Small
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2024
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IF 13
Xue Ou,Xinrui Chen,Siyu Zhao,Yarong Shi,Junhua Zhang,Min Wu,Arthur J. Ragauskas,Xueping Song,Zhanying Zhang
Carbon dots (CDs) have a wide light absorption range, which are promising candidates for photocatalytic water splitting H 2 evolution, but they show low activity for hydrogen evolution reaction (HER) due to the slow transfer efficiencies of photogenerated carriers. The electron cloud density of photocatalyst is essential for the separation and migration of photogenerated carriers. In this study, the effect mechanism of electron cloud density regulated by the substituents with different electronic effects on the photocatalytic HER of glucose-based CDs is clarified. CDs-SO 3 H and CDs-OH are first obtained by introducing electron-drawing group (─SO 3 H) and electron-donating group (─OH) using a tailoring post-processing strategy. Experimental results show that the H 2 yield catalyzed by CDs-SO 3 H is 89.95 µmol•g −1 in 4 h, which is about four times that of CDs, and 7.4 times that of CDs-OH. The ─SO 3 H induces a much negative energy band and high electron cloud density on CDs edges, promoting the separation and transfer of photogenerated carriers; while the CDs-OH exhibits a high positive charge density and an upward energy band, hindering the surface complexation of electron-hole pairs and HER. This study will provide an insight into the design of CDs catalysts with efficient photocatalytic HER at a molecular level.
研究领域:
材料科学
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光催化
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产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
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2025
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IF 9.5
Zhenxing Li,Hong Tu,Taihong Zhang,Jinhong Hu,Xiang Zhou,Li-Wei Liu,Jian Wu,Song Yang
The utilization of semiconductor graphitic carbon nitride (gCN) for organic pollutant degradation represents an eco-friendly remediation. Presently, the focus of modification strategies for gCN primarily revolves around element doping, heterojunction, and morphology, with little attention given to embellishing its intrinsic framework. Herein, a novel gCN-based privileged photocatalyst was established through controllable nitrogen-hydrogen bond addition/elimination and acylation reactions. Compared to pristine gCN, structurally decorated gCN-A exhibits a larger specific surface area, enhanced fluorescence lifetime, extended visible light response range, and narrow bandgap, which is beneficial to accelerating photon-generated carrier separation and facilitating stable electron migration. Meanwhile, gCN-A demonstrates moderate to strong degradation performance against 5 different organic pollutants, particularly Rhodamine B (98.54%/6 min) and Tetracycline (87.86%/10 min). •O2– was validated as the principal reactive species in organic contamination removal by electron spin resonance and scavenger experiments. Encouragingly, among the three antibacterial bioassays, gCN-A displays the best inhibitory performance against Pseudomonas syringae pv actinidiae (100%), while also degrading the corresponding antimicrobial. Theoretical calculations revealed that modifying the nitrogen-hydrogen bonds in gCN alters electron cloud density distribution and promotes electron-hole separation. Overall, current study provides a promising perspective on constructing multifunctional photocatalysts for degrading contaminants and inactivating pathogens through covalent modification.
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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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2024
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IF 8.3
Xiaoying Zhao,Ruoyan Miao,Tianze Xu,Xiaolong Du,Xueyan Zhang,Wanyu Zhao,Huidong Xie,Liang Zhang,Jianzheng He,Zhenhui Ma,Hu Liu
Changeable substituent groups of organic molecules can provide an opportunity to clarify the antibacterial mechanism of organic molecules by tuning the electron cloud density of their skeleton. However, understanding the antibacterial mechanism of organic molecules is challenging. Herein, we reported a molecular view strategy for clarifying the antibacterial switch mechanism by tuning electron cloud density of cinnamaldehyde molecule skeleton. The cinnamaldehyde and its derivatives were self-assembled into nanosheets with excellent water solubility, respectively. The experimental results show that α-bromocinnamaldehyde (BCA) nanosheets exhibits unprecedented antibacterial activity, but there is no antibacterial activity for α-methylcinnamaldehyde nanosheets. Therefore, the BCA nanosheets and α-methylcinnamaldehyde nanosheets achieve an antibacterial switch. Theoretical calculations further confirmed that the electron-withdrawing substituent of the bromine atom leads to a lower electron cloud density of the aldehyde group than that of the electron-donor substituent of the methyl group at the α-position of the cinnamaldehyde skeleton, which is a key point in elucidating the antimicrobial switch mechanism. The excellent biocompatibility of BCA nanosheets was confirmed by CCK-8. The mouse wound infection model, H&E staining, and the crawling ability of drosophila larvae show that as-prepared BCA nanosheets are safe and promising for wound healing. This study provides a new strategy for the synthesis of low-cost organic nanomaterials with good biocompatibility. It is expected to expand the application of natural organic small molecule materials in antimicrobial agents.
