Modulation of electronic structure of metal-free graphdiyne via precise nitrogen modification for oxygen evolution reaction

Abstract

The oxygen evolution reaction (OER) is essential for energy conversion and storage but is hindered by sluggish kinetics, low efficiency, and high overpotentials. Although RuO₂ and IrO₂ are efficient catalysts, their high cost and scarcity limit their large-scale application. In contrast, nonmetallic catalysts have gained traction as promising alternatives due to their cost-effectiveness, high stability, and environmental sustainability. The OER efficiency depends on optimal adsorption/desorption of oxygen intermediates, such as^∗O, OH^∗, and OOH^∗, on the catalyst surface. The electronic structure of carbon materials can be optimized via nitrogen doping, which introduces a higher polarity than carbon atoms, thereby optimizing the adsorption free energy of oxygen species during an OER. However, conventional high-temperature pyrolysis methods suffer from limitations such as inaccuracy and high energy consumption. The unique and facile bottom-up synthesis of graphdiyne (GDY) enables precise control over the doping positions of the three sp²-N atoms in GDY (1NGDY, 2NGDY, and 3NGDY) via monomer design engineering. By integrating density functional theory (DFT) calculations with experimental validation, we tailored the adsorption free energy of the oxygen intermediates in the OER, thereby optimizing the rate-determining step of^∗OOH generation. Among these three kinds of nitrogen-doped GDY catalysts, 3NGDY which incorporates three sp2-N atoms exhibited the optimal electrocatalytic performance, achieving a current density of 10 mA cm⁻² in 1 M KOH with a low overpotential of approximately 310 mV. This study demonstrates the significant potential of GDY-based metal-free catalysts in the development of cost-effective, high-performance electrocatalysts.

Keywords

Oxygen evolution reaction / Graphdiyne / Metal-free catalysts / N-doping graphdiyne

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

CRediT authorship contribution statement

Mei Wang: Writing – review & editing, Visualization, Supervision, Resources, Funding acquisition, Conceptualization. Xinliang Fu: Writing – original draft, Validation, Investigation, Data curation. Mengyu Lu: Investigation, Data curation. Guodong Shi: Investigation, Data curation. Xiufan Liu: Software, Investigation. Mingjian Yuan: Writing – review & editing, Validation, Supervision, Software, Resources, Project administration, Investigation, Funding acquisition, Conceptualization.

Acknowledgements

This study was financially supported by the National Natural Science Foundation of China (Grant No. 22375148). The authors acknowledge the financial support from The National Science Fund for Distinguished Young Scholars (Grant No. T2225024), National Key Research and Development Program of China (Grant No. 2022YFE0201500), National Natural Science Foundation of China (Grant Nos. 91956130 and 62104116), and Innovation and Technology Commission (Grant No. MHP/104/21), Shenzhen Science Technology and Innovation Commission (Grant No. JCYJ20210324125612035), and Natural Science Foundation of Henan (Grant No. 242300421442).

References

[1] C. Rong, K. Dastafkan, Y. Wang, C. Zhao, Breaking the activity and stability bottlenecks of electrocatalysts for oxygen evolution reactions in acids, Adv. Mater. 35 (2023) 2211884, doi: 10.1002/adma.202211884.

[2] W. Zhu, X. Song, F. Liao, H. Huang, Q. Shao, K. Feng, Y. Zhou, M. Ma, J. Wu, H. Yang, H. Yang, M. Wang, J. Shi, J. Zhong, T. Cheng, M. Shao, Y. Liu, Z. Kang, Stable and oxidative charged Ru enhance the acidic oxygen evolution reaction activity in two-dimensional ruthenium-iridium oxide, Nat. Commun. 14 (2023) 5365, doi: 10.1038/s41467-023-41036-9.

[3] H. Li, J.H. Lim, Y. Lv, N. Li, B. Kang, J.Y. Lee, Graphynes and graphdiynes for energy storage and catalytic utilization: Theoretical insights into recent advances, Chem. Rev. 123 (2023) 4795-4854, doi: 10.1021/acs.chemrev.2c00729.

