ACS Applied Energy Materials
·
2021
·
IF 6.024
Jun Zhang,Shuai Shao,Desen Zhou,Tingmin Di,Tielin Wang
Two-dimensional (2D) layered nanocomposite provides a surface-to-surface heterojunction, which is an effective way to improve the photocatalytic performance because larger contact areas can promote the separation rate of interfacial charge carriers. In this study, Co(OH)2/g-C3N4/Ni(OH)2 2D layered photocatalysts have been successfully synthesized through a simple precipitation–hydrothermal method. The composite achieves a high H2-production rate of 899 μmol·h–1·g–1, which exceeds the rate of samples only coupled with Co(OH)2 and Ni(OH)2 by 4.0 and 1.9 times, respectively. In addition, the activity is even higher than that of the optimized Pt-g-C3N4 sample (1 wt. % Pt–C). The characterization results reveal the close contact of g-C3N4 and Ni/Co hydroxides, and such a face-to-face contact can greatly improve the interfacial charge-transfer rate, resulting in a high photocatalytic performance. This work demonstrates a simple way to enhance the photocatalytic H2 production of g-C3N4 under the cooperative effect of Co(OH)2 and Ni(OH)2 and provides novel insights into constructing other 2D ternary heterostructure nanocomposites.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-10
·
IF 14.7
Lv Jiabao,Cao Ang,Zhong Yunhao,Lin Qingyang,Li Xiaodong,Wu Hao Bin,Yan Jianhua,Wu Angjian
Renewable-driven electrocatalytic nitrate conversion offers a promising alternative to alleviate nitrate pollution and simultaneously harvest green ammonia. However, due to the complex proton-electron transfer processes, the reaction mechanism remains elusive, thereby limiting energy efficiency. Here, we adopt Ni(OH)₂ as a model catalyst to investigate the dynamic evolution of the reaction interface. A proposed OH cycle mechanism involves the formation of a locally OH-enriched microenvironment to promote the hydrogenation process, which is identified through in-situ spectroscopy and isotopic labelling. By further activating the dynamic state through the implementation of surface vacancies via plasma, we achieve a high Faradaic efficiency of almost 100%. The activated interface accelerates the OH cycle by enhancing dehydroxylation, water dissociation, and OH adsorption, thereby promoting nitrate electroreduction and inhibiting hydrogen evolution. We anticipate that rational activation of the dynamic interfacial state can facilitate electrocatalytic interface activity and improve reaction efficiency.
研究领域:
电化学
·
催化
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION
·
2022
·Vol. 30
·期 1
·230-237
·
IF 2.509
Bin Du,Yuxiang Mai,Nanqing Chen,Yushun Zhao
The interfacial effect of nanoparticles can effectively regulate electron migration in epoxy composites. In this article, hydroxylated C60 [C60(OH)] was prepared and added to epoxy resin (EP). The inhibition of electron motion in epoxy composites was realized, and the dielectric strength of the epoxy composites was improved. The results of dynamic mechanical analysis (DMA) showed that C60(OH) regulated the structure of the crosslinked EP network and increased the crosslink density by 16.5%. The results of a density functional theory (DFT) simulation showed that the doping of C60(OH) formed a potential energy barrier at the C60(OH)-EP interface, which was conducive to the directional migration and capture of electrons driven to C60(OH). Electrostatic force microscopy (EFM) and pulsed electroacoustic (PEA) experiments showed that C60(OH) had a strong ability to capture charge, and the charge migration rate of C60(OH)/EP was 43% lower than that of pure EP in the presence of 10 kV/mm when the EP was doped with 0.1wt% C60(OH). The breakdown strength and volume resistivity increased by 17.87% and 222%, respectively. Thus, this article provides a new method to improve the dielectric strength of epoxy composites.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Materials Research Express
