APPLIED CATALYSIS B-ENVIRONMENTAL
·
2017
·
IF 9.446
Shanshan Ding,Danjun Mao,Shaogui Yang,Fei Wang,Lingjun Meng,Mengshu Han,Huan He,Cheng Sun,Bin Xu
The novel boron nitride coupled Bi-rich Bi 4 O 5 Br 2 layered microspheres (h-BN/Bi 4 O 5 Br 2 -LMs) were successfully synthesized via a facile ionic liquid-in-water (IL/W) microemulsion-mediated route. The physical, chemical and optical properties of these heterojunction photocatalysts were thoroughly characterized with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectrometry (EDS), transmission electron microscopy (TEM) and UV–vis diffuse reflection spectroscopy (DRS). Their photocatalytic activities were primarily evaluated by degradation of 4- tert -butylphenol (PTBP), which found 1.0 wt% h-BN/Bi 4 O 5 Br 2 -LMs to be the best one. The photocurrent experiments showed that the photocurrent density of 1.0 wt% h-BN/Bi 4 O 5 Br 2 -LMs was four times higher than that of pure Bi 4 O 5 Br 2 -LMs due to enhanced charge transfer ability of the former. It revealed that the addition of h-BN was in favor of suppressing the photoinduced electron-hole pair recombination of Bi 4 O 5 Br 2 -LMs, so as to improve the photocatalytic activity of the composite. O 2 − and h + were proved to be the main reactive species in the photocatalytic process by scavenger experiments and electron paramagnetic resonance (EPR) spectra. In addition, the photocatalytic mechanism of h-BN/Bi 4 O 5 Br 2 -LMs was further elaborated in this work. The probable degradation products were identified by GC–MS. The proposed conjugated addition and oxidation reactions were described to be the main pathways by combining the frontier electron density calculation and GC–MS results.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2024
·Vol. 18
·期 10
·1-10
·
IF 4.3
Jia Hongwei,Yue Xiaoyang,Hou Yuying,Huang Fei,Cao Cuiyao,Jia Feifei,Liu Guanhua,Zheng Xiaobing,Liu Yunting,Jiang Yanjun
Unspecific peroxygenases exhibit high activity for the selective oxyfunctionalization of inert C(sp 3 )-H bonds using only H 2 O 2 as a clean oxidant, while also exhibiting sensitivity to H 2 O 2 concentration. CdS-based semiconductors are promising for the photosynthesis of H 2 O 2 owing to their adequately negative potential for oxygen reduction reaction via a proton-coupled electron transfer process, however, they suffer from fast H 2 O 2 decomposition on the surface of pristine CdS. Therefore, [Cp*Rh(bpy)H 2 O] 2+ , a highly selective proton-coupled electron transfer catalyst, was anchored onto a supramolecular polymer-grafted CdS nanoflower to construct an efficient integrated photocatalyst for generating H 2 O 2 , mitigating the surface issue of pristine CdS, increasing light absorption, accelerating photonic carrier separation, and enhancing oxygen reduction reaction selectivity to H 2 O 2 . This photocatalyst promoted the light driven H 2 O 2 generation rate up to 1345 µmol·L −1 ·g −1 ·h −1 , which was 2.4 times that of pristine CdS. The constructed heterojunction photocatalyst could supply H 2 O 2 in situ for nonspecific peroxygenases to catalyze the C-H oxyfunctionalization of ethylbenzene, achieving a yield of 81% and an ee value of 99% under optimum conditions. A wide range of substrates were converted to the corresponding chiral alcohols using this photo-enzyme catalytic system, achieving the corresponding chiral alcohols in good yield (51%–88%) and excellent enantioselectivity (90%–99% ee).
研究领域:
生物化学
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材料科学
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催化化学
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DOI
高影响因子
CERAMICS INTERNATIONAL
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2020
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IF 3.83
Yunzi Li,Fei Chen,Xiaoyu Li,Qiang Shen,Lianmeng Zhang
Ceramic/metal composites, as high-temperature structural materials, have limited applications because of their poor machinability . AlN/Mo/Mo 2 B machinable composites were fabricated by adding h-BN to AlN/Mo composites by plasma-activated sintering at various temperatures and at an axial pressure of 30 MPa under argon atmosphere. The sample sintered at 1500 °C exhibited excellent machinability for cemented carbide tools, with a bending strength of approximately 500 MPa and a Vickers hardness value of 9.34 GPa. The effects of sintering temperature on the microstructure, mechanical properties, and machinability were investigated, and the reactions introduced by adding h-BN were studied. These reactions reinforced the composite and newly introduced a Mo 2 B phase, which showed better ability to deflect cracks and prevent them from moving deep inside the composite, thus improving its machinability. This research provides a possible solution for improving the machinability of ceramic/metal composites without sacrificing the strength .
