钴掺杂氧化铈纳米粒子电催化性能研究

doi:10.15541/jim20170516

摘要/Abstract

摘要：

氧化铈的电子导电性较低、氧空位数量少, 难以单独用作为电催化剂。但是掺杂过渡金属或非金属元素可以提高氧化铈的CO催化能力, 同时在氧化物中掺杂钴可有效提高材料的电催化能力, 因此本工作开展了对钴掺杂的氧化铈电催化性能的研究。采用均相沉淀法制备了钴掺杂的氧化铈纳米粒子, 电化学测试发现当钴掺杂比例为20mol%时, 氧化铈纳米粒子对氧气还原反应(ORR)和氧气析出反应(OER)的综合催化能力最强。经过10 h的长时间催化作用, ORR、OER过程中的电流密度分别下降了20%、5%左右, 远优于贵金属和未掺杂氧化铈纳米粒子催化剂, 显示出良好的催化稳定性。拉曼光谱、阻抗图及XPS谱图等的测试分析表明钴掺杂后材料的电荷转移阻抗降低(电子导电性的提高)、氧活性物种和氧空位增加是氧化铈催化性能提高的主要原因。本工作通过钴掺杂大幅度提高了氧化铈的电催化性能, 同时为其它离子导体作为双功能电催化剂的使用提供了借鉴。

关键词: 氧化铈, 掺杂, 电催化剂

Abstract:

It is very difficult for single ceria to be used as an electrocatalyst because of its relatively poor electron conductivity and rare number of oxygen vacancy. Recently, it has been studied in the field of CO catalysis by doping transition metallic or non-metallic elements to improve the catalytic ability of ceria, while recent research has demonstrated that many oxides containing cobalt display better electrocatalytic activity. In this study cobalt doped ceria nanoparticles were prepared by homogeneous precipitation method. The electrochemical tests show that the optimum doping molar ratio is 20mol% for ORR and OER catalytic effect. After 10 hours of catalysis, the current density of ORR and OER decrease by about 20% and 5%, respectively, far below the corresponding values when noble metal and undoped cerium oxide nanoparticles were used as catalysts, and it indicated that the prepared catalyst owns good catalytic stability. In addition, XPS and other tests show that the decrease of charge transfer impedance (the improvement of electronic conductivity), the increase of active oxygen species, and the increased oxygen vacancies after doping are main reasons for improved catalytic performance. Therefore, doping cobalt greatly enhanced electrocatalytic properties of ceria nanoparticles are greatly enhanced by doping cobalt, providing guidence for other ionic conductors employed as bifunctional electrocatalysts.

Key words: ceria oxide, doping, electrocatalyst

中图分类号:

TQ174

杨志宾, 岳彤联, 余向南, 吴苗苗. 钴掺杂氧化铈纳米粒子电催化性能研究[J]. 无机材料学报, 2018, 33(8): 845-853.

YANG Zhi-Bin, YUE Tong-Lian, YU Xiang-Nan, WU Miao-Miao. Electrocatalytic Activity of Cobalt Doped Ceria Nanoparticles[J]. Journal of Inorganic Materials, 2018, 33(8): 845-853.

图/表 11

图1 不同钴掺杂比例的氧化铈纳米粒子的XRD图谱

Fig. 1 XRD patterns of ceria nanoparticles with different doping ratio of cobalt(a) Whole range patterns; (b) Magnified patterns of the highest peak (111)

图2 (a)氧化铈纳米粒子的N2吸附-脱附曲线和(b)氧化铈纳米粒子的BJH孔径分布曲线

Fig. 2 (a) N2 adsorption-desorption isotherm of ceria nanoparticles and (b) BJH pore size distribution curve of ceria nanoparticles

图3 不同掺杂比例的氧化铈纳米粒子在1600 r/min下的ORR (a)和OER (b)极化曲线

Fig. 3 Polarization curves at 1600 r/min of different of ceria nanoparticles with different doping ratio(a) (ORR) and (b) (OER)

图4 (a)氧化铈纳米粒子和Pt/C在1600 r/min下的极化曲线(ORR); (b)氧化铈纳米粒子和RuO2在1600 r/min下的极化曲线(OER)

Fig. 4 Polarization curves at 1600 r/min of (a) ceria nanoparticles and Pt/C (ORR) and (b) ceria nanoparticles and RuO2 (OER)

图5 (a) RRDE模式下测得相应掺杂比例的氧化铈纳米粒子转移电子数; (b) 0.5 V时相应掺杂比例的氧化铈纳米粒子的K-L曲线

Fig. 5 (a) Corresponding transfer electron number of ceria nanoparticles with different doping amount in RRDE model, and (b) corresponding K-L plots of ceria nanoparticles with different doping ratio at 0.5 V

图6 (a)二种不同掺杂比例的氧化铈纳米粒子和Pt/C对应的计时电流曲线; (b)二种不同掺杂比例氧化铈纳米粒子和RuO2对应的计时电流曲线

Fig. 6 Current-time(I-t) chronoamperometric responses for ceria nanoparticles (a) at two different doping ratio and Pt/C, and (b) at two different doping ratio and RuO2

