The curvature structure unlocks an ultra-efficient metal-free carbon catalyst surpassing gold for acetylene hydrochlorination

doi:10.1016/S1872-2067(24)60250-0

Abstract

Abstract:

Metal-free carbon catalysts have garnered significant attention since their inception. Despite substantial advancements, including widely adopted strategies such as heteroatom doping and defect engineering, their catalytic performance remains inferior to that of metal-based catalysts. In this study, we have predicted and demonstrated that the curvature of carbon plays a pivotal role in the adsorption of acetylene and the overall catalytic performance. First-principles calculations suggest that a tip-enhanced local electric field at the defect site on the curved carbon catalyst enhances the reaction kinetics for acetylene hydrochlorination. The experimental results highlight the structural advantages of the curved defect site, revealing that high-curvature defective carbon (HCDC) demonstrates an adsorption capacity for acetylene that is almost two orders of magnitude higher than that of defective carbon. Notably, HCDC achieves an acetylene conversion of up to 90% at 220 °C under a gas hourly space velocity of 300 h^-1, significantly surpassing the performance of the benchmark 0.25% Au/AC catalyst. This proof-of-concept study reveals the fundamental mechanisms driving the superior performance of carbon catalysts with curved nanostructures and presents a straightforward, environmentally friendly method for large-scale production of carbon materials with precisely controlled nanostructures. It highlights the potential for commercializing metal-free carbon catalysts in acetylene hydrochlorination and related heterogenous catalytic reactions.

Key words: Metal-free, Carbon catalyst, Curvature, Acetylene hydrochlorination, Carbocatalysis

Shuhao Wei, Ye Chen, Yiyang Qiu, Wei Kong, Di Lin, Jiarong Li, Guojun Lan, Yi Jia, Xiucheng Sun, Zaizhe Cheng, Jian Liu, P. Hu, Ying Li. The curvature structure unlocks an ultra-efficient metal-free carbon catalyst surpassing gold for acetylene hydrochlorination[J]. Chinese Journal of Catalysis, 2025, 70: 260-271.

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URL: https://www.cjcatal.com/EN/10.1016/S1872-2067(24)60250-0

https://www.cjcatal.com/EN/Y2025/V70/I3/260

Figures/Tables 6

Fig. 1. Theoretical investigations. (a) The adsorbed energies of C2H2. (b) HCl on the plane, out-curved and in-curved surfaces. When the adsorbates are located on the outer side of the curved surface, the surface is called the outward curved surface (out-curved surface) in this work. When the adsorbates are on the inner side of the curved surface, the surface is referred to as the inward curved surface (in-curved surface). (c) The reaction pathways of acetylene hydrochlorination on the surfaces. Reaction states A, B, C, D, and E are described in the main text. Blue, white and grey balls indicate the N, H, and C atoms, respectively. Reaction pathway of acetylene hydrochlorination on N doped plane surface (d), out-curved surface (e), and in-curved surface (f). The reaction proceeds through the C2H2/HCl adsorption (A), co-adsorption of HCl and C2H2 (B), the transition state of C-Cl bond formation accompanied by the HCl activation (C), and VCM formation (D).

Fig. 2. (a) The preparation process of high-curvature defective carbon using PAN as the raw materials. (b) TEM image of HCDC. N2 adsorption-desorption isotherms (c) and pore size distributions (d) of carbon materials. XRD patterns (e) and Raman spectra (f) of DC and HCDC catalysts. XPS spectra of C 1s (g) and N 1s (h) of DC and HCDC catalysts.

Table 1 Textural properties and element composition of various carbon catalysts.

Catalyst	Surface area (m² g^-1)	Pore volume (cm³ g^-1)	Pore size ^a (nm)	Elemental composition (at%) ^b			I_D:I_G
Catalyst	Surface area (m² g^-1)	Pore volume (cm³ g^-1)	Pore size ^a (nm)	C	N	O	I_D:I_G
DC	1499	0.66	1.7	82.8	10.0	7.1	1.00
HCDC	108	0.19	6.9	82.4	11.4	6.2	1.00

Table 2 The relative contents of nitrogen species of catalysts are determined by XPS.

