|
|
Na+掺杂g-C3N4通过NaHCO3辅助策略用于高效光催化产H2O2
|
Abstract:
光催化制备过氧化氢(H2O2)因其绿色、可持续的特点，被认为是替代传统蒽醌法的重要途径之一。针对石墨相氮化碳(g-C3N4)存在比表面积有限、光生载流子复合严重及氧还原活性不足等问题，本研究采用碳酸氢钠(NaHCO3)作为改性剂，通过一步高温热缩聚法制备Na+掺杂改性g-C3N4(CN-Na)光催化材料。结果表明，NaHCO3的引入在材料形成过程中起到结构调控作用，使块体g-C3N4发生部分剥离与破碎，比表面积显著提升，同时晶体结构发生轻微膨胀，证明Na+成功掺入骨架结构。紫外-可见漫反射光谱显示，CN-Na的吸收边发生红移，禁带宽度减小，可见光响应能力增强。光电化学测试表明，CN-Na具有更高的瞬态光电流响应和更低的电荷转移阻抗，说明其光生电子–空穴分离与迁移效率得到显著改善。在可见光照射下，CN-Na表现出优异的H2O2生成性能，其产率达到未改性样品的10倍以上，并随反应时间稳定增长。电子顺磁共振(EPR)结果进一步表明，Na改性促进了超氧自由基(
)的生成，从而增强了两电子氧还原路径的反应效率。综上，NaHCO3辅助的Na+掺杂策略能够实现g-C3N4结构与电子性质的协同优化，显著提升其光催化H2O2生成性能，为高效太阳能驱动绿色过氧化氢合成提供了有效思路。
Photocatalytic production of hydrogen peroxide (H2O2) is considered a green and sustainable alternative to the conventional anthraquinone process. However, graphitic carbon nitride (g-C3N4) suffers from limited specific surface area, severe photogenerated charge carrier recombination, and insufficient oxygen reduction activity, which restrict its practical photocatalytic performance. In this work, sodium bicarbonate (NaHCO3) was employed as a modifying agent to construct Na+-doped g-C3N4 (CN-Na) via a one-step high-temperature thermal polycondensation method. The results indicate that the introduction of NaHCO3 plays a crucial role in regulating the material structure, leading to partial exfoliation and fragmentation of bulk g-C3N4, thereby significantly increasing the specific surface area. Meanwhile, a slight lattice expansion confirms the successful incorporation of Na+ into the g-C3N4 framework. UV-vis diffuse reflectance spectroscopy reveals a red shift of the absorption edge and a narrowed band gap, indicating enhanced visible-light harvesting ability. Photoelectrochemical measurements show that CN-Na exhibits a higher transient photocurrent response and lower charge transfer resistance, demonstrating improved separation and migration efficiency of photogenerated electron–hole pairs. Under visible-light
| [1] | Sayed, M., Li, H. and Bie, C. (2025) Challenges and Prospects of Photocatalytic H2O2 Production. Acta Physico-Chimica Sinica, 41, Article 100117. https://doi.org/10.1016/j.actphy.2025.100117 |
| [2] | Sun, Y., Han, L. and Strasser, P. (2020) A Comparative Perspective of Electrochemical and Photochemical Approaches for Catalytic H2O2 Production. Chemical Society Reviews, 49, 6605-6631. https://doi.org/10.1039/d0cs00458h |
| [3] | Wang, L., Zhang, J., Zhang, Y., Yu, H., Qu, Y. and Yu, J. (2022) Inorganic Metal-Oxide Photocatalyst for H2O2 Production. Small, 18, Article 2104561. https://doi.org/10.1002/smll.202104561 |
| [4] | Wang, X., Blechert, S. and Antonietti, M. (2012) Polymeric Graphitic Carbon Nitride for Heterogeneous Photocatalysis. ACS Catalysis, 2, 1596-1606. https://doi.org/10.1021/cs300240x |
| [5] | Wang, P., Fan, S., Li, X., Duan, J. and Zhang, D. (2023) Modulating the Molecular Structure of Graphitic Carbon Nitride for Identifying the Impact of the Piezoelectric Effect on Photocatalytic H2O2 Production. ACS Catalysis, 13, 9515-9523. https://doi.org/10.1021/acscatal.3c02565 |
| [6] | Shiraishi, Y., Kanazawa, S., Sugano, Y., Tsukamoto, D., Sakamoto, H., Ichikawa, S., et al. (2014) Highly Selective Production of Hydrogen Peroxide on Graphitic Carbon Nitride (g-C3N4) Photocatalyst Activated by Visible Light. ACS Catalysis, 4, 774-780. https://doi.org/10.1021/cs401208c |