[4] Y. Xie, X. Chen, K. Sun, J. Zhang, W.H. Lai, H. Liu, G. Wang, Direct oxygen-oxygen cleavage through optimizing interatomic distances in dual single-atom electrocatalysts for efficient oxygen reduction reaction, Angew. Chem. Int. Ed. 62 (2023) e202301833, doi: 10.1002/anie.202301833.

[5] O. van der Heijden, S. Park, J.J.J. Eggebeen, M.T.M. Koper, Non-kinetic effects convolute activity and tafel analysis for the alkaline oxygen evolution reaction on NiFeOOH electrocatalysts, Angew. Chem. Int. Ed. 62 (2023) e202216477, doi: 10.1002/anie.202216477.

[6] R. Qin, G. Chen, X. Feng, J. Weng, Y. Han, Ru/Ir-based electrocatalysts for oxygen evolution reaction in acidic conditions: From mechanisms, optimizations to challenges, Adv. Sci. 11 (2024) 2309364, doi: 10.1002/advs.202309364.

[7] M. Zhao, L. Jiang, Q. Yu, Environmental applications of single-atom catalysts based on graphdiyne, Catal. Sci. Technol. 13 (2023) 5154-5174, doi: 10.1039/D3CY00240C.

[8] X. Zhang, G. Han, S. Zhu, Flash nitrogen-doped carbon nanotubes for energy storage and conversion, Small 20 (2024) 2305406, doi: 10.1002/smll.202305406.

[9] A. Torres-Pinto, A.M. Díez, C.G. Silva, J.L. Faria, M.Á. Sanromán, A.M.T. Silva, M. Pazos, Tuning graphitic carbon nitride (g-C₃N₄) electrocatalysts for efficient oxygen evolution reaction (OER) , Fuel 360 (2024) 130575, doi: 10.1016/j.fuel.2023.130575.

[10] L. Zhang, L.L. Liu, J.J. Feng, A.J. Wang, Methanol-induced assembly and pyrolysis preparation of three-dimensional N-doped interconnected open carbon cages supported FeNb₂O₆ nanoparticles for boosting oxygen reduction reaction and Zn-air battery , J. Colloid Interface Sci. 661 (2024) 102-112, doi: 10.1016/j.jcis.2024.01.154.

[11] N. Kumaresan, P. Karuppasamy, M.P. Kumar, S.G. Peera, M.S. AlSalhi, S. Devanesan, R.V. Mangalaraja, P. Ramasamy, T.F. de Oliveira, G. Murugadoss, Synthesis and characterization of metal-free nanosheets of carbo-catalysts for bifunctional electrocatalyst towards HER and OER application, Mol. Catal. 539 (2023) 113043, doi: 10.1016/j.mcat.2023.113043.

[12] G. Yasin, S. Ibraheem, S. Ali, M. Arif, S. Ibrahim, R. Iqbal, A. Kumar, M. Tabish, M.A. Mushtaq, A. Saad, H. Xu, W. Zhao, Defects-engineered tailoring of tri-doped interlinked metal-free bifunctional catalyst with lower gibbs free energy of OER/HER intermediates for overall water splitting, Mater. Today Chem. 23 (2022) 100634, doi: 10.1016/j.mtchem.2021.100634.

[13] H.C. Huang, J. Li, Y. Zhao, J. Chen, Y.X. Bu, S.B. Cheng, Adsorption energy as a promising single-parameter descriptor for single atom catalysis in the oxygen evolution reaction, J. Mater. Chem. A 9 (2021) 6442-6450, doi: 10.1039/D0TA12567A.

[14] Y. Zhao, N. Yang, H. Yao, D. Liu, L. Song, J. Zhu, S. Li, L. Gu, K. Lin, D. Wang, Stereodefined codoping of sp-N and S atoms in few-layer graphdiyne for oxygen evolution reaction, J. Am. Chem. Soc. 141 (2019) 7240-7244, doi: 10.1021/jacs.8b13695.

[15] B. Wang, C. Cheng, M. Jin, J. He, H. Zhang, W. Ren, J. Li, D. Wang, Y. Li, A site distance effect induced by reactant molecule matchup in single-atom catalysts for fenton-like reactions, Angew. Chem. Int. Ed. 61 (2022) e202207268, doi: 10.1002/anie.202207268.

