المؤلفون: Hongxia Wang, Yongcheng Wang, Xin Wen, Jingxiang Zhao, Yue-jie Liu, Shansheng Yu

المصدر: New Journal of Chemistry. 43:5766-5772

مصطلحات موضوعية: Dopant, Band gap, Chemistry, Doping, 02 engineering and technology, General Chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Catalysis, 0104 chemical sciences, Nonmetal, Chemical physics, Monolayer, Materials Chemistry, Molecule, Density functional theory, 0210 nano-technology, Nanosheet

الوصف: Introducing heteroatoms into two-dimensional nanosheets was revealed to be a quite promising strategy to tune their electronic and magnetic properties as well as chemical reactivity, thus greatly widening their application fields. Herein, by means of density functional theory (DFT) computations, we have systematically investigated the electronic and magnetic properties as well as chemical reactivity of MoS2 nanosheets doped with several common nonmetal dopants (B, C, N, O, and P). Our results revealed that these nonmetal atoms can be strongly captured by the S vacancy of the MoS2 nanosheet, ensuring their high stability. Compared with the pristine MoS2 nanosheet, these doped MoS2 systems exhibit decreased band gaps due to the introduction of impurity levels. In particular, the adsorption of gas molecules on the MoS2 monolayer can be enhanced to different degrees after nonmetal doping, suggesting great potential for developing gas sensors or catalysts. Thus, by carefully choosing the nonmetal atoms, the inert basal plane of a MoS2 nanosheet can be effectively activated for various applications.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::c700d98aefabc6b2e64115b085172036Test
https://doi.org/10.1039/c9nj00466aTest

المؤلفون: Kasper Moth-Poulsen, Xin Wen, He Yan, Shanshan Chen, Ruijie Ma, Wenyan Su, Zhenghui Luo, Lintao Hou, Wenliu Zhuang, Qunping Fan, Tao Liu, Yu Li, Donghong Yu, Zhi-Guo Zhang, Zhihong Yin, Xia Guo, Changduk Yang, Ergang Wang, Maojie Zhang

المصدر: Fan, Q, Su, W, Chen, S, Liu, T, Zhuang, W, Ma, R, Wen, X, Yin, Z, Luo, Z, Guo, X, Hou, L, Moth-Poulsen, K, Li, Y, Zhang, Z, Yang, C, Yu, D, Yan, H, Zhang, M & Wang, E 2020, ' A Non-Conjugated Polymer Acceptor for Efficient and Thermally Stable All-Polymer Solar Cells ', Angewandte Chemie-International Edition, vol. 59, no. 45, pp. 19835-19840 . https://doi.org/10.1002/anie.202005662Test
Angewandte Chemie (International Ed. in English)

مصطلحات موضوعية: Materials science, Band gap, Conjugated system, all-polymer solar cells, 010402 general chemistry, Photochemistry, 01 natural sciences, Catalysis, Polymer solar cell, thermal stability, Crystallinity, thioalkyl chain linkages, Thermal stability, HOMO/LUMO, chemistry.chemical_classification, non-conjugated polymer acceptors, 010405 organic chemistry, Communication, General Medicine, General Chemistry, Polymer, Acceptor, Communications, 0104 chemical sciences, power conversion efficiency, chemistry, Solar Energy Materials

الوصف: A non‐conjugated polymer acceptor PF1‐TS4 was firstly synthesized by embedding a thioalkyl segment in the mainchain, which shows excellent photophysical properties on par with a fully conjugated polymer, with a low optical band gap of 1.58 eV and a high absorption coefficient >105 cm−1, a high LUMO level of −3.89 eV, and suitable crystallinity. Matched with the polymer donor PM6, the PF1‐TS4‐based all‐PSC achieved a power conversion efficiency (PCE) of 8.63 %, which is ≈45 % higher than that of a device based on the small molecule acceptor counterpart IDIC16. Moreover, the PF1‐TS4‐based all‐PSC has good thermal stability with ≈70 % of its initial PCE retained after being stored at 85 °C for 180 h, while the IDIC16‐based device only retained ≈50 % of its initial PCE when stored at 85 °C for only 18 h. Our work provides a new strategy to develop efficient polymer acceptor materials by linkage of conjugated units with non‐conjugated thioalkyl segments.
An efficient non‐conjugated polymer acceptor PF1‐TS4 was developed by embedding thioalkyl linkages in the mainchain of a conjugated polymer. The resulting all‐polymer solar cells achieved a promising device efficiency of 8.63 % with excellent thermal stability at 85 °C for 180 hours.

