CO<sub>2</sub>电还原生成甲酸盐机理及催化剂研究

赵萍萍; 廉红蕾

doi:10.19906/j.cnki.JFCT.2023048

CO₂电还原生成甲酸盐机理及催化剂研究

doi: 10.19906/j.cnki.JFCT.2023048

赵萍萍^{1, 2,},
廉红蕾^{1, 2, ,}

1.
郑州大学化工学院先进功能材料制造教育部工程研究中心, 河南郑州 450000
2.
炼焦煤资源绿色开发全国重点实验室, 河南郑州 450000

详细信息

通讯作者:
Tel: 13663002080, E-mail: hongleilian@zzu.edu.cn

中图分类号: O643.3
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- 文章访问数: 133
- HTML全文浏览量: 51
- PDF下载量: 40
- 被引次数: 0
出版历程
- 收稿日期: 2023-04-25
- 修回日期: 2023-06-05
- 录用日期: 2023-06-06
- 网络出版日期: 2023-07-08
- 刊出日期: 2023-11-13

Research on mechanism and catalysts of CO₂ electroreduction to formate

ZHAO Ping-ping^{1, 2
,},
LIAN Hong-lei^{1, 2
, ,}

1.
Engineering Research Center of Advanced Functional Material Manufacturing of Ministry of Education, School of Chemical Engineering, Zhengzhou University, Zhengzhou 450000, China
2.
National Key Laboratory of Coking Coal Green Process Research, Zhengzhou 450000, China

摘要

摘要: 本工作综述了近五年来CO₂电催化还原生成甲酸盐领域取得的最新进展。介绍了CO₂电还原生成甲酸盐的反应机理，以及该过程所使用的催化剂的类型，包括金属催化剂、原子分散催化剂、金属氧化物催化剂、炭材料及复合材料催化剂。从催化剂、电解液、反应气氛和电解池等多角度详细分析了影响产物选择性、催化活性和稳定性的主要因素。针对目前CO₂电还原生成甲酸盐研究现状，提出对纳米材料和复合材料进行创新，借助原位表征技术探究活性位点及反应路径，并用于指导高效催化剂的设计与合成，改进电化学反应器组件以提高催化效率等问题可以作为未来的研究重点和发展方向。
- CO₂电还原 /
- 反应机理 /
- 催化剂 /
- 甲酸盐
Abstract: This paper reviews the latest progress in the field of CO₂ electrocatalytic reduction to formate in the past five years. The reaction mechanism of CO₂ electroreduction to formate and the types of catalysts used in this process are introduced, including metal catalysts, atomic dispersion catalysts, metal oxide catalysts, carbon materials, and composite material catalysts. The main factors affecting product selectivity, catalytic activity and stability are analyzed in detail from the perspectives of catalyst, electrolyte, reaction atmosphere and electrolytic cell. In view of the current research status of carbon dioxide electroreduction to formate, it is proposed to innovate on nanomaterials and composites, explore the active site and reaction path with the help of in-situ characterization technology, and guide the design and synthesis of efficient catalysts, improve the electrochemical reactor module to improve the catalytic efficiency and other issues can be regarded as the future research focus and development direction.
- CO₂ electroreduction /
- reaction mechanism /
- catalyst /
- formate

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FIG. 2763. FIG. 2763.

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图 1 CO₂-ECR生成甲酸盐、CO和其他产物的可能反应路径^[14]

Figure 1 Possible reaction pathways for CO₂-ECR to formate, CO and other products^[14] (with permission from Wiley publication)

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图 2 (a)Bi、Bi₂O₃和Bi₂O₃衍生物上CO₂电还原为甲酸自由能；(b)Bi和Bi₂O₃上CO₂还原过程示意图^[23]

Figure 2 (a) The free energy calculation of CO₂ conversion to formate over Bi, Bi₂O₃, and Bi₂O₃ derivative; (b) reduction process of CO₂ over Bi and Bi₂O₃^[23] (with permission from ACS publication)

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图 3 (a) PdCuAuAgBiIn HEAAs和(b) PdCuAuAgBiIn HEAPs的原位衰减全反射红外吸收光谱谱图^[27]

Figure 3 In-situ attenuated total reflectance infrared absorption spectroscopy of (a) PdCuAuAgBiIn HEAAs and (b) PdCuAuAgBiIn HEAPs^[27] (with permission from Wiley publication)

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图 4 (a)原位拉曼测试装置示意图；在0.5 mol/L KHCO₃电解液中，CO₂鼓泡条件下，BiCuSeO催化剂的原位拉曼光谱谱图：(b)不同还原电位，((c)−(d))不同反应时间^[28]

