Nature Catalysis
·
2019
·Vol. 2
·期 12
·1107-1114
·
IF 0
Li Zhe,Fu Jian-Yu,Feng Yi,Dong Cun-Ku,Liu Hui,Du Xi-Wen
Finding highly active and low-cost catalysts is a crucial endeavour to harvest clean hydrogen via electrochemical water splitting. Currently, the best catalyst for the hydrogen evolution reaction is based on metallic platinum whose high price severely restricts large-scale application. Here we report a silver catalyst with superior activity and durability in an acid medium that outperforms commercial platinum on carbon, especially under high applied voltages. We adopt a physical technique—laser ablation in liquid—to generate a high density of stacking faults in silver nanoparticles. We find that the stacking faults can cause a low coordination number and high tensile strain, which jointly improve the adsorption energy and transform the non-active silver into a highly active catalyst. In light of the high activity, conductivity, durability and low price, the silver catalyst can serve as a promising alternative to commercial platinum on carbon for industrial application.
研究领域:
催化
·
电化学
·
材料科学
·
能源材料
✓ 已验证
DOI
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2021
·Vol. 128
·期 1
·1-14
·
IF 2.584
Zhang Dandan,He Yipeng,Wang Rumin,Taub Alan I.
Carbon nanotubes (CNTs) orient in a polymer matrix under electric field due to their highly anisotropic electric polarizability. Under direct current (DC) electric field, CNT also migrates toward electrodes resulting in a non-uniform CNT concentration which can affect the properties gained from CNT alignment. In this study, DC electric field was applied across a CNT/epoxy mixture and the kinetics of CNT migration were studied in real time as a function of electric field strength, CNT concentration and length distribution. The rate constant k of CNT migration was found to be linearly proportional to the electric field strength, while varying the CNT concentration and length distribution exhibited a minimal effect on the migration velocity. Combined with our previous study of the temperature dependence of CNT migration, the relationship between the rate constant k of CNT migration and electric field strength, CNT concentration and length distribution was established. The resulting relationship can be used to manipulate the spatial distribution of CNT to selectively enhance the mechanical, thermal and electrical properties of CNT/polymer composites.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2015
·Vol. 23
·期 6
·5705-5711
·
IF 2.828
Wang Qian,Liu Xiaoyan,Zhang Xinying,Hou Yunyun,Hu Xiaoxin,Liang Xia,Chen Xueping
Tea saponin (TS), a kind of biodegradable surfactant, was chosen to improve the accessible solubilization of pyrene and cadmium (Cd) in co-contaminated soils cultivated Lolium multiflorum . TS obviously improved the accessibility of pyrene and Cd for L. multiflorum to accelerate the process of accumulation and elimination of the pollutants. The chemical forms of Cd was transformed from Fe-Mn oxides and associated to carbonates fractions into exchangeable fractions by adding TS in single Cd and pyrene-Cd contaminated soils. Moreover, the chemical forms of pyrene were transformed from associated fraction into bioaccessible fraction by adding TS in pyrene and pyrene-Cd contaminated soils. In pyrene-Cd contaminated soil, the exchangeable fraction of Cd was hindered in the existence of pyrene, and bioaccessible fraction of pyrene was promoted by the cadmium. Besides, in the process of the pyrene degradation and Cd accumulation, the effect could be improved by the elongation of roots with adding TS, and the microorganism activity was stimulated by TS to accelerate the removal of pollutions. Therefore, Planting L. multiflorum combined with adding TS would be an effective method on the phytoremediation of organics and heavy metals co-contaminated soils.
