Recent advances in carbon-based catalysts for electrochemical reduction of carbon dioxide

doi:10.11949/0438-1157.20230174

Abstract

Abstract:

Converting carbon dioxide (CO₂) into high-energy fuel or high-value chemicals by electrochemical reduction technology is an effective way to enhance the added value of CO₂ utilization and alleviate the pressure of CO₂ emission, and is also one of the conversion and storage methods for green energy such as wind power, hydropower and solar energy, which is of great significance to “peak-clipping and valley-filling” of intermittent power. One of the keys to realize high-efficiency electrochemical reduction of CO₂ lies in the creation of high-performance electrocatalytic materials. In this paper, the research progress of carbon-based catalytic materials for electrochemical reduction of CO₂ is reviewed, and the structural characteristics of intrinsic defective carbon materials, doped carbon materials, carbon-based composites and monolithic carbon materials are discussed. On this basis, the challenges and future development of carbon-based catalytic materials for electrochemical reduction of CO₂ are prospected.

Key words: carbon-based catalyst, porous carbon, electrochemical reduction of carbon dioxide, single-atom catalyst, heteroatom doping

摘要：

利用电化学还原技术将二氧化碳（CO₂）转化为高能燃料或高值化学品是提升CO₂利用附加值、缓解CO₂排放压力的有效途径，也是风电、水电和太阳能等绿色能源的转化与存储方式之一，对间歇性电能“削峰填谷”意义重大。实现高效电化学还原CO₂的关键之一在于创制高性能的电催化材料。综述了碳基催化材料在电化学还原CO₂方面的研究进展，系统探讨了本征缺陷碳材料、掺杂碳材料、碳基复合材料和整体式碳材料的结构特点以及与电催化还原CO₂性能的构效关系，并在此基础之上，展望了碳基催化材料在电化学还原CO₂领域中的挑战和未来发展。

关键词: 碳基催化剂, 多孔炭, 电化学还原二氧化碳, 单原子催化剂, 杂原子掺杂

CLC Number:

O 6-1

Qiyu ZHANG, Lijun GAO, Yuhang SU, Xiaobo MA, Yicheng WANG, Yating ZHANG, Chao HU. Recent advances in carbon-based catalysts for electrochemical reduction of carbon dioxide[J]. CIESC Journal, 2023, 74(7): 2753-2772.

张琦钰, 高利军, 苏宇航, 马晓博, 王翊丞, 张亚婷, 胡超. 碳基催化材料在电化学还原二氧化碳中的研究进展[J]. 化工学报, 2023, 74(7): 2753-2772.

Figures/Tables 14

Fig.1 Timeline of the development of carbon-based electrocatalysts research in CO2RR[13-22]

Table 1 Cathodic products of electrochemical CO2RR

产物	k	m	n	$热力学电势 (v s S H E) / V$
CO	1	2	1	-0.52
HCOOH	1	2	0	-0.61
HCHO	1	4	1	-0.51
CH₃OH	1	6	1	0.02
CH₄	1	8	2	0.17
C₂H₄	2	12	4	0.08
CH₃CH₂OH	2	12	3	0.09

Table 1 Cathodic products of electrochemical CO2RR

产物	k	m	n	$热力学电势 (v s S H E) / V$
CO	1	2	1	-0.52
HCOOH	1	2	0	-0.61
HCHO	1	4	1	-0.51
CH₃OH	1	6	1	0.02
CH₄	1	8	2	0.17
C₂H₄	2	12	4	0.08
CH₃CH₂OH	2	12	3	0.09

Fig.2 Reaction pathways of electrochemical CO2RR in aqueous solution and the corresponding products

Fig.3 Schematic diagrams of the structures and DFT calculations for CO2RR activities of four different defect types[18]

Fig.4 Schematic representation of heteroatom doping in carbon matrix and DFT calculation based on different nitrogen sites[46]

Fig.5 Electron micrographs of F-doped carbon catalysts, and their doping models and DFT theoretical calculation for different sites[53]

Table 2 Performance comparisons of non-metallic heteroatom-doped carbon materials in electrochemical CO2RR

催化剂	电解液	FE/%	主要产物	过电势/V	活性中心
FC^[53]	0.1 mol·L^-1 KHCO₃	89.6	CO	0.51	氟原子和碳原子
NDC^[41]	0.5 mol·L^-1 NaHCO₃	83.7	CO	0.71	吡啶氮原子
N/C-Cl-1100^[42]	0.1 mol·L^-1 KHCO₃	99.5	CO	0.40	石墨氮原子
CPSN^[44]	0.1 mol·L^-1 KHCO₃	11.3	CO	0.88	碳原子
BND^[45]	0.1 mol·L^-1 NaHCO₃	93.2	CH₃CH₂OH	0.90	硼原子和氮原子
NCNTs^[47]	0.1 mol·L^-1 KHCO₃	约80	CO	—	吡啶氮原子和石墨氮原子
NCNTs^[48]	0.1 mol·L^-1 KHCO₃	约80	CO	0.26	吡啶氮原子和石墨氮原子
NG^[21]	0.1 mol·L^-1 KHCO₃	约85	CO	0.47	吡啶氮原子
NG-T^[50]	0.5 mol·L^-1 KHCO₃	95.0	CO	0.62	碳原子
c-NC^[52]	0.1 mol·L^-1 KHCO₃	77.0	CH₃CH₂OH	0.63	吡啶氮原子和吡咯氮原子

