DIAMOND AND RELATED MATERIALS
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2025
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IF 5.1
Long Wen,Jiangtao Huang,Jiaoning Tang,Peigang Han,Zongyan Zhang,Junrong Zeng,Jingwen Nan,Jinghong Yu,Chi Fang,Zihao Cheng,Jiaming Liang,Yang He,Liyu Lin,Bin He
The electrocatalytic nitrate (NO 3 − ) reduction to ammonia (NH 3 ) offers a solution for simultaneous environmental remediation and sustainable ammonia production. However, the rational design of nanocrystalline diamond (NCD) film electrodes balancing high activity and long-term stability remains a critical challenge. Herein, the defect chemistry and surface architecture of NCD films were tailored by adjusting the H 2 /Ar gas ratio in a mixed atmosphere of N 2 , CH 4 , Ar, and H 2 using hot-filament chemical vapor deposition (HFCVD). A series of NCD films with sp 3 /sp 2 ratios of 0.71, 1.14, 1.83, 3.12, and 6.14 were prepared by varying the H 2 /Ar gas ratio, corresponding to electrical conductivities of 18, 8.62, 7.94, 6.1, and 4.18 S/m, respectively. The sp 2 carbon phase serves as the primary active site for nitrate adsorption and electron transfer via its conjugated π-bond network. In addition, the sp 3 carbon phase provides structural stability through its robust tetrahedral framework. The electrode with the sp 3 /sp 2 ratio of 0.71 (H0) achieved the highest faradaic efficiency (FE) of 75.0 % for ammonia synthesis at −1.5 V (vs. RHE), whereas the electrode with the sp 3 /sp 2 ratio of 1.14 (H5) exhibited a slightly lower FE of 65.2 % but superior long-term stability, maintaining a steady faradaic efficiency over 50 h of operation. The optimal sp 3 /sp 2 ratio window (0.7–1.1) balances electron transport efficiency (sp 2 -dominated) and structural durability (sp 3 -dominated), revealing a synergistic interplay between defect-mediated conductivity and chemical robustness. Investigation of the mechanism reveals that optimal H 2 /Ar ratios selectively etch sp 2 impurities while preserving conductive pathways, creating a synergistic interplay between defect-mediated electron transport and chemically robust sp 3 frameworks. This study establishes a scalable strategy for engineering high-performance diamond electrocatalysts, bridging the gap between activity and durability in environmental electrochemistry.
研究领域:
材料科学
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环境电化学
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催化
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纳米技术
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表面科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Nano
·
2022
·
IF 13.364
Zhuolei Liu,Sining Yun,Menglong Sun,Jiaoe Dang,Yongwei Zhang,Yinhao Wang,Changwei Dang,Yingying Deng,Dan Qiao
Herein, we designed and constructed MoS 2 @Co 1.11 Te 2 /Co-doped nitrogen carbon dodecahedron with Te nanorods (Co-NCD-T) by rational structure engineering. The as-synthesized MoS 2 @Co 1.11 Te 2 /Co-NCD-T composite served as a bifunctional catalyst for the hydrogen evolution reaction and triiodide reduction reaction. The incorporation of Te nanorods provided additional charge transport channels and subsequently accelerated the electron transport between the electrode and electrolyte. The synergistic effect between Co 1.11 Te 2 and MoS 2 further enhanced the catalytic activity. The MoS 2 @Co 1.11 Te 2 /Co-NCD-T electrode catalyst showed an overpotential of 124 mV when the current density was 10 mA·cm −2 and a small Tafel slope of 49 mV·dec −1 in an alkaline medium. The assembled solar cell exhibited a superior conversion efficiency of 9.00%, significantly higher than Pt (7.32%). The proposed strategy based on rational structure engineering is expected to facilitate the fabrication of hybrids for multi-functional applications.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Synthetic and Systems Biotechnology
·
2025
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IF 4.4
Haizhao Xue,Yinghan Hu,Aabid Manzoor Shah,Xueying Wang,Xiaojia Guo,Yanzhe Huang,Zongbao K. Zhao
The nicotinamide cofactors including nicotinamide adenine dinucleotide (NAD) and its phosphate (NADP) play important roles in facilitating redox reactions for energy metabolism and biosynthesis. To expand the cofactor menu, a non-natural cofactor nicotinamide cytosine dinucleotide (NCD) has been introduced recently. The reduced forms of these cofactors carry reducing equivalents that are essential for cellular metabolism. However, there is a long standing challenge to rationally transfer reducing equivalent from one cofactor to another, albeit such process is highly demanding in metabolic engineering. This study develops a new approach based on malic enzyme (ME)-mediated transhydrogenation to enable reducing equivalents exchange among different cofactors. We used wild-type ME, MaeB and an engineered ME* that favors NAD, NADP and NCD, respectively, to demonstrate such conversions. When an in vitro system initiated with equal amount of NADH and NCD in the presence of ME, ME* and excess amount of pyruvate was held for 2 h, up to 65% NADH was consumed and 57% NCDH was generated. When implemented into NCD self-sufficient Escherichia coli cells, the system directed reducing equivalents toward NCDH-linked formation of lactate. Overall, this work offers an effective strategy to regulate intracellular reducing equivalents that may serve as a novel tool for metabolic engineering and synthetic biology.
研究领域:
生物化学
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分子生物学
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代谢工程
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合成生物学
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微生物学
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DOI
PubMed
高影响因子
Catalysts
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2022
·Vol. 12
·期 11
·1336
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IF 4.501
Anhua Jiang,Xinwen Huang,Geshan Zhang,Wanquan Yang
In recent years, antibiotics (such as levofloxacin (LEV)) have been detected widely in the environment. Semiconductor photocatalysis has been recognized as a promising technology for removing pollutants in the environment. In this work, nitrogen and carbon codoped titanium dioxide nano-catalyst (NCD-TiO2) was immobilized in polyvinyl alcohol (PVA) matrix to form PVA/NCD-TiO2films through solution casting and thermal treatment, which exhibited good photocatalytic efficiency for LEV degradation. The results showed that about 42% LEV can be degraded after 2 h in the presence of PVA/NCD-TiO2nanocomposite film (the weight ratio of NCD-TiO2to PVA is 8% and thermal treatment is 120 °C) under visible light. Moreover, possible pathways of photocatalytic degradation of LEV according to the detected intermediates are proposed, which provide insight into the degradation mechanism of LEV by using PVA/NCD-TiO2photocatalytic films. Finally, the synthesized PVA/NCD-TiO2films exhibited excellent reusability and stability in photocatalysis. This work provides fundamental support for the design of a high-stability, excellent photocatalyst for practical application.Keywords:levofloxacin;polyvinyl alcohol;visible-light photocatalysis;titanium dioxide;water treatment
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
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