[16] X. Fu, X. Zhao, T.B. Lu, M. Yuan, M. Wang, Graphdiyne-based single-atom catalysts with different coordination environments, Angew. Chem. Int. Ed. 62 (2023) e202219242, doi: 10.1002/anie.202219242.

[17] Y. Ding, W. Zhou, J. Gao, F. Sun, G. Zhao, H₂O₂ electrogeneration from O₂ electroreduction by N-doped carbon materials: A mini-review on preparation methods, selectivity of N sites, and prospects , Adv. Mater. Interfaces 8 (2021) 2002091, doi: 10.1002/admi.202002091.

[18] M. Wang, J. Pu, Y. Hu, Y. Zi, Z.G. Wu, W. Huang, Functional graphdiyne for emerging applications: Recent advances and future challenges, Adv. Funct. Mater. 34 (2024) 2308601, doi: 10.1002/adfm.202308601.

[19] Z. Zheng, L. Qi, Y. Gao, X. Luan, Y. Xue, F. He, Y. Li, Ir₀/graphdiyne atomic interface for selective epoxidation , Nat. Sci. Rev. 10 (2023) nwad156, doi: 10.1093/nsr/nwad156.

[20] Y. Li, W. Nong, Z. Zeng, C. Wang, Degradation mechanism and enhancing strategies of oxygen reduction reaction catalyzed by carbon-based metal free catalysts in acidic solution, Adv. Energy Mater. 13 (2023) 2203159, doi: 10.1002/aenm.202203159.

[21] Z. Yang, X. Shen, N. Wang, J. He, X. Li, X. Wang, Z. Hou, K. Wang, J. Gao, T. Jiu, C. Huang, Graphdiyne containing atomically precise N atoms for efficient anchoring of lithium ion, ACS Appl. Mater. Interfaces 11 (2018) 2608-2617, doi: 10.1021/acsami.8b01823.

[22] J. He, N. Wang, Z. Cui, H. Du, L. Fu, C. Huang, Z. Yang, X. Shen, Y. Yi, Z. Tu, Y. Li, Hydrogen substituted graphdiyne as carbon-rich flexible electrode for lithium and sodium ion batteries, Nat. Commun. 8 (2017) 1172, doi: 10.1038/s41467-017-01202-2.

[23] H. Shang, Z. Zuo, H. Zheng, K. Li, Z. Tu, Y. Yi, H. Liu, Y. Li, Y. Li, N-doped graphdiyne for high-performance electrochemical electrodes, Nano Energy 44 (2018) 144-154, doi: 10.1016/j.nanoen.2017.11.072.

[24] Q. Lv, N. Wang, W. Si, Z. Hou, X. Li, X. Wang, F. Zhao, Z. Yang, Y. Zhang, C. Huang, Pyridinic nitrogen exclusively doped carbon materials as efficient oxygen reduction electrocatalysts for Zn-air batteries, Appl. Catal., B 261 (2020) 118234, doi: 10.1016/j.apcatb.2019.118234.

[25] X. Kan, Y. Ban, C. Wu, Q. Pan, H. Liu, J. Song, Z. Zuo, Z. Li, Y. Zhao, Interfacial synthesis of conjugated two-dimensional N-graphdiyne, ACS Appl. Mater. Interfaces 10 (2017) 53-58, doi: 10.1021/acsami.7b17326.

[26] Z. Zheng, Y. Xue, Y. Gao, Z. Wang, S. Zhao, X. Luan, F. He, Y. Li, Electronic structure modulation of metal-free graphdiyne for acidic oxygen evolution reaction, 2D Mater. 9 (2022) 014008, doi: 10.1088/2053-1583/ac4570.

[27] S. Zhang, Y. Cai, H. He, Y. Zhang, R. Liu, H. Cao, M. Wang, J. Liu, G. Zhang, Y. Li, H. Liu, B. Li, Heteroatom doped graphdiyne as efficient metal-free electrocatalyst for oxygen reduction reaction in alkaline medium, J. Mater. Chem. A 4 (2016) 4738-4744, doi: 10.1039/c5ta10579j.

[28] R. Wang, Z. Zhang, J. Suo, L. Liao, L. Li, Z. Yu, H. Zhang, V. Valtchev, S. Qiu, Q. Fang, Exploring metal-free ionic covalent organic framework nanosheets as efficient OER electrocatalysts via cationic-π interactions, Chem. Eng. J. 478 (2023) 147403, doi: 10.1016/j.cej.2023.147403.