研究领域:
材料科学
·
机械工程
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DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2024
·
IF 6.5
Beibei Chen,Wenquan Dong,Wenchao Shi,Xuanlin Li,Bi Yang,Yang Tong,Lin Zhang,Jianzhang Wang
Developing high-performance of organic solid lubricating coating is of great significance for extending the life of the moving systems/parts. Herein, the non-covalently modified h-BN nanosheets by graphene oxide (BNNSs/GO) were elaborately constructed to enhance the mechanical, friction and wear properties of epoxy nanocomposite coating. The microstructure feature and chemical composition of BNNSs/GO were determined by various spectroscopic techniques. The tribological performance of nanocomposite coatings were tested using ball-on-disc friction tester, and 440C stainless-steel ball with diameter of 8 mm was used as the counterface material. The GO nanosheets acted an active platform for BNNSs, which improved the dispersion of BNNSs and interface interaction with epoxy. The anchoring BNNSs could break the strong π-π, and van der Walls forces among GO nanosheets. The thickness of epoxy nanocomposite coatings was about 60 μm. And the epoxy-1.0 wt%BNNSs/GO demonstrated much higher hardness and elastic modulus than epoxy, increased by 112.62 % and 53.37 %, respectively. The coefficient of friction (COF) and wear rate of epoxy-1.0 wt%BNNSs/GO were the lowest, with a reduction of 89.7 % and 97.5 %, respectively. The synergistic lubricating mechanism of epoxy-BNNSs/GO coating was proposed, which could provide a new light on the design of high antifriction and wear resistance of organic nanocomposite coating.
研究领域:
材料科学
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表面工程
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产品关联
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2024
·
IF 7.7
Lan-Ying Liu,Min-Hua Cui,John Justo Ambuchi,Shi-Ming Niu,Xin-Hui Li,Wo-Long Wang,He Liu,Guo-Shuai Liu,Ai-Jie Wang
Electrocatalytic hydrodechlorination (EHDC) is a promising approach to safely remove halogenated emerging contaminants (HECs) pollutants. However, sluggish production dynamics of adsorbed atomic H (H* ads ) limit the applicability of this green process. In this study, bimetallic Pd–Cu@MXene catalysts were synthesized to achieve highly efficient removal of HECs. The alloy electrode (Pd–Cu@MX/CC) exhibited better EHDC performance in comparison to Pd@MX/CC electrode, resulting in diclofenac degradation efficiency of 93.3 ± 0.1%. The characterization analysis revealed that the Pd 0 /Pd II ratio decreased by forming bimetallic Pd–Cu alloy. Density functional theory calculations further demonstrated the electronic configuration modulation of the Pd–Cu@MXene catalysts, optimizing binging energies for H* and thereby facilitating H* ads production and tuning the reduction capability of H* ads . Noteably, the amounts and reduction potential of H* ads for Pd–Cu@MXene catalysts were 1.5 times higher and 0.37 eV lower than those observed for the mono Pd electrode. Hence, the introduction of Cu into the Pd catalyst optimized the dynamics of H* ads production, thereby conferring significant advantages to EHDC reactions. This augmentation was underscored by the successful application of the alloy catalysts supported by MXene in EHDC experiments involving other HECs, which represented a new paradigm for EHDC for efficient recalcitrant pollutant removal by H* ads .
研究领域:
环境科学
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材料科学
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催化化学
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产品关联
DOI
PubMed
高影响因子
POLYMER SCIENCE SERIES B
·
2015
·Vol. 57
·期 5
·460-472
·
IF 0.577
Sa Zongpeng,Li Yapeng,Zhao Haochen,Hu Qi,Wei Jia,Wang Jingyuan
Through H-shaped macroinitiator glycol-chlorine((Cl) 2 -PEG-(Cl) 2 ) to initiate the ATRP reaction of 2-Hydroxyethyl Methacrylate (HEMA) we synthesized H-shaped copolymer (PHEMA) 2 - b -PEG- b -(PHEMA) 2 . After we modified the copolymer with histidine (His), the self-assembling and drug release behavior was studied. The morphology of the copolymer micelles and drug loaded micelles were examined by transmission electron microscope (TEM). Spherical micelles and core-shell structure with a diameter of 165 nm were obtained (at pH = 7.0). Due to the presence of imidazole-ring in histidine the copolymer show commendable pH-sensitivity, which made the copolymer potential application as drug carrier exhibiting good control-released property.