وصف الملف: application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::119b334955d1e7bfb22d3ada119db318Test
https://vbn.aau.dk/ws/files/405083958/anie.202005662.pdfTest

المؤلفون: Xiao-li Ou, Xin Wen, Fan Yang, Shuai Wang, Hong Zhong, Zhanfang Cao, Pei Chen

المصدر: Colloids and Surfaces A: Physicochemical and Engineering Aspects. 549:94-104

مصطلحات موضوعية: 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, Heterogeneous catalysis, 01 natural sciences, 0104 chemical sciences, Catalysis, chemistry.chemical_compound, Colloid and Surface Chemistry, chemistry, Chemical engineering, Triethanolamine, Zeta potential, medicine, Degradation (geology), Surface charge, 0210 nano-technology, Methylene blue, Superparamagnetism, medicine.drug

الوصف: A novel heterogeneous catalyst (TEA/GO@Fe3O4) was synthesized by simple one-step hydrothermal method. Surprisingly, TEA/GO@Fe3O4 showed an extremely fast decomposition rate for methylene blue (MB). According to the characterization results, the superior properties of the TEA/GO@Fe3O4 can be attributed to following factors: (1) the application of GO prevents the agglomeration of Fe3O4 nanoparticles, (2) the delocalized π electrons of GO and the lone pair electrons of triethanolamine and its oxidant products (TEA) promoted the regeneration of Fe2+, (3) the negative surface charge of TEA/GO@Fe3O4 and the coordination between Fe and S can accelerate the diffusion rate of MB toward the surface of catalyst, (4) the prepared materials were superparamagnetic with a negligible coercivity and remanence, (5) the Fe3O4 nanoparticles were immobilized on the surface of GO and functionalized by the TEA. Finally, the presumption mentioned above was proved by TEM, FTIR, XRD, XPS, Zeta potential and the degradation experiments. After the degradation reaction, the catalyst can be quickly separated by external magnetic field. Therefore, the TEA/GO@Fe3O4 is a promising catalyst for the degradation of MB.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::4c3326acdf32f2aba526994fc30d6409Test
https://doi.org/10.1016/j.colsurfa.2018.04.009Test

المؤلفون: Ewa Mijowska, Yanliang Wen, Xiaoguang Liu, Xuecheng Chen, Shuai Zhang, Xin Wen, Xiaoze Shi

المصدر: Scientific Reports
Scientific Reports, Vol 10, Iss 1, Pp 1-12 (2020)

مصطلحات موضوعية: Materials science, Energy storage, chemistry.chemical_element, lcsh:Medicine, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Article, Catalysis, Specific surface area, Porosity, lcsh:Science, Power density, Multidisciplinary, Nanoscale materials, Carbonization, lcsh:R, Natural hazards, 021001 nanoscience & nanotechnology, 0104 chemical sciences, chemistry, Chemical engineering, Sustainability, Yield (chemistry), lcsh:Q, 0210 nano-technology, Carbon, Materials for energy and catalysis

الوصف: Recently great efforts have been focused on converting biowastes into high-valued carbon materials. However, it is still a great challenge to achieve high carbon yield and controllable porous distribution in both industrial and academic research. Inspired by the multi-void structure of waste coffee grounds, herein we fabricated hierarchical porous carbon via the combination of catalytic carbonization and alkali activation. The catalytic carbonization process was applied to obtain well-defined mesoporous carbon with carbon yield as high as 42.5 wt%, and subsequent alkali activation process produced hierarchical porous carbon with ultrahigh specific surface area (3549 m2g−1) and large meso-/macropores volume (1.64 cm3g−1). In three-electrode system, the electrode exhibited a high capacitance of 440 F g−1at 0.5 A g−1in 6 M KOH aqueous electrolyte, superior to that of many reported biomass-derived porous carbons. In two-electrode system, its energy density reached to 101 Wh kg−1at the power density of 900 W kg−1in 1-Ethyl-3-Methylimidazolium Tetrafluoroborate (EMIMBF4). This work provided a cost-effective strategy to recycle biowastes into hierarchical porous carbon with high yield for high-performance energy storage application.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::90165af8fde353922bad5df77130015aTest
https://pubmed.ncbi.nlm.nih.gov/32103118Test

المؤلفون: Qing-Yun Hu, Xin-Wen Zhou, Chen Di, Lai-Ming Luo, Rong-Hua Zhang

المصدر: ACS Applied Energy Materials. 1:2619-2629

مصطلحات موضوعية: Materials science, Energy Engineering and Power Technology, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, Epitaxy, Electrochemistry, 01 natural sciences, Redox, Nanomaterial-based catalyst, 0104 chemical sciences, Catalysis, Sodium borohydride, chemistry.chemical_compound, chemistry, Chemical engineering, Materials Chemistry, Chemical Engineering (miscellaneous), Methanol, Electrical and Electronic Engineering, 0210 nano-technology, Seed crystal