图7 (a)二种不同掺杂比例下对应氧化铈的ORR (a)和OER (b)的极化阻抗图谱

Fig. 7 (a) Corresponding ORR(a) and OER (b) electrochemical impedance spectra of Ceria at two different doping ratio

图8 二种不同钴掺杂比例下对应氧化铈的拉曼光谱图

Fig. 8 Corresponding Raman spectra of Ceria at two different doping ratio of Co

图9 二种不同掺杂比例下对应氧化铈的TEM和HRTEM照片

Fig. 9 Corresponding TEM and HRTEM images of Ceria at two different doping ratio(a, b) 0; (c, d) 20mol%

图10 Co掺杂比例为20mol%时CeO2的(a) XPS全谱和(b) Co2p的高分辨XPS图谱; 不同掺杂比例下CeO2中Ce3d (c)和O1s(d)的高分辨XPS图谱

Fig. 10 (a) XPS survey spectra and (b) high-resolution XPS spectra of Co2p of CeO2 doping with 20mol% Co; High-resolution XPS spectra of Ce3d (c) and O1s (d) of CeO2 with different doping ratio

表1 不同掺杂比例下对应的XPS结果

Table 1 Corresponding XPS results of different doping ratio

Sample	Content
Sample	O_α/at%	O_β/at%	O_δ/at%	O_γ/at%	O_β/O_α	[Ce³⁺/(Ce⁴⁺+Ce³⁺)]/%
0	48.5	29.2	10.4	11.8	0.60	20.1
20mol%	27.2	53.1	10.5	9.2	1.95	24.1

