ACS ES&T Engineering
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2023
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IF 7.1
Xinying Yang,Wenwen Li,Shibin Wang,Huaijie Shi,Xiaosa Wang,Min Li,Lei Ding,Xing Zhong,Jianguo Wang
Diamond electrodes have been receiving increased attention because of their favorable properties for wastewater treatment. However, the surface properties of the diamond anode have not been fully determined. Herein, an extensive study was conducted to explore hybrid two-dimension nanodiamonds (2D NDs) with variable sp3/sp2 ratios as metal-free electrochemical ozone production (EOP) electrocatalysts. The 2D ND-1100 electrocatalyst with interface heterojunction of sp3/sp2 exhibited outstanding EOP performance compared with the normal ND@G with sp3@sp2 core–shell structure. Theoretical calculations further revealed that a high sp3/sp2 ratio could effectively prohibit the O2*/O3* intermediate dissociation. O3* with five-ring configurations exhibited lower adsorption energies than O2* under the high sp3/sp2 ratio condition, indicating the high O3 selectivity. The optimal sp3/sp2 ratio was predicted to be 4:5 to 8:1 for O3 selective formation. In addition, the 2D ND-1100 electrocatalyst demonstrated remarkable performance in electrodegrading organic pollutants, indicating its broad potential for efficient and advanced oxidation applications. This work provides an effective strategy for the removal of organic pollutants in wastewater based on high-performance hybrid two-dimension nanodiamonds with appropriate sp3/sp2 rations.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
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
危险品化学品经营许可证（带存储）