Molecular Dynamics Simulation of Acetylene Pyrolysis into Fullerenes

doi:10.6023/A23020026

Abstract

Acetylene (C₂H₂) is one of the main intermediate species in the industrial conversion of natural gas to many high-value chemicals. In this work, molecular dynamics simulation was carried out to study the possibility of producing fullerenes by high temperature pyrolysis of acetylene. The effect of atomic and molecular hydrogen, reaction temperature and carbon density were discussed according to the results obtained from reactive force filed molecular dynamics simulation. The results show that C₂H₂ can form fullerenes at suitable temperature and density. In the early stage, hydrogen in the system is conducive to the aggregation of small carbon clusters and the formation of carbon chains is faster. Interestingly, in the later stage, it is not conducive to further aggregation reaction, but the atomic and molecular hydrogen produced by C₂H₂ pyrolysis can make the carbon clusters rounder and prevent the excessive growth of the carbon clusters, and can make the carbon cage more similar to classical fullerenes, which suggest that the production of fullerenes from C₂H₂ does not require the assistance of inert gases, thus significantly reducing the production cost of fullerenes in principle. Two main pathways of fullerenes formation were observed in simulations under different conditions. The first pathway is from carbon chain, cluster to carbon cage, most occurring in low density conditions. The other pathway is from carbon chain, cluster, graphene and carbon cage, most occurring in high density conditions. The growth of six-membered rings during fullerene formation is realized mainly via carbon cage defects and bond rotation, and the general trend is to make the carbon cage closer to the classical fullerene. The preparation of fullerenes by C₂H₂ pyrolysis is worthy of further study. These results are helpful to understand the process of producing fullerenes from the pyrolysis of C₂H₂ and have important implications for the development of industrial production methods of fullerenes.

Key words: acetylene, pyrolysis, fullerene, molecular dynamics, formation mechanism

Cite this article

Zhenyu Liu, Li-Hua Gan. Molecular Dynamics Simulation of Acetylene Pyrolysis into Fullerenes[J]. Acta Chimica Sinica, 2023, 81(5): 502-510.

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Fig. & Tab. 15

Figure 1. Evolution of rings of (a) 150 C2H2 and (b) 300 C at 3500 K, 5 kg/m3 (averaged 3 times)

Figure 2. Evolution of components in different initial systems with the same carbon density at 3500 K (averaged 3 times) (a) 150 C2H2; (b) 300 C; (c) 300 C&150 H2; (d) 300 C&300 H; (e) 300 C&300 H2; (f) 300 C&600 H

Figure 3. (a) Formation process of C6 at 3500 K, 5 kg/m3, 150 C2H2 and 300 C (C6 is part of the carbon cage) and (b) evolution of H in carbon molecules in different initial input systems with the same carbon density at 3500 K (the number of H in carbon molecules is calculated as the total hydrogen number in the system minus the amount of H and H2, the data has been averaged 3 times)

Figure 4. Snapshots of 150 C2H2 and 300 C in 1000 ps

Figure 5. (a) Evolution of sp2-C (averaged 3 times) and (b) snapshots and the average number of carbon in the carbon cage of the three trajectories at 3 ns in different initial input systems with the same carbon density at 3500 K

System	N₅	N₆	N₅＋N₆	N_3-8	N₆/N_3-8	(N₅＋N₆)/N_3-8
150 C₂H₂	24	67	91	108	0.620	0.843
300 C	34	89	123	146	0.610	0.842
300 C&300 H	24	74	98	112	0.661	0.875
300 C&300 H₂	18	47	65	75	0.627	0.867
300 C&600 H	22	65	87	98	0.663	0.888

Table 1. Numbers of five-membered rings (N5), six-membered rings (N6), the total numbers of three-membered rings to eight-membered rings (N3-8) and (N5＋N6)/(N3-8) in different systems with the same carbon density at 3 ns and 3500 K (averaged 3 times)

Figure 6. Evolution of sp2-C at different temperatures (averaged 3 times)

Figure 7. Snapshots of 150 C2H2 in 3700 and 3900 K in 3 ns (Choose from the first of the three trajectories)

密度及编号	出现时间	组成	消失时间	组成	存在时长	H/C变化
5-4	1.450	C₉₀H₅	1.542	C₁₂₂H₈	0.092	0.010
25-2	0.540	C₁₂₄H₁₇	0.640	C₁₁₂H₁₁	0.100	－0.039
25-5	0.540	C₂₀₀H₂₄	0.825	C₂₄₇H₃₂	0.285	0.010
5-5	1.300	C₁₀₈H₅	1.850	C₁₈₃H₇	0.550	－0.008
50-5	0.500	C₂₂₉H₃₉	1.260	C₂₈₃H₂₆	0.760	－0.078
50-4	0.550	C₂₃₃H₃₉	1.510	C₂₈₄H₁₇	0.960	－0.108
25-7	0.790	C₁₆₂H₂₁	1.800	C₂₆₂H₁₄	1.010	－0.076
25-3	0.580	C₁₅₀H₂₂	1.680	C₂₇₇H₁₉	1.100	－0.078
50-2	0.620	C₂₀₄H₃₈	2.050	C₂₈₅H₁₈	1.430	－0.123
25-0	0.750	C₂₂₉H₃₆	2.190	C₂₈₃H₁₉	1.440	－0.090
25-4	0.617	C₁₆₂H₂₄	2.065	C₂₇₉H₁₇	1.448	－0.087
50-9	0.540	C₂₁₂H₄₃	1.990	C₂₈₃H₂₄	1.450	－0.118
25-8	0.700	C₁₉₉H₂₉	5.000	C₂₉₅H₁₄	4.300	－0.098