Catalyst	Pyridinic N (%)	Pyrrolic N (%)	Quaternary N (%)	Oxidized N (%)
DC	42.6	39.0	14.0	4.3
HCDC	42.1	38.5	16.0	3.3

Fig. 3. (a) Conversion of acetylene in the acetylene hydrochlorination reaction of DC and HCDC catalysts. Reaction conditions: Temperature: 220 °C, GHSV of C2H2 is 300 h-1, and V(HCl):V(C2H2) = 1.2:1. (b) Conversion of acetylene in the acetylene hydrochlorination reaction of HCDC catalysts at different temperature. GHSV of C2H2 is 300 h-1, and V(HCl):V(C2H2) = 1.2: 1. (c) Conversion of acetylene in the acetylene hydrochlorination reaction of DC and HCDC catalysts at different GHSV of C2H2. Temperature is 220 °C, and V(HCl):V(C2H2) = 1.2:1. (d) Conversion of acetylene in the acetylene hydrochlorination reaction of various catalysts we prepared. (e) The STY of VCM of reported catalysts and HCDC catalysts, the reference was listed in Supporting information. (f) The Conversion of acetylene of reported metal catalysts and HCDC catalyst [24????????-33]. (g) Stability test of HCDC catalyst for 200 h. Reaction conditions: 220 °C, GHSV of C2H2 is 30 h-1, and V(HCl):V(C2H2) = 1.2:1.

Fig. 4. The simulated velocity field of plane (a) and curved (b) model. (c) Simulated velocity distribution of C2H2 on the plotted line of models. The C2H2-TPD-MS (d), the adsorption of C2H2 (e) adsorbed in the per specific surface area of catalysts. (f) HCl-TPD-MS for HCDC and DC catalysts. The activation energy (g), reaction orders of HCl (h) and C2H2 (i) for HCDC and DC. Reaction conditions: catalyst (0.1 g), 220 °C, and ambient pressure. The concentrations of C2H2 and HCl from 10% to 25% balanced in N2 flow. The reaction order of both reactants is indicated by the slope of the fitting lines. (j) Radar plot charting the relation of the C2H2 conversion with key experimental indicators for the activity. (k) Adsorption diagram of C2H2 and HCl molecules on the surfaces of different catalysts.