| [7] | Wang, Z., Wu, J., Fan, X., Zhang, Y., Xu, Q., Qiu, B., et al. (2024) Green and Alcohol-Free H2O2 Generation Paired with Simultaneous Contaminant Treatment Enabled by Sulfur/Cyano-Modified g-C3N4 with Efficient Oxygen Activation and Proton Adsorption. Green Chemistry, 26, 2730-2739. https://doi.org/10.1039/d3gc04123a |
| [8] | Shiraishi, Y., Kofuji, Y., Sakamoto, H., Tanaka, S., Ichikawa, S. and Hirai, T. (2015) Effects of Surface Defects on Photocatalytic H2O2 Production by Mesoporous Graphitic Carbon Nitride under Visible Light Irradiation. ACS Catalysis, 5, 3058-3066. https://doi.org/10.1021/acscatal.5b00408 |
| [9] | Gao, T., Zhao, D., Yuan, S., Zheng, M., Pu, X., Tang, L., et al. (2024) Energy Band Engineering of Graphitic Carbon Nitride for Photocatalytic Hydrogen Peroxide Production. Carbon Energy, 6, e596. https://doi.org/10.1002/cey2.596 |
| [10] | Liu, L.L., Chen, F., Wu, J.H., et al. (2023) Synergy of Crystallinity Modulation and Intercalation Engineering in Carbon Nitride for Boosted H2O2 Photosynthesis. Proceedings of the National Academy of Sciences, 120, e2215305120. https://doi.org/10.1073/pnas.2215305120 |
| [11] | Song, J., Li, C., Zhang, X., Ma, P. and Zheng, K. (2025) Hydrogen Peroxide Production with Photocatalysts Based on Carbon Nitride: Evaluation Criteria, Reaction Mechanism, Improvement Scheme, and Development Opportunity. ACS Catalysis, 15, 9058-9088. https://doi.org/10.1021/acscatal.5c01609 |
| [12] | Zhao, H., Jin, Q., Khan, M.A., Larter, S., Siahrostami, S., Kibria, M.G., et al. (2022) Rational Design of Carbon Nitride for Remarkable Photocatalytic H2O2 Production. Chem Catalysis, 2, 1720-1733. https://doi.org/10.1016/j.checat.2022.04.015 |
| [13] | Zhang, P., Tong, Y., Liu, Y., Vequizo, J.J.M., Sun, H., Yang, C., et al. (2020) Heteroatom Dopants Promote Two-Electron O2 Reduction for Photocatalytic Production of H2O2 on Polymeric Carbon Nitride. Angewandte Chemie, 132, 16343-16351. https://doi.org/10.1002/ange.202006747 |
| [14] | Lv, H., Li, Z., Yin, P., Wan, P. and Zhu, M. (2025) Recent Progress on Non-Metallic Carbon Nitride for the Photosynthesis of H2O2: Mechanism, Modification and In-Situ Applications. Chinese Chemical Letters, 36, Article 110457. https://doi.org/10.1016/j.cclet.2024.110457 |
| [15] | Ma, L., Gao, Y., Wei, B., Huang, L., Zhang, N., Weng, Q., et al. (2024) Visible-Light Photocatalytic H2O2 Production Boosted by Frustrated Lewis Pairs in Defected Polymeric Carbon Nitride Nanosheets. ACS Catalysis, 14, 2775-2786. https://doi.org/10.1021/acscatal.3c05360 |
| [16] | Cui, Y., Ding, Z., Liu, P., Antonietti, M., Fu, X. and Wang, X. (2012) Metal-Free Activation of H2O2 by g-C3N4 under Visible Light Irradiation for the Degradation of Organic Pollutants. Physical Chemistry Chemical Physics, 14, 1455-1462. https://doi.org/10.1039/c1cp22820j |
| [17] | Li, J., Huang, J., Zeng, G., Zhang, C., Yu, H., Wan, Q., et al. (2023) Efficient Photosynthesis of H2O2 via Two-Electron Oxygen Reduction Reaction by Defective g-C3N4 with Terminal Cyano Groups and Nitrogen Vacancies. Chemical Engineering Journal, 463, Article 142512. https://doi.org/10.1016/j.cej.2023.142512 |
| [18] | Tong, S., Zhang, X. and Yang, P. (2023) g-C3N4 Sheet Nanoarchitectonics with Island-Like Crystalline/Amorphous Homojunctions towards Efficient H2 and H2O2 Evolution. Environmental Research, 236, Article 116805. https://doi.org/10.1016/j.envres.2023.116805 |