Table 2. Statistics on the trajectory of graphene at densities of 5, 25 and 50 kg/m3, 150 C2H2, 3500 K

Figure 8. Evolution of (a) C2H and (b) C2H2 at 3500 K, 150 C2H2 with the density of 5, 25 and 50 kg/m3 (averaged 10 times)

Figure 9. Number of the top ten reactions within 500 ps at 3500 K, 150 C2H2 with density of (a) 5, (b) 25 and (c) 50 kg/m3 (averaged 10 times)

Figure 10. Defects induced the change of six-membered rings Snapshots from the first trajectory of the three trajectories in 3300 K, 150 C2H2, 5 kg/m3. (a) defect shrinkage or expansion, (b) adsorption or detachment of carbon chains

Figure 11. Bond rotation induced the change of six-membered rings Snapshots from the first trajectory of the three trajectories in 3300 K, 150 C2H2, 5 kg/m3

Time/ps	δN₆	缺口收缩/扩大	碳链	键旋转
2520~2521	5	5
2521~2522	－2	－2
2523~2524	－1	－1
2524~2525	2	2
2526~2527	－2	－2
2527~2528	2	2
2528~2529	1		1
2529~2530	－1	－1
2530~2531	1	2		－1
2531~2532	0
2532~2533	1	1
2534~2535	－1	－2		1
2535~2536	3	2		1
2536~2537	－2		－2
2537~2538	1
2538~2539	1		2
2539~2540	－1			－1
2540~2541	3			3
总计	10	6	1	3

Table 3. Source of changes in 6-membered ring number (δN6) during 2520~2541 ps from the first trajectory of the three trajectories in 3300 K, 150 C2H2, 5 kg/m3

Figure 12. Snapshots of cage forming process at 3300 K, 150 C2H2, 5 kg/m3 and representative reactions