References

[1]	X. Wang, W. Chen, X. Lei, C. Lei, N. Zhu, B. Huang, Coord. Chem. Rev., 2024, 500, 215541.
[2]	J. Zhong, Y. Xu, Z. Liu, Green Chem., 2018, 20, 2412-2427.
[3]	L. Feng, S. Ali, C. Xu, S. Cao, G. Tuci, G. Giambastiani, C. Pham-Huu, Y. Liu, ACS Catal., 2022, 12, 6119-6131.
[4]	S. Zhao, D.-W. Wang, R. Amal, L. Dai, Adv. Mater., 2019, 31, 1801526.
[5]	S. Wei, W. Kong, Y. Qiu, G. Lan, X. Sun, Z. Cheng, Y. Li, Carbon, 2024, 227, 119286.
[6]	K. Zhou, B. Li, Q. Zhang, J.-Q. Huang, G.-L. Tian, J.-C. Jia, M.-Q. Zhao, G.-H. Luo, D. S. Su, F. Wei, ChemSusChem, 2014, 7, 723-728.
[7]	X. Li, X. Pan, L. Yu, P. Ren, X. Wu, L. Sun, F. Jiao, X. Bao, Nat. Commun., 2014, 5, 3688.
[8]	X. Qiao, X. Liu, Z. Zhou, Q. Guan, W. Li, Catal. Sci. Technol., 2021, 11, 2327-2339.
[9]	F. Li, H. Zhang, M. Zhang, L. Li, L. Yao, W. Peng, J. Zhang, ACS Sustainable Chem. Eng., 2022, 10, 194-203.
[10]	Y. Lu, F. Lu, M. Zhu, J. Taiwan Inst. Chem. Eng., 2020, 113, 198-203.
[11]	S. Wei, Y. Qiu, X. Sun, X. Wang, H. Li, G. Lan, J. Liu, Y. Li, ACS Sustainable Chem. Eng., 2022, 10, 10476-10485.
[12]	Y. Qiu, S. Ali, G. Lan, H. Tong, J. Fan, H. Liu, B. Li, W. Han, H. Tang, H. Liu, Y. Li, Carbon, 2019, 146, 406-412.
[13]	G. Lan, Y. Qiu, J. Fan, X. Wang, H. Tang, W. Han, H. Liu, H. Liu, S. Song, Y. Li, Chem. Commun., 2019, 55, 1430-1433.
[14]	J. Wang, W. Gong, M. Zhu, B. Dai, Appl. Catal. A, 2018, 564, 72-78.
[15]	Y. Qiu, D. Fan, G. Lan, S. Wei, X. Hu, Y. Li, Chem. Commun., 2020, 56, 14877-14880.
[16]	X. Wang, C. Han, Y. Han, R. Huang, H. Sun, P. Guo, X. Liu, M. Huang, Y. Chen, H. Wu, J. Zhang, X. Yan, Z. Mao, A. Du, Y. Jia, L. Wang, Small, 2024, 20, 2401447.
[17]	N. Li, K. Guo, M. Li, X. Shao, Z. Du, L. Bao, Z. Yu, X. Lu, J. Am. Chem. Soc., 2023, 145, 24580-24589.
[18]	A. Lazaridou, L. R. Smith, S. Pattisson, N. F. Dummer, J. J. Smit, P. Johnston, G. J. Hutchings, Nat. Rev. Chem., 2023, 7, 287-295.
[19]	H. Chang, J. Luo, H. C. Liu, S. Zhang, J. G. Park, Z. Liang, S. Kumar, ACS Appl. Polym. Mater., 2019, 1, 1015-1021.
[20]	X. Liu, D. Lyu, C. Merlet, M. J. A. Leesmith, X. Hua, Z. Xu, C. P. Grey, A. C. Forse, Science, 2024, 384, 321-325.
[21]	M. Ghazinejad, S. Holmberg, O. Pilloni, L. Oropeza-Ramos, M. Madou, Sci. Rep., 2017, 7, 16551.
[22]	H. Jiang, J. Gu, X. Zheng, M. Liu, X. Qiu, L. Wang, W. Li, Z. Chen, X. Ji, J. Li, Energy Environ. Sci., 2019, 12, 322-333.
[23]	X. Qiao, C. Zhao, Z. Zhou, Q. Guan, W. Li, ACS Sustainable Chem. Eng., 2019, 7, 17979-17989.
[24]	Y. Yang, C. Zhao, X. Qiao, Q. Guan, W. Li, Green Energy Environ., 2023, 8, 1141-1153.
[25]	H. Li, B. Wu, J. Wang, F. Wang, X. Zhang, G. Wang, H. Li, Chin. J. Catal., 2018, 39, 1770-1781.
[26]	X. Wang, G. Lan, Z. Cheng, W. Han, H. Tang, H. Liu, Y. Li, Chin. J. Catal., 2020, 41, 1683-1691.
[27]	H. Zhang, W. Li, Y. Jin, W. Sheng, M. Hui, X. Wang, J. Zhang, Appl. Catal. B, 2016, 189, 56-64.
[28]	B. Wang, C. Jin, S. Shao, Y. Yue, Y. Zhang, S. Wang, R. Chang, H. Zhang, J. Zhao, X. Li, Green Energy Environ., 2023, 8, 1128-1140.
[29]	M. Zhang, H. Zhang, F. Li, L. Yao, W. Peng, J. Zhang, Catal. Sci. Technol., 2022, 12, 4255-4265.
[30]	Y. Dong, H. Zhang, W. Li, M. Sun, C. Guo, J. Zhang, J. Ind. Eng. Chem., 2016, 35, 177-184.
[31]	J. Zhao, S. Wang, B. Wang, Y. Yue, C. Jin, J. Lu, Z. Fang, X. Pang, F. Feng, L. Guo, Z. Pan, X. Li, Chin. J. Catal., 2021, 42, 334-346.
[32]	X. Dong, G. Liu, Z. Chen, Q. Zhang, Y. Xu, Z. Liu, Chin. J. Catal., 2023, 46, 137-147.
[33]	K. Zhou, W. Wang, Z. Zhao, G. Luo, J. T. Miller, M. S. Wong, F. Wei, ACS Catal., 2014, 4, 3112-3116.
[34]	H. Xu, G. Luo, J. Ind. Eng. Chem., 2018, 65, 13-25.
[35]	Z. Deng, M. Gong, Z. Gong, X. Wang, Nano Lett., 2022, 22, 9551-9558.
[36]	Q.-X. Chen, Y.-H. Liu, Z. He, J.-L. Wang, J.-W. Liu, H.-J. Jiang, W.-R. Huang, G.-Y. Gao, Z.-H. Hou, S.-H. Yu, J. Am. Chem. Soc., 2021, 143, 12600-12608.