الوصف: Trimetallic CoAuPd nanocatalysts are synthesized by a classical successive reduction method using P123 as protectant and sodium borohydride as reductant. The structure, composition, and morphology of the nanocatalysts are measured and characterized through different techniques. The obtained results show that the trimetallic CoAuPd nanocatalysts have two kinds of super three-dimensional (3D) structures: the novel nanothornbush and nanocluster structure. The formation of these epitaxial multilevel structures may be attributed to the Co seed crystal ferromagnetism and multilevel self-assembly. The electrocatalytic properties of the CoAuPd nanocatalysts are investigated deeply. Furthermore, the electrochemical dealloying method is also adopted to enhance the electrocatalytic performance. The results of dealloying gradient tests for the methanol oxidation reaction (MOR) demonstrate that the reaction active sites, electrochemical specific active areas, and catalytic activity of the CoAuPd nanocatalysts graduall...

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::b17237bc5eb43659f9f0e7b19f755c24Test
https://doi.org/10.1021/acsaem.8b00329Test

المؤلفون: Jianjun Wang, Aidong Tang, Xin Wen, Peng Yan, Lin Tan, Jing Chen, Laifu Zhong

المصدر: Journal of Alloys and Compounds. 743:394-402

مصطلحات موضوعية: Materials science, chemistry.chemical_element, Nanoparticle, 02 engineering and technology, Tartrate, 010402 general chemistry, 01 natural sciences, law.invention, Catalysis, chemistry.chemical_compound, Antimony, law, Materials Chemistry, medicine, Calcination, Nanocomposite, Carbonization, Mechanical Engineering, Metals and Alloys, Palygorskite, 021001 nanoscience & nanotechnology, 0104 chemical sciences, chemistry, Chemical engineering, Mechanics of Materials, 0210 nano-technology, medicine.drug

الوصف: A series of Sb/C/palygorskite nanocomposites, Sb (2–3 nm) nanoparticles anchored inside a porous palygorskite, were successfully prepared through facile impregnation and in-situ calcination method. Catalytic performance was evaluated on the basis of the reduction reaction of 4-nitrophenol where NaBH4 was used as reductant. In the synthesis process, the reduction of SbO+ and carbonization of tartrate ions occurred simultaneously, thereby inhibiting the agglomeration of Sb particles and promoting the dispersion of 2–3 nm Sb nanoparticles on the surface and tunnel of the palygroskite. The produced nanocomposites, x%-Sb/C/palygorskite composites, exhibited higher turnover frequency and stability than Sb/C nanocomposites synthesized under the same condition but without palygroskite as support, which is attributed to a strong interactions between Sb nanoparticles and modified palygorskite. These interactions efficiently stabilize the Sb nanoparticles and enhance the catalytic activity and stability. What's more, the presence status of antimony in the nanocomposite is clearly explained. This research can provide a new strategy for designing functional nanocomposites that are based on natural clay mineral.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::6b9ca5a31ad80c3b93f2cbcfe0518887Test
https://doi.org/10.1016/j.jallcom.2018.01.338Test

المؤلفون: Yong Wang, Xin Cui, Xin Wen, X. Peter Zhang

المصدر: Journal of the American Chemical Society. 140:4792-4796

مصطلحات موضوعية: Pyrrolidines, Alkylation, Free Radicals, 010402 general chemistry, Ring (chemistry), 01 natural sciences, Biochemistry, Radical cyclization, Article, Catalysis, chemistry.chemical_compound, Colloid and Surface Chemistry, Organometallic Compounds, Molecule, Molecular Structure, 010405 organic chemistry, Enantioselective synthesis, Stereoisomerism, Cobalt, General Chemistry, Bond formation, Combinatorial chemistry, 0104 chemical sciences, chemistry, Cyclization, Diazo

الوصف: Radical cyclization represents a powerful strategy for construction of ring structures. Traditional radical cyclization, which is based on radical addition as the key step, necessitates the use of unsaturated substrates. Guided by the concept of metalloradical catalysis, a different mode of radical cyclization that can employ saturated C—H substrates is demonstrated through the development of a Co(II)-based system for catalytic activation of aliphatic diazo compounds for enantioselective radical alkylation of various C(sp(3))—H bonds. It allows for efficient construction of chiral pyrrolidines and other valuable 5-membered cyclic compounds. This alternative strategy of radical cyclization provides a new retrosynthetic paradigm to prepare five-membered cyclic molecules from readily available open-chain aldehydes through the union of C—H and C═O elements for C—C bond formation.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4058be4b26a4bcce311298c2a5ded668Test
https://doi.org/10.1021/jacs.8b01662Test