Figure 4 (a) Schematic illustration of the in situ Raman measurement device during the CO₂-ECR; (b) potential- dependent and ((c)−(d)) time-dependent in situ Raman spectra of BiCuSeO catalysts in 0.5 mol/L KHCO₃ solution under CO₂ bubbling^[28] (with permission from Nature publication)

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图 5 (a)基于Poisson-Nernst-Planck模拟得到的H⁺离子浓度C_{H +}与外亥姆霍兹面之间距离的关系；(b)不同K⁺浓度下的产物选择性；(c)在没有或存在K⁺的情况下，CO₂-ECR生成HCOOH的吉布斯自由能^[37]

Figure 5 (a) The ions concentration C_{H +} as function of distance from the outer Helmholtz plane (OHP) based Poisson-Nernst-Planck simulations; (b) product selectivity at different K⁺ concentrations; (c) Gibbs free energy diagram of CO₂-ECR to HCOOH in the absence or presence of K⁺ cations^[37] (with permission from ACS publication)

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图 6 Sn-Bi界面结构催化剂的(a)扫描电镜照片；(b)透射电镜照片；不同样品（Sn-Bi界面，Sn-Bi合金，电沉积ED-Bi，水热法SnO_x，电沉积ED-Sn）的(c)FE_HCOOH和(d)PCD_HCOOH^[41]

Figure 6 (a) SEM image and (b) TEM image of Sn-Bi interfacial catalyst; (c) FE_HCOOH and (d) PCD_HCOOH over various samples (Sn-Bi interface, Sn-Bi alloy, electrodeposition ED-Bi, hydrothermal SnO_x and electrodeposition ED-Sn)^[41] (with permission from Nature publication)

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图 7 (a)Pd 3d精细XPS光谱谱图；(b)PdCuAuAgBiIn HEAAs的伏安曲线；(c)PdCuAuAgBiIn HEAAs和(d)Pd金属气凝胶（Pd MAs）在不同电位下各种产物的法拉第效率^[27]

Figure 7 (a) Pd 3d fine XPS spectra; (b) CO stripping curve of PdCuAuAgBiIn HEAAs; Reduction potential dependent FEs measured on (c) PdCuAuAgBiIn HEAAs and (d) Pd MAs^[27] (with permission from Wiley publication)

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图 8 (a)*OCHO和*COOH在In-N-C表面的稳定吸附的几何结构；(b)在In-N-C、In(101)、In(110)和In(112)表面CO₂-ECR自由能^[51]

Figure 8 (a) Stable adsorption geometry of *OCHO and *COOH on the surface of In-N-C; (b) free energy diagram on the surface of In-N-C, In(101), In(110) and In(112) under CO₂-ECR^[51] (with permission from ACS publication)

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图 9 NW-SnO₂的(a)低分辨率和((b)、(c))高分辨率透射电镜照片^[60]

Figure 9 (a) Low resolution TEM images and ((b), (c)) high resolution TEM images of NW-SnO₂^[60] (with permission from Elsevier publication)

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图 10 在含0.5 mol/L KHCO₃电解液的H型电解池中，Bi₂O₃@C/HB、Bi₂O₃@C/HL、C/HB、C/HL的(a)线性扫描伏安曲线，(b)甲酸盐法拉第效率，(c)甲酸盐部分电流密度；在含1 mol/L KOH电解液的流动池中，Bi₂O₃@C/HB和Bi₂O₃@C/HB的(d)线性扫描伏安曲线，(e)甲酸盐法拉第效率，(f)甲酸盐部分电流密度^[74]

Figure 10 (a) Linear sweep voltammetry curve, (b) FE_formate, (c) j_formate of Bi₂O₃@C/HB, Bi₂O₃@C/HL, C/HB, C/HL in a H-cell containing 0.5 mol/L KHCO₃ electrolyte, (d) Linear sweep voltammetry curve, (e) FE_formate, (f) j_formate of Bi₂O₃@C/HB, Bi₂O₃@C/HL in a flow cell containing 1 mol/L KOH electrolyte^[74] (with permission from ACS publication)

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图 11 SnCu-CNS的(a)扫描电镜照片；(b)透射电镜照片^[86]

Figure 11 (a) SEM and (b) TEM images of SnCu-CNS^[86] (with permission from Wiley publication)

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图 12 在−1.6 V vs. RHE电位下对(a)BiOCl_0.5Br_0.5，(b)BiOCl_0.5I_0.5，(c)BiOBr_0.5I_0.5进行恒电位电解^[89]

