纳米管壁数对氮掺杂碳纳米管氧还原反应活性的影响

doi:10.16085/j.issn.1000-6613.2021-0910

摘要/Abstract

摘要：

通过预氧化和氨水水热法在含有不同壁数的碳纳米管表面成功引入含氮基团，从而获得了氮掺杂碳纳米管（NCNT），并研究了纳米管壁数对不同NCNT氧还原反应活性的影响。研究表明，各NCNT中氮元素的含量和含氮基团的种类相似，但不同含氮基团的比例则相差较大，其中平均壁数为2.5的NCNT样品含有最低的吡啶氮和石墨氮比例，而该样品却展现出最高的电子转移数和最大的氧还原反应极限扩散电流。分析表明，NCNT的氧还原反应活性决定于纳米管壁数，而不是吡啶氮和石墨氮活性基团的比例，即NCNT的内壁为反应电荷的转移提供了有效导电途径，并通过隧穿效应将电子转移到外壁，而外壁的含氮基团活性位点得到电子从而将O₂转变为OH^-。随着NCNT壁数的增加，NCNT中电子隧穿效应减弱，NCNT的氧还原反应（ORR）活性也随之降低。

关键词: 氮掺杂碳纳米管, 纳米管壁数, 氧还原反应, 碱性, 隧穿效应

Abstract:

Nitrogen-doped carbon nanotubes (NCNT) were prepared by introducing nitrogen-containing groups into surface of carbon nanotubes of different wall numbers using the pre-oxidation treatment and the ammonia hydrothermal method. Effect of carbon nanotube wall number on the electro-catalytic activity of NCNT for oxygen reduction reaction (ORR) was investigated. X-ray photoelectronic spectroscopy showed that the nitrogen content and the types of nitrogen-containing groups of each NCNT was similar. On the contrary, the content of different nitrogen-containing groups in each NCNT was quite different. Among them, the NCNT sample with an average wall number of 2.5 exhibited the lowest contents of pyridine nitrogen and graphite nitrogen, whereas it exhibited the highest ORR activity in terms of the most positive half-wave potential and the highest limiting current density. This indicated that the ORR activity of NCNT was decided by the number of walls of NCNT, rather than that of pyridine nitrogen and graphite nitrogen active groups when the samples had the similar nitrogen content. For this sample, the inner layer provided an effective conductive path to transfer electrons from the inner layer to the outer layer through the tunneling effect, and then the active sites of the nitrogen-containing groups on the outer wall converted O₂ to OH^-. Nevertheless, the tunneling effect became weaker with increasing the wall number of NCNT, leading to the decrease of the ORR activity of NCNT.

Key words: nitrogen-doped carbon nanotubes (CNT), wall number, oxygen reduction reaction (ORR), alkaline solution, tunneling effect

中图分类号:

TM911

张爱京, 江胜娟, 周明正, 柴茂荣, 张劲. 纳米管壁数对氮掺杂碳纳米管氧还原反应活性的影响[J]. 化工进展, 2022, 41(4): 2038-2045.

ZHANG Aijing, JIANG Shengjuan, ZHOU Mingzheng, CHAI Maorong, ZHANG Jin. Effect of wall number on the electro-catalytic activity of nitrogen-doped carbon nanotubes for oxygen reduction reaction[J]. Chemical Industry and Engineering Progress, 2022, 41(4): 2038-2045.

图/表 7

图1 NCNT制备的示意图

图2 NCNT的TEM图和平均壁数统计图（插图为不同NCNT的高分辨率TEM图）

图3 NCNT的XPS图和高分辨N 1s XPS图以及分峰拟合图

表1 XPS表征获得的NCNT样品中的元素组成（原子分数）以及不同含N基团所占比例（原子分数）

样品编号	I_D/I_G	O/%	C/%	N/%	吡啶氮/%	吡咯氮/%	石墨氮/%	吡啶氧化氮/%
NCNTs-1	0.6	5.18	91.22	3.6	19	53.32	22.05	5.63
NCNTs-2	0.8	5.64	90.91	3.45	7.04	75.05	8.11	9.8
NCNTs-3	1.4	6.11	89.79	4.09	17.63	60.02	20.08	2.08
NCNTs-4	1.6	6.87	89.49	3.64	15.74	66	17.5	0.75
NCNTs-5	1.9	5.5	90.62	3.88	18.41	67.18	2.83	11.57