References 34

[1]	Xie, S.-Y.; Yang, S.-F.; Li, S.-H. Fullerenes: Fundamental and Application,Science Press, Beijing, 2019. (in Chinese)
	(谢素原, 杨上峰, 李姝慧, 富勒烯: 从基础到应用, 科学出版社, 北京, 2019.)
[2]	Gan, L.-H.; Wang, C.-R. Structure, Properties and Applications of Fullerenes and Their Derivatives, Chemical Industry Press, Beijing, 2019. (in Chinese)
	(甘利华, 王春儒, 富勒烯及其衍生物的结构、性质和应用, 化学工业出版社, 北京, 2019.)
[3]	Qiu, L.; Liang, J.-Y.; Zhang, Z.-X.; Wang, T.-S. Acta Chim. Sinica 2022, 80, 874. (in Chinese) doi: 10.6023/A22020087
	(邱玲, 梁家艺, 张竹霞, 王太山, 化学学报, 2022, 80, 874.) doi: 10.6023/A22020087
[4]	Wu, B.; Wang, C.; Li, B.-L.; Wang, C.-R. Acta Chim. Sinica 2022, 80, 101. (in Chinese) doi: 10.6023/A21120564
	(吴波, 王冲, 李宝林, 王春儒, 化学学报, 2022, 80, 101.) doi: 10.6023/A21120564
[5]	Ramazani, A.; Moghaddasi, M. A.; Malekzadeh, A. M.; Rezayati, S.; Hanifehpour, Y.; Joo, S. W. Inorg. Chem. Commun. 2021, 125, 108442. doi: 10.1016/j.inoche.2021.108442
[6]	Xue, X.-G.; Meng, L.-Y.; Ma, Y.; Zhang, C.-Y. J. Phys. Chem. C 2017, 121, 7502. doi: 10.1021/acs.jpcc.7b00294
[7]	Xu, H. M.S. Thesis, Southwest University, Chongqing, 2020. (in Chinese)
	(徐惠, 硕士论文, 西南大学, 重庆, 2020.)
[8]	Howard, J. B.; McKinnon, J. T.; Johnson, M. E.; Makarovsky, Y.; Lafleur, A. L. J. Phys. Chem. 1992, 96, 6657. doi: 10.1021/j100195a026
[9]	Homann, K. H. Angew. Chem., Int. Ed. 1998, 37, 2434. doi: 10.1002/(ISSN)1521-3773
[10]	Takehara, H.; Fujiwara, M.; Arikawa, M.; Diener, M. D.; Alford, J. M. Carbon 2005, 43, 311. doi: 10.1016/j.carbon.2004.09.017
[11]	Zhu, Y.; Zhang, G.; Zhang, W.; Lin, T.; Xie, H.; Liu, Q.; Zhang, H. J. Wuhan Univ. Technol. (Mater. Sci. Ed.) 2007, 22, 94.
[12]	Sharma, A.; Mukut, K. M.; Roy, S. P.; Goudeli, E. Carbon 2021, 180, 215. doi: 10.1016/j.carbon.2021.04.065
[13]	Wang, Y.; Gu, M.-Y.; Wu, J.-J.; Cao, L.; Lin, Y.-Y.; Huang, X. Y. Int. J. Hydrogen Energy 2021, 46, 36557. doi: 10.1016/j.ijhydene.2021.08.125
[14]	Zhao, J.; Lin, Y.-Y.; Huang, K.; Gu, M.-Y.; Lu, K.; Chen, P.; Wang, Y.; Zhu, B.-C. Fuel 2020, 262, 116677. doi: 10.1016/j.fuel.2019.116677
[15]	Han, S.; Li, X.; Nie, F.; Zheng, M.; Liu, X.; Guo, L. Energy Fuels 2017, 31, 8434. doi: 10.1021/acs.energyfuels.7b01194
[16]	Liu, Y.; Wei, X.; Sun, W.-Z.; Zhao, L. Energy Fuels 2021, 35, 16778. doi: 10.1021/acs.energyfuels.1c02462
[17]	Zhang, C.-Y.; Zhang, C.; Ma, Y.; Xue, X.-G. Phys. Chem. Chem. Phys. 2015, 17, 11469. doi: 10.1039/C5CP00926J
[18]	Zhong, R.; Hong, R. Chem. Eng. J. 2020, 387, 124102. doi: 10.1016/j.cej.2020.124102
[19]	Li, H. B.; Page, A. J.; Irle, S.; Morokuma, K. J. Phys. Chem. Lett. 2013, 4, 2323. doi: 10.1021/jz400925f
[20]	Van Duin, A. C.; Dasgupta, S.; Lorant, F.; Goddard, W. A. J. Phys. Chem. A 2001, 105, 9396. doi: 10.1021/jp004368u
[21]	Brenner, D. W. Phys. Rev. B 1990, 42, 9458. doi: 10.1103/PhysRevB.42.9458
[22]	Mao, Q.; Van Duin, A. C.; Luo, K. H. Carbon 2017, 121, 380. doi: 10.1016/j.carbon.2017.06.009
[23]	Yoon, K.; Rahnamoun, A.; Swett, J. L.; Iberi, V.; Cullen, D. A.; Vlassiouk, I. V.; Belianinov, A.; Jesse, S.; Sang, X.; Ovchinnikova, O. S.; Rondinone, A. J.; Unocic, R. R.; Van Duin, A. C. ACS Nano. 2016, 10, 8376. doi: 10.1021/acsnano.6b03036
[24]	Chen, J.; Pei, J.; Zhao, H. J. Phys. Chem. C 2021, 125, 19345. doi: 10.1021/acs.jpcc.1c02610
[25]	Mei, H.; Cui, J.; He, X.; Lu, Y.; Sun, X.; Xu, K.; Mei, X. J. Phys. Chem. C 2022, 126, 13388. doi: 10.1021/acs.jpcc.2c02784
[26]	Gaikwad, P. S.; Kowalik, M.; Jensen, B. D.; Van Duin, A.; Odegard, G. M. ACS Appl. Nano Mater. 2022, 5, 5915. doi: 10.1021/acsanm.2c01280
[27]	Qian, H. J.; van Duin, A. C.; Morokuma, K.; Irle, S. J. Chem. Theory Comput. 2011, 7, 2040. doi: 10.1021/ct200197v
[28]	Thompson, A. P.; Aktulga, H. M.; Berger, R.; Bolintineanu, D. S.; Brown, W. M.; Crozier, P. S.; in't Veld, P. J.; Kohlmeyer, A.; Moore, S. G.; Nguyen, T. D.; Shan, R.; Stevens, M. J.; Tranchida, J.; Trott, C.; Plimpton, S. J. Comp. Phys. Commun. 2022, 271, 108171. doi: 10.1016/j.cpc.2021.108171
[29]	Plimpton, S. J. Comput. Phys. 1995, 117, 1.
[30]	Hoover, W. G. Phys. Rev. A 1985, 31, 1695. doi: 10.1103/PhysRevA.31.1695
[31]	Humphrey, W.; Dalke, A.; Schulten, K. J. Mol. Graphics 1996, 14, 33. doi: 10.1016/0263-7855(96)00018-5
[32]	Qian, H. J.; Wang, Y.; Morokuma, K. Carbon 2017, 114, 635. doi: 10.1016/j.carbon.2016.12.062
[33]	Ma, J.; Chen, X.; Song, M.; Wang, C.; Xia, W. Diamond Relat. Mater. 2021, 117, 108445. doi: 10.1016/j.diamond.2021.108445
[34]	Saha, B.; Irle, S.; Morokuma, K. J. Phys. Chem. C 2011, 115, 22707. doi: 10.1021/jp203614e

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