Figure 12 Controlled potential electrolysis on (a) BiOCl_0.5Br_0.5, (b) BiOCl_0.5I_0.5, (c) BiOBr_0.5I_0.5 at −1.6 V vs. RHE^[89] (with permission from Elsevier publication)

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图 13 Bi(012)和Bi(003)晶面上OCHO*形成的自由能^[91]

Figure 13 Free energy for OCHO* generation on (012) and (003) facet of Bi^[91] (with permission from Elsevier publication)

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图 14 (a)电解质类型和阳离子尺寸对电流密度和FE_HCOOH的影响 0.1 mol/L的MHCO₃(M= Li⁺、Na⁺、K⁺、Rb⁺、Cs⁺)电解液，−1.4 V vs. RHE电位，SnO₂/C电极；(b)0.1 mol/L的NaX和KX(X = ${\rm{HCO}}_3^- $、Cl⁻、Br⁻ and I⁻)电解液中，−1.4 V vs. RHE电位下，SnO₂/C电极上得到的电流密度和FE_HCOOH^[93]

Figure 14 (a) Current density and FE_HCOOH as functions of electrolyte type and the cation size, measured using an SnO₂/C electrode at −1.4 V in 0.1 mol/L MHCO₃ (M = Li⁺, Na⁺, K⁺, Rb⁺, Cs⁺) electrolytes; (b) current density and FE_HCOOH at the SnO₂/C electrode at −1.4 V in 0.1 mol/L NaX and KX (X = ${\rm{HCO}}_3^- $, Cl⁻, Br⁻ and I⁻), respectively^[93] (with permission form Elsevier publication)

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图 15 在1 mol/L KHCO₃中100 mA/cm²的恒定电流密度下，在(a)Ag，(b)Sn和(c)Cu催化剂上的CO₂ + SO₂催化性能^[97]

Figure 15 Performance of CO₂ + SO₂ electrolysis over (a) Ag, (b) Sn and (c) Cu catalysts at constant current density of 100 mA/cm² in 1 mol/L KHCO₃^[97] (with permission from ACS publication)

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表 1 不同催化剂电还原CO₂生成甲酸盐的性能

Table 1 Performance of electroreduction CO₂ towards formate over various catalysts

Catalyst	Potential (V vs. RHE)	FE_HCOO⁻/%	J_HCOO⁻/(mA·cm⁻²)	Cell type	Electrolyte	Reference
PdCuAuAgBiIn HEAAs	−1.1	98.1	−	H-cell	0.1 mol/L KHCO₃	[27]
hp-In	−1.2	90	67.5	H-cell	0.1 mol/L KHCO₃	[33]
Bi NS	−1.23	92.2	237.1	flow cell	0.5 mol/L H₂SO₄(K⁺)	[37]
CuSn	−1.4	87.3	140.6	H-cell	0.5 mol/L KHCO₃	[40]
Sn-Bi	−0.84	96.4	−	H-cell	0.5 mol/L KHCO₃	[41]
Sn SA/ZnO	−1.2	80	−	flow cell	0.5 mol/L KHCO₃	[50]
In-N-C	−0.79	80	6.8	H-cell	0.5 mol/L KHCO₃	[51]
BiO_n	−	90	500	MEA	0.1 mol/L KOH	[58]
Bi₂O₃-A	−1.2	91	22	H-cell	0.5 mol/L KHCO₃	[59]
NW-SnO₂	−1.0	87.4	22	H-cell	0.5 mol/L KHCO₃	[60]
BDD	−	90	2	flow cell	0.5 mol/L KCl	[67]
Bi-HTC/OCNTs	−1.01	94	17.8	H-cell	0.5 mol/L KHCO₃	[72]
In₂S₃-rGO	−1.2	91	−	H-cell	0.1 mol/L KHCO₃	[73]
Bi₂O₃@C/HB	−0.7	93.8	−	H-cell	0.5 mol/L KHCO₃	[74]
	−1.5	−	285	flow cell	1 mol/L KOH
Bi₂O₃@C	−1.1	93	208	flow cell	1 mol/L KOH	[76]
In₂O₃@C	−1.1	94	−	flow cell	1 mol/L KOH	[77]
Bi₂S₃	−0.95	93	1900	flow cell	1 mol/L KOH	[84]
CuS/SnO₂-S	−0.8	84.9	18.8	H-cell	0.5 mol/L KHCO₃	[85]
SnCu-CNS	−0.9	95.1	−	H-cell	0.1 mol/L KHCO₃	[86]

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