研究领域:
高分子化学
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药物递送系统
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生物材料
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DOI
高影响因子
Frontiers of Chemical Science and Engineering
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2024
·Vol. 18
·期 11
·1-11
·
IF 4.3
Gao Huimin,Zhang Jinpeng,Zhang Fangyuan,Jing Jieying,Li Wen-Ying
The photocatalytic reduction of CO 2 into formic acid is a feasible approach to alleviate the effects of global climate change and achieve chemical energy storage. It is important to design highly active photocatalysts to improve the selectivity and yield of formic acid. In this study, TiO 2 -based catalysts were prepared and loaded with Pd nanoparticles via an impregnation process. The Pd/H-TiO 2 catalyst demonstrated superior CO 2 reduction activity and a high formic acid production rate of 14.14 mmol cat ·g −1 ·h −1 . The excellent catalytic performance observed in the presence of a Pd/H-TiO 2 catalyst is ascribed to the synergy between O v and Pd. The presence of O v led to increase in CO 2 adsorption while Pd loading enhanced the photogenerated electron-hole pair separation. Electron transfer from H-TiO 2 to Pd also contributed to CO 2 activation.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
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2025
·
IF 3.6
Jingru Zou,Lingmeng Xie,Wen Qin,Xingang Xie,Xing Huo
The Groebke–Blackburn–Bienaymé (GBB) reaction provides efficient access to imidazole-fused heterocycles, yet it is inevitably endowed with an isocyanide-derived secondary amino group in products. Herein, we report a Pd(II)-catalyzed sp2 C–H carbonylative amidation strategy using Co2(CO)8 as a safe CO surrogate. Leveraging the native aryl amino group as a directing motif, this protocol enables direct conversion of GBB adducts into pharmaceutically relevant imidazo[1,2-a]pyridine-fused δ-lactams with up to 86% yield. The method demonstrates exceptional functional group tolerance and eliminates prefunctionalization requirements, offering a streamlined approach to access complex nitrogen-rich architectures.
研究领域:
有机化学
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药物化学
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杂环化学
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转化医学
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分子药理学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Kezhu Xu,Jin Wu,Qunling Fang,Linfeng Bai,Jinyu Duan,Jiaxing Li,Huajian Xu,Ailing Hui,Lingyun Hao,Shouhu Xuan
The organic pollutants and heavy metal ions are critical harmful substances in waste water because they destroy the ecological systems and lead diseases to animals and human beings. Unfortunately, the simultaneously remove of them in one system is still a challenge due to their different treating mechanism. Herein, a novel magnetic h-Fe 3 O 4 @Au/Polydopamine (Au/PDA) hybrid hollow nanosphere which can both absorb the potentially toxic U(VI) ions and catalyze the reduction of the 4-nitrophenol is reported. By using a simple in situ redox-oxidizing polymerization method, the h-Fe 3 O 4 hollow nanosphere is well encapsulated by the Au/PDA hybrid shell to form the dual-functional magnetic hollow nanocomposites. Owing to the hollow interior, uniform and functional PDA coating, and high active Au nanocrystals, the final h-Fe 3 O 4 @Au/PDA hollow nanosphere possesses high potential in nanocatalysis, heavy metal ions adsorption, and drug delivery. Because of the PDA protection, the h-Fe 3 O 4 @Au/PDA nanosphere can even keep 90% activity after 7 cycling catalytic reactions on reduction of 4-nitrophenol. Similarly, the h-Fe 3 O 4 @Au/PDA exhibits a good adsorption effect for U(VI) in nuclear waste and its adsorption capability reaches to 82.9 mg·g −1 by 6 successive adsorption–desorption experiments. Due to the facile magnetic separation, the h-Fe 3 O 4 @Au/PDA nanosphere can be easily collected by applying an external magnetic field. In summary, such a multifunctional recyclable h-Fe 3 O 4 @Au/PDA nanosphere with green and facile synthesis, easy manipulation, efficient adsorption performance and good catalytic activity possesses broad application potential in treatment of coexisting toxic water pollution.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2024
·
IF 5.7
Jinye Huang,Xuan Xuan,Dongmei Xu,Yuezhong Wen