图4 不同样品在不同转速下的线性扫描伏安法曲线（扫描速率10mV·s-1）

图5 不同NCNT样品在1600r/min下的线性扫描伏安曲线、半波电势和电子转移数

图6 NCNT的ORR反应机理示意图

参考文献 21

1	WU X, CHENG Y, VEDER J P, et al. An efficient bio-inspired oxygen reduction reaction catalyst: MnO _x nanosheets incorporated iron phthalocyanine functionalized graphene[J]. Energy & Environmental Materials, 2021, 4(3): 474-480.
2	CHENG Y, WU X, VEDER J P, et al. Tuning the electrochemical property of the ultrafine metal-oxide nanoclusters by iron phthalocyanine as efficient catalysts for energy storage and conversion[J]. Energy & Environmental Materials, 2019, 2(1): 5-17.
3	费慧龙, 段镶锋. 氮掺杂石墨炔用于氧还原反应[J]. 物理化学学报, 2019, 35(6): 559-560.
	FEI Huilong, DUAN Xiangfeng. Nitrogen doped graphdiyne enhances oxygen reduction reactions[J]. Acta Physico-Chimica Sinica, 2019, 35(6): 559-560.
4	CHOI E Y, KIM D E, LEE S Y, et al. Electrocatalytic activity of nitrogen-doped holey carbon nanotubes in oxygen reduction and evolution reactions and their application in rechargeable zinc-air batteries[J]. Carbon, 2020, 166: 245-255.
5	RAO C V, CABRERA C R, ISHIKAWA Y. In search of the active site in nitrogen-doped carbon nanotube electrodes for the oxygen reduction reaction[J]. The Journal of Physical Chemistry Letters, 2010, 1(18): 2622-2627.
6	SHARIFI T, HU G, JIA X, et al. Formation of active sites for oxygen reduction reactions by transformation of nitrogen functionalities in nitrogen-doped carbon nanotubes[J]. ACS Nano, 2012, 6(10): 8904-8912.
7	XU Z Y, ZHOU Z Y, LI B Y, et al. Identification of efficient active sites in nitrogen-doped carbon nanotubes for oxygen reduction reaction[J]. The Journal of Physical Chemistry C, 2020, 124(16): 8689-8696.
8	ZHANG J, LU S F, XIANG Y, et al. Intrinsic effect of carbon supports on the activity and stability of precious metal based catalysts for electrocatalytic alcohol oxidation in fuel cells: a review[J]. ChemSusChem, 2020, 13(10): 2484-2502.
9	CHENG Y, ZHANG J, JIANG S P. Are metal-free pristine carbon nanotubes electrocatalytically active?[J]. Chemical Communications, 2015, 51(72): 13764-13767.
10	CHENG Y, MEMAR A, SAUNDERS M, et al. Dye functionalized carbon nanotubes for photoelectrochemical water splitting-role of inner tubes[J]. Journal of Materials Chemistry A, 2016, 4(7): 2473-2483.
11	KALBAC M, GREEN A A, HERSAM M C, et al. Probing charge transfer between shells of double-walled carbon nanotubes sorted by outer-wall electronic type[J]. Chemistry: a European Journal, 2011, 17(35): 9806-9815.
12	CHENG Y, XU C W, JIA L C, et al. Pristine carbon nanotubes as non-metal electrocatalysts for oxygen evolution reaction of water splitting[J]. Applied Catalysis B: Environmental, 2015, 163: 96-104.
13	YUAN W Y, CHENG Y, SHEN P K, et al. Significance of wall number on the carbon nanotube support-promoted electrocatalytic activity of Pt NPs towards methanol/formic acid oxidation reactions in direct alcohol fuel cells[J]. Journal of Materials Chemistry A, 2015, 3(5): 1961-1971.
14	ZHANG J, CHENG Y, LU S F, et al. Significant promotion effect of carbon nanotubes on the electrocatalytic activity of supported Pd NPs for ethanol oxidation reaction of fuel cells: the role of inner tubes[J]. Chemical Communications, 2014, 50(89): 13732-13734.
15	LOPEZ-BEZANILLA A. Electronic and quantum transport properties of substitutionally doped double-walled carbon nanotubes[J]. The Journal of Physical Chemistry C, 2014, 118(3): 1472-1477.
16	CHEN P, XIAO T Y, QIAN Y H, et al. A nitrogen-doped graphene/carbon nanotube nanocomposite with synergistically enhanced electrochemical activity[J]. Advanced Materials, 2013, 25(23): 3192-3196.
17	ZHANG J, LU S F, XIANG Y, et al. Carbon-nanotubes-supported Pd nanoparticles for alcohol oxidations in fuel cells: effect of number of nanotube walls on activity[J]. ChemSusChem, 2015, 8(17): 2956-2966.
18	YOKOYAMA K, YOKOYAMA S, SATO Y, et al. Efficiency and long-term durability of a nitrogen-doped single-walled carbon nanotube electrocatalyst synthesized by defluorination-assisted nanotube-substitution for oxygen reduction reaction[J]. Journal of Materials Chemistry A, 2016, 4(23): 9184-9195.
19	GANGULY D, SUNDARA R, RAMANUJAM K. Chemical vapor deposition-grown nickel-encapsulated N-doped carbon nanotubes as a highly active oxygen reduction reaction catalyst without direct metal-nitrogen coordination[J]. ACS Omega, 2018, 3(10): 13609-13620.
20	许智慧, 沈丽明, 吴强, 等. 热解聚苯胺/碳纳米笼复合物制备氮掺杂碳材料及其氧还原性能研究[J]. 化学学报, 2015, 73(8): 793-798.
	XU Zhihui, SHEN Liming, WU Qiang, et al. Oxygen reduction performance of the nitrogen-doped carbon materials pyrolyzed from polyaniline/carbon nanocage composites[J]. Acta Chimica Sinica, 2015, 73(8): 793-798.
21	彭三, 郭慧林, 亢晓峰. 氮掺杂石墨烯的制备及其对氧还原反应的电催化性能[J]. 物理化学学报, 2014, 30(9): 1778-1786.
	PENG San, GUO Huilin, KANG Xiaofeng. Preparation of nitrogen-doped graphene and its electrocatalytic activity for oxygen reduction reaction[J]. Acta Physico-Chimica Sinica, 2014, 30(9): 1778-1786.

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