研究领域:
环境科学
·
植物学
✓ 已验证
DOI
PubMed
高影响因子
Biochar
·
2022
·Vol. 4
·期 1
·1-11
·
IF 11.452
Li Yinxue,Shang Hongru,Cao Yongna,Yang Chunhui,Feng Yujie,Yu Yanling
To remove antibiotics from waste water, an alkali active porous biochar, 850BC, was prepared from corncob xylose residue. In preparation, NaOH dipping was used for silicon removal and KOH activation was operated at 850℃. Further characterization containing BET, SEM, and FTIR were confirmed. 850BC possessed a huge specific surface area of 3043 m 2 ·g −1 , developed pore structure and abundant oxygen functional groups. The adsorption performance of sulfamethoxazole on 850BC was quick and efficient, and the adsorption capacity reached 1429 mg·g −1 , which was significantly higher than other adsorbents reported previously. While pseudo-second-order kinetic model and Langmuir model could better describe the adsorption, chemisorption dominated the SMX adsorption onto 850BC. In virtue of pore-filling and π–π interaction as major mechanism, a large surface area and rich oxygen-containing functional groups led to an excellent adsorption performance. Thus, this preparation method provided a biochar-based adsorbent with enhanced specific surface for efficient removal of antibiotic pollutants. Graphical Abstract
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2017
·Vol. 29
·期 2
·1082-1092
·
IF 2.019
Li Yunming,Yang Wenhu,Ding Shanjun,Fu Xian-Zhu,Sun Rong,Liao Wei-Hsin,Wong Ching-Ping
High energy density polymer-based nanocomposites have shown significant potential in modern electronic devices. However, it is still a great challenge to achieve high dielectric permittivity and low dielectric loss without compromising breakdown strength. Here, we report a facile synthesis of core–shell structured BaTiO 3 @graphene oxide (BT@GO) hybrids as fillers for enhanced energy density of dielectric polymer nanocomposites. The as-fabricated BT@GO/PVDF nanocomposites manifest high dielectric permittivity and low dielectric loss, as well as highly enhanced breakdown strength and maximum energy density. The nanocomposites filled with 20 wt% BT@GO display a dielectric permittivity value of 14 and dielectric loss of 0.04 at 1 kHz with high breakdown strength of 210 MV/m. As a result, the maximum energy density up to 3.88 J/cm 3 , which is about 1.6 and 2.1 times higher than that of BT/PVDF nanocomposites with the same mass fraction and neat PVDF, respectively. These well tuned properties are resulted from the novel structure of BT@GO and synergistic effect of the two constituents, which GO shells as buffer layers could effectively mitigate local electric field concentration for enhanced breakdown strength and BT as cores raised the dielectric permittivity. This work provides a potential design strategy based on graphene oxide interface engineering for developing dielectric polymer nanocomposites with high energy density.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2020
·Vol. 22
·期 3
·1-12
·
IF 2.132
Ma Wenzhong,Li Taiyu,Zhang Qi,Zhong Jing,Matsuyama Hideto
Hydrophilic UiO-66 crystals with superior water adsorption ability were synthesized and incorporated into the polyimide (PI) membrane for efficient aprotic solvent separation via pervaporation. The effect of the different UiO-66 addition in the pyromellitic dianhydride (PMDA)-2, 2-bis[4-(4-amlnophenoxy)phenyl]propane (BAPP)-based PI membrane on the membrane structure, thermal stability, surface hydrophilicity, solvent-resistant, and pervaporation performance was systematically studied. The UiO-66/PI hybrid membranes with small amount content (2 wt%) exhibited high hydrophilicity and excellent swelling resistance due to the superb dispersion benefiting from the excellent complexation of UiO-66 and PI chain. The effects of operational variables such as operating temperature and concentration of feed solution on the pervaporation separation performance of the hybrid membranes with different UiO-66 loadings were investigated. When the mass fraction of UiO-66 was 2 wt%, the hybrid membranes show the permeation flux of 109.7 and 57.1 g/(m 2 h) and separation factor of 34.1 and 133.9, respectively, for DMF/H 2 O and DMAc/H 2 O systems.
Graphical abstract
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
CATALYSIS LETTERS
·
2022
·Vol. 153
·期 7
·2107-2114
·
IF 2.936
Zhao Wenli,Niu Xiaopo,Liu Guangni,Zhang Xiurong,Wang Qingfa
Three kinds of Pt nanocrystals with different morphologies (5 nm cubes, 10 nm cubes and 5 nm truncated octahedrons) were synthesized and employed to fabricate Pt/CNT-USY catalysts for selective ring opening of decalin. The 5 nm truncated octahedral Pt/CNT-USY with exposed (100) and (111) facets exhibited higher yield of ring-opening products (53.9 wt%) than the CNT-USY-supported 5 nm cubic Pt catalyst enclosed by the (100) facets (39.6 wt%). Moreover, the 5 nm cubic Pt showed better catalytic activities compared to the 10 nm cubic Pt/CNT-UST catalyst, which ascribed to the smaller size of Pt NCs enriched more revealable metal active sites. DFT calculations demonstrated that the adsorption of decalin on Pt (111) was stronger than that on Pt (100) facets, which was profitable for the selective ring-opening reaction. Graphical Abstract
研究领域:
催化化学
·
材料科学
·
理论计算化学
✓ 已验证
DOI
高影响因子
MOLECULAR DIVERSITY
·
2018
·Vol. 23
·期 2
·299-306
·
IF 2.229
Lv Xian-Hai,Liu Hao,Ren Zi-Li,Wang Wei,Tang Feng,Cao Hai-Qun
Abstract A series of novel Mannich base derivatives of flavone containing benzylamine moiety was synthesized using the Mannich reaction. The results of antifungal activity are not ideal, but its antifungal effect has a certain increase compared to flavonoids. After that, four bacteria were used to test antibacterial experiments of these compounds; compound 5g (MIC = 0.5, 0.125 mg/L) showed significant inhibitory activity against Staphylococcus aureus and Salmonella gallinarum compared with novobiocin (MIC = 2, 0.25 mg/L). Compound 5s exhibited broad spectrum antibacterial activity (MIC = 1, 0.5, 2, 0.05 mg/L) against four bacteria. The selected compounds 5g and 5s exhibit potent inhibition against Topo II and Topo IV with IC 50 values (0.25–16 mg/L). Molecular docking model showed that the compounds 5g and 5s can bind well to the target by interacting with amino acid residues. It will provide some valuable information for the commercial antibacterial agents. Graphical Abstract
研究领域:
药物化学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-8
·
IF 14.7
Xu Kai,Liu Jin-Cheng,Wang Wei-Wei,Zhou Lu-Lu,Ma Chao,Guan Xuze,Wang Feng Ryan,Li Jun,Jia Chun-Jiang,Yan Chun-Hua
Oxygen vacancy (O v ) is an anionic defect widely existed in metal oxide lattice, as exemplified by CeO 2 , TiO 2 , and ZnO. As O v can modify the band structure of solid, it improves the physicochemical properties such as the semiconducting performance and catalytic behaviours. We report here a new type of O v as an intrinsic part of a perfect crystalline surface. Such non-defect O v stems from the irregular hexagonal sawtooth-shaped structure in the (111) plane of trivalent rare earth oxides (RE 2 O 3 ). The materials with such intrinsic O v structure exhibit excellent performance in ammonia decomposition reaction with surface Ru active sites. Extremely high H 2 formation rate has been achieved at ~1 wt% of Ru loading over Sm 2 O 3 , Y 2 O 3 and Gd 2 O 3 surface, which is 1.5–20 times higher than reported values in the literature. The discovery of intrinsic O v suggests great potentials of applying RE oxides in heterogeneous catalysis and surface chemistry.