Fig.6 Structural characterization of single atom Ni doped graphene and its performance and structural evolution in CO2RR process [59]

Fig.7 Structural model, characterization, TOFs and free energy of dual-metal active sites catalysts[19, 86]

Table 3 Performance comparisons of single-atom metal-doped carbon materials in electrochemical CO2RR

催化剂	电解液	FE/%	电流密度/(mA·cm^–2)	主要产物	过电势/V	活性中心
Ni²⁺@NG^[57]	0.5 mol·L^-1 KHCO₃	92	10.2	CO	0.58	Ni-N₄
NiSA/NP^[88]	0.5 mol·L^-1 NaHCO₃	99	131	CO	0.7	Ni-N₃
P-NiSA/PCFM^[16]	0.5 mol·L^-1 KHCO₃	95	56.1	CO	0.6	Ni-N₄
Ni-N-C^[89]	0.1 mol·L^-1 KHCO₃	97.9	12.6	CO	0.67	Ni-N _x
NC-CNTs (Ni)^[90]	0.1 mol·L^-1 KHCO₃	90	10	CO	0.9	Ni-N₃
A-Ni-NSG^[59]	0.5 mol·L^-1 KHCO₃	97	22	CO	0.4	Ni-N₄
NiSA-N-CNTs^[91]	0.5 mol·L^-1 KHCO₃	91.3	23.5	CO	0.6	Ni-N₄
Ni-N₃-V SAC^[77]	0.5 mol·L^-1 KHCO₃	94	65	CO	0.7	Ni-N₃
C-Zn _x Ni _y ZIF-8^[84]	1 mol·L^-1 KHCO₃	97.8	71.5	CO	0.53	Ni-N₂
Ni-N₄-C^[92]	0.1 mol·L^-1 KHCO₃	99	36.2	CO	0.71	Ni-N₄
Ni-NG^[58]	0.5 mol·L^-1 KHCO₃	95	11	CO	0.62	Ni-N _x
Ni-NCB^[17]	0.5 mol·L^-1 KHCO₃	99	22	CO	0.58	Ni-N _x
FeN₄Cl/NC^[78]	0.5 mol·L^-1 KHCO₃	90.5	10.8	CO	0.49	Fe-N₄Cl
Fe/NG-750^[93]	0.1 mol·L^-1 KHCO₃	80	2.63	CO	0.5	Fe-N₄
Fe-NC-S^[94]	0.5 mol·L^-1 KHCO₃	93	4	CO	0.29	Fe-N₄
Cu–N₂/GN^[76]	0.1 mol·L^-1 KHCO₃	81	2.1	CO	0.4	Cu-N₂
Cu SAs/GDY^[95]	0.1 mol·L^-1 KHCO₃	66	24	CH₄	1.47	Cu-C
In SAs/NC^[70]	0.5 mol·L^-1 KHCO₃	96	8.87	HCOOH	0.53	In-N₄
Pd-NC^[64]	0.5 mol·L^-1 NaHCO₃	55	2.2	CO	0.4	Pd-N₄
Single-atom Sn ^δ^+[65]	0.25 mol·L^-1 KHCO₃	74.3	11.7	HCOOH	1.24	Sn-N₂
(Cl, N)-Mn/G^[69]	0.5 mol·L^-1 KHCO₃	97	10	CO	0.49	Mn-N₄Cl
Co₁-N₄^[96]	0.1 mol·L^-1 KHCO₃	82	15.8	CO	0.7	Co-N₄
Zn–N–G^[63]	0.5 mol·L^-1 KHCO₃	91	11.2	CO	0.39	Zn-N₄
Cu/Pc-C^[97]	0.5 mol·L^-1 KCl	25	2.8	C₂H₄	1.68	Cu-N₄
Dual Cu SAC^[87]	0.1 mol·L^-1 KHCO₃	91	＞90	C₂₊	—	Cu-Cu-N₆

Fig.8 Engineering surface amine modifiers of ultrasmall gold nanoparticles supported on reduced graphene oxide electrocatalyst[109]

Fig.9 Hydrophobic carbon nanofibers supported bismuth oxide nanosheets as electrocatalysts[121]

Fig.10 Structural modeling, theoretical calculations and stability test of rGO- and CNTs-loaded cobalt phthalocyanine molecular catalysts for CO2RR [133]

Fig.11 Preparation process, photos and stability test in a flow cell of carbon fiber membrane material loaded with single atom Ni[16]

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