参考文献 35

[1]	JIE S, KEVIN J M, HUBERT A G,et al. A perovskite oxide optimized for oxygen evolution catalysis from molecular orbital principles.Science, 2011, 334(6061): 1383-1385.
[2]	JIN S, HUBERT A G, YABUUCHI N,et al. Design principles for oxygen-reduction activity on perovskite oxide catalysts for fuel cells and metal-air batteries.Nature Chemistry, 2011, 3(8): 647.
[3]	WU G, KARREN L M, JOHNSTON C M,et al. High-performance electrocatalysts for oxygen reduction derived from polyaniline, iron, and cobalt.Science, 2011, 332(6028): 443-447.
[4]	LEFÈVRE M, PROIETTI E, JAOUEN F,et al. Iron-based catalysts with improved oxygen reduction activity in polymer electrolyte fuel cells.Science, 2009, 324(5923): 71-74.
[5]	CAO Z X, DING Y M, WANG Z C,et al. Porous calcium manganese oxide: preparation and electrocatalytic activity of oxygen reduction reaction.Journal of Inorganic Materials, 2017, 32(5): 535-542.
[6]	HOU F, LI H, YANG Y,et al. Preparation and catalytic oxidation of CO with specific morphology and porous nano CeO2.Chemical Industry and Engineering Progress, 2017, 36(7): 2481-2487.
[7]	KE J, XIAO J W, ZHU W,et al. Dopant-induced modification of active site structure and surface bonding mode for high-performance nanocatalysts: CO oxidation on capping-free(110)-oriented CeO2: Ln (Ln=La-Lu) nanowires.Journal of the American Chemical Society, 2013, 135(40): 15191-15200.
[8]	XU B, ZHANG Q, YUAN S,et al. Synthesis and photocatalytic performance of yttrium-doped CeO2 with a porous broom-like hierarchical structure.Applied Catalysis B: Environmental, 2016, 183: 361-370.
[9]	HAO L, YU J, XU X,et al. Nitrogen-doped MoS2/carbon as highly oxygen-permeable and stable catalysts for oxygen reduction reaction in microbial fuel cells.Journal of Power Sources, 2017, 339: 68-79.
[10]	CHEN P, ZHOU T, XING L,et al. Atomically dispersed iron-nitrogen species as electrocatalysts for bifunctional oxygen evolution and reduction reactions.Angewandte Chemie International Edition, 2017, 56(2): 610-614.
[11]	ZHU Q L, XIA W, AKITA T,et al. Metal-organic framework-derived honeycomb-like open porous nanostructures as precious-metal-free catalysts for highly efficient oxygen electroreduction.Advanced Materials, 2016, 28(30): 6391-6398.
[12]	FENG J, LIANG Y G, WANG H L,et al. Engineering manganese oxide/nanocarbon hybrid materials for oxygen reduction electrocatalysis.Nano Research, 2012, 5(10): 718-725.
[13]	TAN Y M, XU C F, CHEN G X,et al. Facile synthesis of manganese-oxide-containing mesoporous nitrogen-doped carbon for efficient oxygen reduction.Advanced Functional Materials, 2012, 22(21): 4584-4591.
[14]	DONG C, LIU Z W, LIU Y J, ,et al.Modest oxygen-defective amorphous manganese-based nanoparticle mullite with superior overall electrocatalytic performance for oxygen reduction reaction. Small, 2017,13(16): 1603903-1-9.
[15]	LIANG Y Y, WANG H L, ZHOU J G,et al. Covalent hybrid of spinel manganese-cobalt oxide and graphene as advanced oxygen reduction electrocatalysts.Journal of the American Chemical Society, 2012, 134(7): 3517-3523.
[16]	PENDASHTEH A, PALAMA J, ANDERSON M,et al. NiCoMnO4 nanoparticles on N-doped graphene: highly efficient bifunctional electrocatalyst for oxygen reduction/evolution reactions.Applied Catalysis B: Environmental, 2017, 201: 241-252.
[17]	HARDIN W G, MEFFORD J T, SLANAC D A,et al. Tuning the electrocatalytic activity of perovskites through active site variation and support interactions.Chemistry of Materials, 2014, 26(11): 3368-3376.
[18]	HARDIN W G, SLANAC D A, WANG X,et al. Highly active, nonprecious metal perovskite electrocatalysts for bifunctional metal-air battery electrodes.The Journal of Physical Chemistry Letters, 2013, 4(8): 1254-1259.
[19]	HARTMANN P, BREZESINSKI T, SANN J,et al. Defect chemistry of oxide nanomaterials with high surface area: ordered mesoporous thin films of the oxygen storage catalyst CeO2-ZrO2.ACS Nano. 2013, 7(4): 2999-3013.
[20]	XU X M, SU C, ZHOU W, ,et al.3 Co-doping strategy for developing perovskite oxides as highly efficient electrocatalysts for oxygen evolution reaction.Advanced Science., 2016, 3(2): 1500187-1-6.
[21]	ZHU Y L, ZHOU W, SUNARSO J,et al. Phosphorus-doped perovskite oxide as highly efficient water oxidation electrocatalyst in alkaline solution.Advanced Functional Materials, 2016, 26(32): 5862-5872.
[22]	HE Y, ZHANG J F, HE G W,et al. Ultrathin Co3O4 nanofilm as an efficient bifunctional catalyst for oxygen evolution and reduction reaction in rechargeable zinc-air batteries.Nanoscale, 2017, 9(25): 8623-8630.
[23]	MENG Y T, SONG W Q, HUANG H,et al. Structure-property relationship of bifunctional MnO2 nanostructures: highly efficient, ultra-stable electrochemical water oxidation and oxygen reduction reaction catalysts identified in alkaline media.Journal of the American Chemical Society, 2014, 136(32): 11452-11464.
[24]	ZHAO X, FU Y, WANG J,et al. Ni-doped CoFe2O4 hollow nanospheres as efficient bi-functional catalysts.Electrochimica Acta, 2016, 201: 172-178.
[25]	XU B, ZHANG Q T, YUAN S S,et al. Synthesis and photocatalytic performance of yttrium-doped CeO2 with a hollow sphere structure.Catalysis Today, 2017, 281: 135-143.
[26]	LI H, MENG F, GONG J,et al. Structural, morphological and optical properties of shuttle-like CeO2 synthesized by a facile hydrothermal method.Journal of Alloys and Compounds, 2017, 722: 489-498.
[27]	DENG W, DAI Q G, LAO Y J,et al. Low temperature catalytic combustion of 1, 2-dichlorobenzene over CeO2-TiO2 mixed oxide catalysts.Applied Catalysis B: Environmental, 2016, 181: 848-861.
[28]	ZANG C J, ZHANG X S, HU S Y,et al. The role of exposed facets in the Fenton-like reactivity of CeO2 nanocrystal to the Orange II.Applied Catalysis B: Environmental, 2017, 216: 106-113.
[29]	FENG J, YE S H, XU H,et al. Design and synthesis of FeOOH/ CeO2 heterolayered nanotube electrocatalysts for the oxygen evolution reaction.Advanced Materials, 2016, 28(23): 4698-4703.
[30]	BECHE E, CHARVIN P, PERARNAU D,et al. Ce 3d XPS investigation of cerium oxides and mixed cerium oxide (C.xTiyOz). Surface and Interface Analysis, 2008, 40(3/4): 264-267.
[31]	LI L L, ZHANG L, MA K L,et al. Ultra-low loading of copper modified TiO2/CeO2 catalysts for low-temperature selective catalytic reduction of NO by NH3.Applied Catalysis B: Environmental, 2017, 207: 366-375.
[32]	LIANG F L, YU Y, ZHOU W,et al. Highly defective CeO2 as a promoter for efficient and stable water oxidation.Journal of Material Chemistry, 2015, 3(2): 634-640.
[33]	XU L, JIANG Q Q, XIAO Z H,et al. Plasma-engraved Co3O4 nanosheets with oxygen vacancies and high surface area for the oxygen evolution reaction.Angewandte Chemie International Edition, 2016, 55(17): 5277-5281.
[34]	ZHUANG L Z, GE L, YANG Y S, ,et al..Ultrathin iron-cobalt oxide nanosheets with abundant oxygen vacancies for the oxygen evolution reaction. Advanced Materials, 2017, 29(17): 1606793- 1-7.
[35]	WANG F, ZHANG L, XU L,et al. Low temperature CO oxidation and CH4 combustion over Co3O4 nanosheets.Fuel, 2017, 203: 419-429.