·
2021
·Vol. 8
·期 10
·105002
·
IF 1.62
Wenchang Xi,Pan Jian,Xisong Mao,Deyang Ning,Xuewen Xia,Guohua Liu,Dongyang Shi,Yuanpei Lan
In this work, aiming to evaluate and compare the luminescent property of Eu3+ doped La(OH)3 nanorods and its decomposed compounds of LaOOH and La2O3, La(OH)3: Eu3+ nanorods were synthesized and the decomposition behaviors in air and hydrogen were revealed. Then the luminescent property of 0%–8% Eu3+ doped La(OH)3 nanorods and the 300 °C–800 °C calcined La(OH)3: Eu3+- 4% were studied. Results show that LaOOH is intermediate product during the degradation of La(OH)3 in air or H2, which can be formed at a temperature range in 372.3 °C–592.9 °C in air. Intensity of emission spectra of La(OH)3: Eu3+ nanorods increases with the rising of Eu3+ dopant concentration, and the emission property of Eu3+ doped LaOOH and La2O3 is varied and strengthened with that of La(OH)3: Eu3+. Luminescent matrixes of LaOOH and La2O3 show similar emission spectrum and intensity, and the transitions of the D0 → 7F1 and D0 → 7F2 of Eu3+ each bifurcate into two peaks for both europium (III) doped La2O3 and LaOOH. The revealed results suggest that LaOOH is a relative thermal-stable compound and should be an appropriate matrix as similar as La2O3 for luminescent applications.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Carbon Letters
·
2023
·Vol. 33
·期 5
·1395-1406
·
IF 4.5
Chen Zhangjing,Li Liangliang,Cheng Gang
Photocatalytic CO 2 reduction is a promising approach for reducing CO 2 emissions and achieving the goal of carbon neutrality. In this work, selectively coupling Cu(OH) 2 and CuO with amine-modified brookite TiO 2 (NH 2 –B–TiO 2 ) has been achieved by a simple precipitation method. The results show that CuO is better than Cu(OH) 2 as a co-catalyst to enhance the CO 2 photoreduction capability of NH 2 –B–TiO 2 . The highest rates of CO 2 conversion to CH 4 and CO of NH 2 –B–TiO 2 –CuO composite reach 6.05 and 3.25 μmol h −1 g −1 , respectively, which is higher than 8 times the yield of CH 4 of NH 2 –B–TiO 2 . It is proposed that the NH 2 –B–TiO 2 –CuO composite offers an effective charge transfer through the formation of a p–n junction between NH 2 –B–TiO 2 and CuO interfaces, while in the NH 2 –B–TiO 2 –Cu(OH) 2 composite, the Cu(OH) 2 dominantly serves as an electron sink to capture photo-induced electrons, promoting photo-induced carrier separation. This work provides an ingenious synthetic method for selectively anchoring Cu(OH) 2 and CuO on semiconductors with different charge transfer routes for an efficient CO 2 photoreduction. Graphical abstract
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Qian Wang,Chensheng Lin,Guohong Zou,Mengjiao Liu,Daojiang Gao,Jian Bi,Ling Huang
A new noncentrosymmetric material, namely, K 2 [B 3 O 3 (OH) 5 ] has been obtained by conventional solution reaction. It crystallizes in the orthorhombic space group Ama 2 (no. 40). In the structure of K 2 [B 3 O 3 (OH) 5 ], the BO 2 (OH) triangles and BO 2 (OH) 2 tetrahedra are linked via sharing corners forming the isolated [B 3 O 3 (OH) 5 ] 2- anionic groups with no dangling bonds in oxygen atoms. And K 2 [B 3 O 3 (OH) 5 ] is the first synthetic noncentrosymmetric borates with [B 3 O 3 (OH) 5 ] 2- anionic groups. Powder second-harmonic generation (SHG) using the Kurtz−Perry technique showed that K 2 [B 3 O 3 (OH) 5 ] is type I phase-matchable, and the measured SHG coefficient is 0.32 times that of KH 2 PO 4 . The UV transmittance spectroscopy measurement indicated that the UV absorption edge was below 200 nm, suggesting that K 2 [B 3 O 3 (OH) 5 ] might be a promising deep-UV nonlinear optical material. Band structure and optical property calculations based on DFT methods were also performed.