研究领域:
催化化学
·
表面科学
✓ 已验证
DOI
高影响因子
Nano Research
·
2024
·Vol. 17
·期 8
·6795-6802
·
IF 9.5
Lu Qi,Yang Jiawei,Zhou Chaofan,Hu Zhaoning,Bu Saiyu,Guo Bingbing,Zhao Yixuan,Liao Junhao,Shang Mingpeng,Chen Ge,Jia Kaicheng,Yin Jianbo,Zeng Qiang,Lin Li,Liu Zhongfan
The transfer of graphene from metallic substrates onto application-specific substrates is usually inevitable for the applications of high-quality graphene films derived from chemical vapour deposition (CVD) approaches. Commonly used to support the graphene films during the transfer, the coating of the polymer would produce the surface contaminations and hinder the industrially compatible transfer. In this work, through the thermal imidization of polyamide acid (PAA) to polyimide (PI) and tuning of the concentration of dangling chains, we achieved the ultraclean and crack-free transfer of graphene wafers with high electronic quality. The resulting contamination-free and hydrophilic surface also enabled the observed improved cell viability in a biomedical applications. By avoiding aqueous etching or the usage of strong bases, our proposed transfer method is industrially compatible for batch transfer of graphene films towards the real applications.
研究领域:
材料科学
·
生物医学工程
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
·
2021
·Vol. 25
·期 10
·2471-2478
·
IF 2.647
Song Qian,Li Hui,Liu Junji,Hu Shi
Cyclic voltammetry (CV) is a powerful and popular electrochemical technique widely used to study the surface structure of materials through the electrochemical behaviors. Herein CV is utilized to study the electrochemical deposition of selenium (Se) on carbon black-supported Pt nanostructures. We synthesized carbon-loaded platinum nanoparticles (Pt/C) by microwave method and studied the electrochemical behavior of selenium on them. Through the experiment of changing the reverse potential, the corresponding relationship between the Se deposition peak and stripping peak was clarified and the deposition and stripping process of Se was proposed. Meanwhile, we synthesized cubic and octahedral nanocrystals of Pt, and used CV to study the Se deposition on these nanosctructures supported by carbon. It was found that the relative intensity of UPD peaks on Pt is different, as Pt cube @C is dominated by (100) and Pt oct @C electrode is dominated by (111) while Pt@C falls in between.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2020
·Vol. 27
·期 4
·1-11
·
IF 2.426
Hou Lei,Wang Zhe,Xu Jingmei,Chen Wenbo,Yang Cancan,Wang Yuanyuan
Mixed matrix membranes (MMMs) were fabricated by incorporating carboxylated multi-walled carbon nanotubes (MWCNTs) into a poly (arylene fluorene ether ketone) that contained amino groups (Am-PAFEK) matrix to improve CO 2 separation performance. The combination of MWCNTs and Am-PAFEK exerted a favorable synergistic effect on the permeability and selectivity of membranes. The extraordinary smooth wall of MWCNTs acts as a highway through which gas passes, providing better permeability. The Am-PAFEK matrix itself has a dense internal structure that provides high gas selectivity. MWCNTs particles evenly distributed among the Am-PAFEK membrane due to the non-covalent bond interaction between the amino and carboxyl group. Efficient CO 2 transport pathways were constructed by homogeneous dispersion of MWCNTs with in MMMs, leading to maintained good selectivity and enhanced permeability. When the amount of carbon nanotubes added was 3 wt.%, that increased by above 60% in comparison to the Am-PAFEK membrane permeability, the CO 2 /CH 4 and CO 2 /N 2 selectivity of the Am-PAFEK/MWCNTs-3% membrane achieved 35.02 and 30.09, respectively. Therefore, the strategy of blending MWCNTs with Am-PAFEK exhibited a promising approach for improving gas permeability.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子