The regulation solutions and mechanisms of reducing pesticide phytotoxicity to nontarget plants are not well-defined and detailed. Here, we have proposed a new detoxification strategy to control the toxic effects of herbicide imazethapyr (IM) induced in wheat seedlings from the perspective of the plasma membrane (PM) H+-ATPase. We found that the changes in PM H+-ATPase activity have a regulatory effect on the phytotoxic effects induced by IM in plants. Treatment with PM H+-ATPase activators restored the reduced auxin content and photosynthetic efficiency caused by IM, thereby promoting plant growth. Application of a PM H+-ATPase inhibitor further reduced phosphorus content and significantly increased 2,4-dihydroxy-7-methoxy-2H,1,4-benzoxazin-3(4H)one (DIMBOA) and jasmonic acid levels. These effects indicate that auxin and DIMBOA may regulate plant growth trends and detoxification effects mediated by PM H+-ATPase. This work opens a new strategy for regulating herbicide toxicity to nontarget plants from the PM H+-ATPase.
研究领域:
植物生理学
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植物生物化学
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农药科学
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产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2020
·
IF 4.825
Ji Wu,Ke Cao,Cai-Yan Zhang,Tao-Tao Xu,Xin-Yu Wen,Bo Li,Junxiao Yang
A palladium catalyzed selective B(3)–H activation/oxidative dehydrogenative coupling for the synthesis of bis(o-carborane)s connected with B(3)–B(3′) and B(3)–B(6′) bonds has been developed for the first time. A plausible mechanism involving stepwise activation of B(3)–H and B(3′/6′)–H bonds by PdII and PdIV was proposed. This work is the first example and the most efficient protocol for synthesis of bis(o-carborane)s connected with B(3)–B(3′) and B(3)–B(6′) bonds, which has important reference for design, synthesis, and application of bis(o-carborane)s in related fields.
研究领域:
有机化学
·
材料科学
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DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2025
·
IF 17.7
Qisong Yi,Lu Lin,Huawei Geng,Shaohua Chen,Yuanchao Shao,Ping He,Zhifeng Liu,Haimei Xu,Tiehong Chen,Yuanshuai Liu,Valentin Valtchev
The hydrothermal stability of zeolites is essential for their potential applications in biomass conversion, especially in processes involving elevated temperatures alongside the use or generation of H 2 O. In this study, we employed F - ions as mineralizers to synthesize hydrothermally stable ZSM-5 zeolites under acidic conditions. The acidic synthesis system promotes zeolites with fewer silanol-terminated lattice defects (ZSM-5(A)) compared to the traditional basic conditions (ZSM-5(B)), endowing materials with substantially higher structural integrity and hydrophobicity. After 10 days of autoclave treatment at 200 °C in aqueous phase, H-ZSM-5(A) demonstrated nearly unchanged reaction rates in the dehydration of cyclohexanol, while H-ZSM-5(B) lost > 50% of the dehydration activity. Additionally, H-ZSM-5(A) delivered higher initial dehydration rates compared to H-ZSM-5(B). The different measured activation energies further revealed variations in reaction pathways during cyclohexanol dehydration, i.e., the monomer- or dimer-mediated routes depending on the concentration of alcohol molecule within zeolite pores, providing additional evidence for the strengthened hydrophobic nature of H-ZSM-5(A). Beyond this, the zeolite surface properties and the strength of cyclohexanol-zeolite interactions may impose additional transport/adsorption barriers attributed to multi-phase phenomena on the more polar H-ZSM-5(B) zeolite surfaces. More importantly, the hydrothermal treatment did not induce significant desilication and dealumination in H-ZSM-5(A), thereby preserving its active acid sites and ensuring exceptional hydrothermal stability. The present work fundamentally studies the synthesis of hydrothermally stable zeolites in an acidic medium using fluorides and expands the understanding of polar interactions in catalysis, characterized by the dehydration of cyclohexanol, for future application in biomass conversion.
研究领域:
催化
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材料科学
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化学工程
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物理化学
·
生物质转化
✓ 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）