研究领域:
材料科学
·
晶体学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Yanfei Xin,Xin Dai,Guangjun Lv,Xuedong Wei,Sai Li,Zhiqiang Li,Tong Xue,Ming Shi,Kunyang Zou,Yuanzhen Chen,Yongning Liu
α-Ni(OH)2 is an ideal candidate material for a supercapacitor except for its low conductivity and poor stability. In this work, BO2–-intercalated α-NixCo(1–x)(OH)2 is synthesized by a hydrothermal method at a low cost. The Co dopant can decrease the charge-transfer resistance and enhance the cyclic stability. The special unsaturated electronic state of BO2– enhances the bonding with metal ions and attracts water molecules. Thus, the BO2– ions support the hydroxide layers as pillars and create efficient paths for proton transportation, optimizing the utilization of α-Ni(OH)2. The three-dimensional (3D) flowerlike morphology supplies an enormous number of active sites, and r-GO is added to improve the conductivity. As a result, the modified α-Ni(OH)2 exhibits the specific capacitance of 2179, 1592, and 1423 F·g–1 at 1, 20, and 40 A·g–1, respectively, showing improved rate performance. Matching with the commercial activated carbon (AC) as an anode, the asymmetric capacitor delivers an energy density of 40.66 W·h·kg–1 when its power density is 187.06 W·kg–1. Meanwhile, it retains 81.5% capacitance of the initial cycle at 5 A·g–1 after 3000 cycles. With conductivity enhanced and structure stabilized, the modified α-Ni(OH)2 confronts broader fields of application.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL PAPERS
·
2019
·Vol. 73
·期 7
·1761-1766
·
IF 1.246
Zhang Li-hui,Zhou Yan-biao,Li Wei-li,Zhao Xu-yao,Wang Ya-bo
Lu(OH)CO 3 :Ln 3+ /LuBO 3 :Ln 3+ (Ln = Eu, Tb) nanospheres have been synthesized by the soft chemistry route. This synthesis process does not require the addition of any organic solvents and surfactant. The whole process consists of homogeneous precipitation and hydrothermal process. First, uniform spherical Lu(OH)CO 3 :Ln 3+ (Ln = Eu, Tb) nanoparticles with the sizes of 70 nm were obtained by the classic urea-based homogeneous precipitation. Then, with the above Lu(OH)CO 3 :Ln 3+ (Ln = Eu, Tb) nanosphere as the precursor, the composites of Lu(OH)CO 3 :Ln 3+ /LuBO 3 :Ln 3+ (Ln = Eu, Tb) nanospheres formed by the simple hydrothermal process. The phases, morphologies, as well as the luminescence properties of as-prepared samples were characterized by means of X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, and photoluminescence. Under a short wavelength excitation, the down-conversion Eu 3+ and Tb 3+ -doped LuBO 3 samples were investigated and explained.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2021
·Vol. 46
·期 5
·2189-2197
·
IF 3.591
Yangyang Xin,Dechao Wang,Dongdong Yao,Hailong Ning,Xiaoqian Li,Xiaoqian Ju,Yichi Zhang,Zhiyuan Yang,Yahong Xu,Yaping Zheng
Porous liquids (PLs), a new class of materials with permanent pores and macroscopic flowing behaviors, have attracted much attention for CO2 capture. However, the preparation of PLs is always complicated, which is not suitable for the scale-up. Herein, we propose a rather simple and feasible strategy based on post-synthetic modification of pore generators and the like-dissolves-like principle to synthesize UiO-66-PLs with low-viscosity. To be specific, the metal–organic framework (MOF) UiO-66 with hydroxyl groups (denoted UiO-66-OH) was modified by an organosilane (denoted KH550 or SID) via a post-synthetic modification method, obtaining the pore generator UiO-66-OS (denoted UiO-66-KH550 or UiO-66-SID). Then, the UiO-66-OS was dispersed into two different sterically hindered polydimethylsiloxane solvents (PDMS400 or PDMS6000). Thereby, a series of type 3 PLs (UiO-66-PLs) with superior fluidity at room temperature and accessible porosity were obtained. For instance, the viscosities of UiO-66-KH550-PDMS400 and UiO-66-SID-PDMS400 were 1.1 and 1.5 Pa S at 25 °C, respectively, which were far lower than those of values reported thus far. In addition, gas sorption–desorption measurements indicated that the UiO-66-PLs exhibit superior CO2 sorption performance and great potential for CO2/N2 separation. Moreover, molecular simulation was carried out to verify the retained accessible porosity. Notably, the strategy of constructing type 3 PLs based on the post-synthetic modification of MOFs with organosilane and the like-dissolves-like principle not only provides a new solution for the development of low-viscosity PLs, but also opens a new path for the construction of other types of advanced porous material (APM)-based (e.g., covalent organic frameworks (COFs), porous organic cages (POCs)) PLs, which have potential applications in the fields of gas trapping storage, and catalysis.