[29] J. Ni, Z. Shi, Y. Wang, J. Yang, H. Wu, P. Wang, M. Xiao, C. Liu, W. Xing, Development of noble metal-free electrocatalysts towards acidic water oxidation: From fundamental understanding to state-of-the-art catalysts, eScience (2024) 100295, doi: 10.1016/j.esci.2024.100295.

[30] Y. Liu, Y. Xue, H. Yu, L. Hui, B. Huang, Y. Li, Graphdiyne ultrathin nanosheets for efficient water splitting, Adv. Funct. Mater. 31 (2021) 2010112, doi: 10.1002/adfm.202010112.

[31] Y. Kuang, R. He, X. Gu, F. Yang, X. Tian, L. Feng, High polarity catalyst of CoFe alloy/fluoride interconnected by bamboo-like nitrogen-doped carbon nanotubes for efficient oxygen evolution reaction, Chem. Eng. J. 456 (2023) 141055, doi: 10.1016/j.cej.2022.141055.

[32] C. Xing, Y. Xue, B.Huang Y, H. Yu, L. Hui, Y. Fang, Y. Liu, Y. Zhao, Z. Li, Y. Li, Fluorographdiyne: A metal-free catalyst for applications in water reduction and oxidation, Angew. Chem. Int. Ed. 58 (2019) 13897-13903, doi: 10.1002/anie.201905729.

[33] Y. Zhao, J. Wan, H. Yao, L. Zhang, K. Lin, L. Wang, N. Yang, D. Liu, L. Song, J. Zhu, L. Gu, L. Liu, H. Zhao, Y. Li, D. Wang, Few-layer graphdiyne doped with sp-hybridized nitrogen atoms at acetylenic sites for oxygen reduction electrocatalysis, Nat. Chem. 10 (2018) 924-931, doi: 10.1038/s41557-018-0100-1.

[34] X. Li, C. Deng, Y. Kong, Q. Huo, L. Mi, J. Sun, J. Cao, J. Shao, X. Chen, W. Zhou, Unlocking the transition of electrochemical water oxidation mechanism induced by heteroatom doping, Angew. Chem. Int. Ed. 62 (2023) e202309732, doi: 10.1002/anie.202309732.

[35] M. Cai, Q. Zhu, X. Wang, Z. Shao, L. Yao, H. Zeng, X. Wu, J. Chen, K. Huang, S. Feng, Formation and stabilization of NiOOH by introducing 𝛼-FeOOH in LDH: Composite electrocatalyst for oxygen evolution and urea oxidation reactions, Adv. Mater. 35 (2023) 2209338, doi: 10.1002/adma.202209338.

[36] Q. Ma, S. Mu, Acidic oxygen evolution reaction: Mechanism, catalyst classification, and enhancement strategies, Interdiscip. Mater. 2 (2023) 53-90, doi: 10.1002/idm2.12059.

[37] Y. Zhang, X. Mu, Z. Liu, H. Zhao, Z. Zhuang, Y. Zhang, S. Mu, S. Liu, D. Wang, Z. Dai, Twin-distortion modulated ultra-low coordination PtRuNi-O x catalyst for enhanced hydrogen production from chemical wastewater , Nat. Commun. 15 (2024) 10149, doi: 10.1038/s41467-024-54513-6.

[38] L. Hui, Y. Xue, B. Huang, H. Yu, C. Zhang, D. Zhang, D. Jia, Y. Zhao, Y. Li, H. Liu, Y. Li, Overall water splitting by graphdiyne-exfoliated and -sandwiched layered double-hydroxide nanosheet arrays, Nat. Commun. 9 (2018) 5309, doi: 10.1038/s41467-018-07790-x.

[39] Z. Tao, N. Lv, H. Zhao, X. Luo, Z. Li, J. Yu, L. Chen, X. Liu, S. Mu, Dual active site-mediated Ir single-atom-doped RuO₂ catalysts for highly efficient and stable water splitting , Chem. Sci. 15 (2024) 16796-16803, doi: 10.1039/D4SC04909H.