-based catalyst may become a novel high-efficiency electrocatalyst to replace traditional noble metal electrocatalysts. Herein, Co–Mo–B/GO (CMBG) nanocomposites are successfully prepared by electroless deposition for the oxygen evolution reaction (OER). GO constructs multi-layer three-dimensional structure with large surface area, which helps to increase electron transfer and mass transfer within the materials. Due to the introduction of Mo, the aggregation of nanoparticles on GO is reduced, and also the synergistic effect among Co, Mo, and B improves the electrocatalytic performance of as-prepared materials. Moreover, electrochemical tests reveal that the CMBG electrocatalyst can reduce the charge transfer resistance toward the OER and increase electrochemical active sites, leading to enhancing the OER performance. When the molar ratio of Mo/(Co + Mo) is 3:100, overpotential of CMBG is only 270 mV at 10 mA cm −2 . In addition, CMBG shows long-term electrocatalytic stability even after 24-h test. This work provides a feasible way for the preparation of ternary boride electrocatalyst for OER.
研究领域:
材料科学
·
电化学
·
纳米技术
·
能量转换
·
催化
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2013
·
IF 3.535
Kelei Zhuo,Yujing Wei,Jingjing Ma,Yujuan Chen,Guangyue Bai
Several alkylmethylimidazolium tetraphenylborates (C n mim-TPB, n = 2–10) were synthesized and explored as ion exchangers in plasticized PVC membranes with very attractive sensing behaviors. And then a series of ion-selective electrodes (ISEs) were prepared and their potentiometric properties were investigated. The proposed electrodes exhibited Nernstian responses to alkylmethylimidazolium-based ionic liquid cations [C n mim] + . These electrodes were successfully applied in the determination of thermodynamic parameters of ionic liquids in aqueous solutions and in the detection of [C n mim] + in tap water and distilled water with satisfactory results. For the as-prepared ISEs, one special and important relationship was observed between the selectivity coefficients and the length of alkyl side chains of interfering cations [C n mim] + . The proper understanding of this relationship should facilitate the development of new method for the determination of ionic liquids using ISEs.
研究领域:
分析化学
·
电化学
·
环境监测
·
离子传感
·
药物分析
·
水处理
·
生物传感器
·
物理化学
✓ 已验证
DOI
高影响因子
SURFACE REVIEW AND LETTERS
·
2021
·
IF 1.152
HAOTIAN CHI,JUNYING ZHANG,HENG YUAN,ZHONGYU CAI,SHENG ZOU,WEI QUAN
The most sensitive spin-exchange relaxation-free (SERF) magnetometer generally requires a working temperature greater than 100 ∘ C. To date, octadecyltrichlorosilane (OTS) coating is one of the best candidates for this temperature range. However, the performance and consistency of the OTS coatings within the alkali-metal vapor cells are still poor. In this paper, the formation of OTS coatings on borosilicate glass (BG) substrates was investigated. The effects of ambient relative humidity (RH) on the formation of OTS coatings were examined by atomic force microscopy (AFM) and contact angle measurement. The results showed that 75 % RH can improve the order of the OTS coatings and reduce the root mean square (RMS) roughness of the OTS coatings. Under three different ambient RHs, the soaking time of OTS molecules should be greater than 60 min to form complete OTS coating.
研究领域:
材料科学
·
应用物理
·
表面化学
·
纳米技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）