研究领域:
有机化学
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纳米技术
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生物医学工程
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材料科学
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药学
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产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2025
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IF 19
Dongxu Shen,Yarong Liu,Chongchong Chen,Zhirong Yang,Hao Li,Shanghao Xiao,Wenjia Wu,Jingtao Wang
Precise construction of proton transfer pathways and modulation of proton carrier microenvironments are crucial for achieving high proton conduction in proton exchange membranes (PEMs). Despite extensive efforts to tailor these microenvironments, the underlying regulation of electron cloud density around proton carriers, intrinsically linked to proton conduction, remains largely overlooked. Herein, MIL-53-SO 3 H-X (X = –F, –Br, –H, –CH 3 ) nanosheets are synthesized via solvothermal coordination of Cr 3+ ions with functionalized terephthalic acid (BDC-X) ligands, followed by post-synthetic sulfonation at unsaturated Cr 3+ sites to anchor –SO 3 H groups. Density functional theory (DFT) calculations and experimental results reveal that electron-withdrawing –F groups enhance the electron cloud density around –SO 3 H sites, shortening transfer distance, aligning water molecules, and lowering the proton transfer barrier. Conversely, electron-donating –CH 3 groups deplete the electron cloud density in the –SO 3 H region, disrupting proton transport pathways. The MIL-53-SO 3 H-F nanosheet achieves an intrinsic proton conductivity of 298.3 mS cm −1 at 80 °C and 98% RH, a 4.5-fold increase over MIL-53-SO 3 H-CH 3 nanosheets (65.5 mS cm −1 ), as measured by the comb electrode. The corresponding lamellar membrane delivers a high peak power density of 734.8 mW cm −2 and remains stable for over 100 h in H 2 /O 2 PEM fuel cells (PEMFCs).
研究领域:
材料科学
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电化学
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能源材料
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纳米材料
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膜科学
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燃料电池
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产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2025
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IF 19
Xu Jia,Jiyang Tian,Qian Zhang,Jiajun Wan,Hongjiang Song,Ying Xie,Jie Liu
For I 2 cathodes, the severe polyiodide shuttling and sluggish reaction kinetics result in unsatisfactory cycling lifespan and rate performance. Herein, a bifunctional electrophilic host is designed by engineering the electron cloud density to effectively anchor electron-rich polyiodides. Three configurations are initially screened through density functional theory simulations, which reveal that Si─O bonds can firmly anchor I 3 − via Si electrophilic centers. Owing to the considerably lower electronegativity of Si (1.90) than that of O (3.44), electrons surrounding Si atoms are strongly drawn toward O atoms, creating Si electrophilic centers. Specifically, I 3 − adsorbed onto Si─O bonds exhibits a favorable orbital configuration with a low energy gap, thereby kinetically enhancing polyiodide conversion. As a proof of concept, SiO 2 nanocrystals embedded in conductive microporous bio-carbon are derived from poplar flowers. The resulting I 2 cathodes demonstrate excellent cycling stability over 110 000 cycles at 4 A g −1 and a high rate performance with a capacity of 123.8 mAh g −1 at 100 C. Furthermore, the I 2 cathode with a loading as high as 36.5 mg cm −2 can also perform well in terms of 127.6 mAh g −1 after 100 cycles. This study presents a new route for the rational design of high-efficiency and sustainable hosts for I 2 cathodes.
研究领域:
储能
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材料科学
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电化学
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纳米技术
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计算化学
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产品关联
DOI
高影响因子
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