研究领域:
材料科学
·
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2019
·
IF 0
Zi-Meng Wang,Yuan-Yuan Cui,Cheng-Xiong Yang,Xiu-Ping Yan
Porous organic nanocages (POCs) have received great concern in diverse areas recently. However, a long reaction time as well as a toxic catalyst or solvents are still used to synthesize POCs, which may limit their broad applications. In addition, the synthesis of modified POCs will largely promote and expand their applications. Here we report a rapid, green, and catalyst-free method to synthesize model nano-POC CC3R and modified CC3S to tune their selectivity and to expand their applications in chiral gas chromatographic (GC) separation of many challengeable chiral alcohols. The nanosized CC3R is successfully synthesized via an ethanolic refluxing method within 4 h without any toxic catalyst or inert gas protection. The prepared CC3R coated capillary column provides good resolution and selectivity to diverse chiral alcohols. The mirrored CC3S and hydroxyl-modified CC3R–OH are also designed and synthesized via the ethanolic refluxing method to tune their selectivity and resolution for chiral alcohols. The introduction of hydroxyl groups into CC3R–OH nanocages largely enhanced their hydrogen-bonding forces to chiral alcohols, leading to the improved resolution and selectivity for chiral alcohols, which revealed the promise of modified POCs in chiral separation. This work may promote the synthesis, modification, and chiral chromatographic application of POCs.
研究领域:
材料科学
·
分析化学
✓ 已验证
DOI
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2021
·Vol. 45
·期 10
·14985-14994
·
IF 5.164
Siqi Qiu,Renbo Guo,Qingyu Wang,Feng Yang,Yibo Han,Xiaoniu Peng,Hui Yuan,Xina Wang
Summary P-type Ni(OH) 2 has been combined with n-type CdS nanorods and nanocrystals for enhanced photocatalytic property due to the p-n junction. Though CdS nanosheets exhibit fast charge transfer and large superficial area, the decoration of Ni(OH) 2 was rarely reported up to now. In this work, the photo-deposition of Ni(OH) 2 nanoparticles on CdS ultrathin nanoflakes was established for efficient photocatalytic H 2 generation. By changing the irradiation time of CdS, the reaction between Ni 2+ and OH − can be controlled for different loading density of Ni(OH) 2 . As the loading density-dependent morphology, light absorption, carrier separation and transfer were systematically studied for the composites, an obvious band gap narrowing from 2.28 to 2.08 eV was revealed, and the carrier separation and transfer between the CdS nanoflakes and Ni(OH) 2 nanoparticles have been enhanced for the composites with deposition time of 3 minutes. These together with the alignment of type “II” bands and the high specific surface area of the flakes and nanoparticles, lead to an optimum H 2 generation of 20.14 mmol/g/h, nearly three times of pure CdS (7.97 mmol/g/h). Such a study not only provides a deposition method of Ni(OH) 2 , but also sheds light on the enhancement strategy for photocatalytic property by controlling the microstructure and aligning the hetero-structured bands.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
Journal of the Australian Ceramic Society
·
2019
·Vol. 56
·期 2
·795-801
·
IF 0.692
Zhang Tao,Wei Yaowu,Chen Junfeng,Li Nan
In spite of the advantages of CaO refractories, such as high refractoriness, potential to produce pure steel molten, and high alkaline corrosion resistance, their application has been limited due to its poor hydration resistance. Introducing additives to improve the hydration resistance of lime is a novel method. The influences of Mg(OH) 2 and sintering temperatures on the sintering and hydration resistance of CaO aggregates that were produced by thermal decomposition were investigated in this paper. The purpose of this work was to produce high-purity CaO raw material with high density, low porosity, well grain growth, and good hydration resistance economically. The sintered samples were characterized by bulk density, apparent porosity, surface appearance, and microstructure. The results indicated that (1) Mg(OH) 2 promoted the grain growth of CaO, reduced the apparent porosity, and improved the density of the specimens. The hydration resistance of the samples was increased. (2) Increasing the sintering temperature improved the hydration resistance of the specimens obviously in the experiment. (3) Grain size of CaO was more uniform with the increment of Mg(OH) 2 content, and the density of the compacts was improved.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）