المؤلفون: Dai Zhongxu, Qing-Yun Hu, Lai-Ming Luo, Rong-Hua Zhang, Xin-Wen Zhou, Shao-Na Chen, Chang-Ying Yang, Chen Di

المصدر: Journal of Electroanalytical Chemistry. 812:90-95

مصطلحات موضوعية: General Chemical Engineering, Alloy, 02 engineering and technology, engineering.material, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Nanomaterial-based catalyst, 0104 chemical sciences, Analytical Chemistry, Catalysis, chemistry.chemical_compound, X-ray photoelectron spectroscopy, chemistry, Chemical engineering, Transmission electron microscopy, Electrochemistry, engineering, Methanol, Particle size, 0210 nano-technology, High-resolution transmission electron microscopy

الوصف: Highly monodispersed hollow PtPdAu nanoalloys (HNAs) are synthesized through two-step successive reduction (PtPdAu HNAs-1) and one-pot co-reduction method (PtPdAu HNAs-2) using PEO19-PPO69-PEO19 (P123) as both reductant and stabilizer. Subsequent X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and HRTEM revealed that both two kinds catalysts have a hollow alloy structure and the average particle size reached 10.4 and 9.6 nm, respectively. This work demonstrates that the addition of Au can effectively improve the electrocatalytic performance of Pt-based catalysts. By compared with PtPdAu HNAs-1 and commercial Pt/C, PtPdAu HNAs-2 exhibited superior performance toward methanol oxidation reaction (MOR), including a more negative onset potential of ~0.2 V, higher mass peak current density of 263.5 mA mgPt−1 and lone-term durability.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::1a06788439107c79c25d19125d775073Test
https://doi.org/10.1016/j.jelechem.2018.01.051Test

المؤلفون: X. Peter Zhang, Xin Wen, Yong Wang

المصدر: Chemical Science. 9:5082-5086

مصطلحات موضوعية: 010405 organic chemistry, Chemistry, Stereochemistry, Enantioselective synthesis, Regioselectivity, General Chemistry, Bond formation, Alkylation, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, Catalysis, Intramolecular force, Stereoselectivity, Chemoselectivity

الوصف: A new C-C bond formation strategy based on enantioselective radical alkylation of C(sp3)-H bonds via Co(ii)-based metalloradical catalysis has been demonstrated for stereoselective synthesis of chiral indolines. The Co(ii)-based system enables activation of aryldiazomethanes as radical precursors at room temperature for enantioselective intramolecular radical alkylation of broad types of C-H bonds, constructing 2-substituted indolines in high yields with excellent enantioselectivities. In addition to chemoselectivity and regioselectivity, this Co(ii)-catalyzed alkylation features tolerance to functional groups and compatibility with heteroaryl substrates. Detailed mechanistic studies provide insight into the underlying stepwise radical pathway.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::daf96002e87868b590fbf22d6d86ff63Test
https://doi.org/10.1039/c8sc01476kTest

المؤلفون: Fenghong Li, Yang Miao, Yue Wang, Xin Wen, Junjun Su, Weiping Chen

المصدر: New Journal of Chemistry. 42:5005-5013

مصطلحات موضوعية: Photocurrent, Fullerene, Energy conversion efficiency, 02 engineering and technology, General Chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, Photochemistry, 01 natural sciences, Catalysis, Polymer solar cell, 0104 chemical sciences, chemistry.chemical_compound, Suzuki reaction, chemistry, Quinacridone, Materials Chemistry, Knoevenagel condensation, 0210 nano-technology, HOMO/LUMO

الوصف: A new class of benzothiadiazole-oligo(3-hexylthiophene) flanked dicyanomethylenated quinacridone derivatives DCNQA-BT-Tn (n = 1–3) has been designed and synthesized in good yield by iterative bromination and Suzuki coupling reactions, followed by Knoevenagel condensation. The photophysical and electrochemical properties of the compounds have been fully investigated. They showed intense and broad absorption at the visible and near-infrared regions, a suitable LUMO energy level at about −3.7 eV, and the appropriate film-formation properties. The bulk heterojunction (BHJ) photovoltaic devices based on the blend film of P3HT/DCNQA-BT-T1 (P3HT = poly(3-hexylthiophene)) showed a power conversion efficiency (PCE) of 0.73% under AM 1.5, 100 mW cm−2 irradiation. Compared with the traditional P3HT/PC61BM (PC61BM = [6,6]-phenyl-C61-butyric acid methyl ester) device, the P3HT/DCNQA-BT-T1 device displayed intense absorption in the near-infrared region (650–750 nm) and effectively contributed to the photocurrent. These results indicate that DCNQA derivatives are promising non-fullerenes acceptors for the BHJ polymer solar cells.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::560744ca46c7c13e4e304bf9c2a51e46Test
https://doi.org/10.1039/c8nj00102bTest