Research Progress on Preparation Methods of Single-atom Catalysts

doi:10.15541/jim20240302

Abstract

Abstract:

Nowadays, we are facing increasingly serious energy and environmental problems, which urgently need more efficient chemical industry technologies to meet the requirements of low cost, high yield and sustainability. Developing efficient catalysts is of great significance for improving production efficiency, expanding economic benefits, optimizing energy structure, and ameliorating industrial structure. Single-atom catalysts (SACs), featuring unique properties arising from their single-atom dispersion on support surface, have demonstrated exceptional activity, selectivity and stability in energy catalysis, environmental catalysis and organic catalysis. Therefore, preparation methods and catalytic mechanisms of SACs have become a hot research topic on the international catalytic community. This review describes three strategies for preparing SACs: bottom-up synthesis, top-down synthesis and quantum dots cross-linking/self-assembly. Specifically, methods such as co-precipitation, immersion, atomic layer deposition, high-temperature atom thermal transfer, and high-temperature pyrolysis are presented in detail. These approaches precisely control the location and distribution of metal atoms, maximizing their utilization and catalytic efficiency. In addition, the challenges and development prospects faced by SACs related to stability, integrated control and industrial scalability are also summarized.

Key words: single-atom catalyst, top-down strategy, bottom-up strategy, synthesis, review

CLC Number:

TQ174

SUN Shujuan, ZHENG Nannan, PAN Haokun, MA Meng, CHEN Jun, HUANG Xiubing. Research Progress on Preparation Methods of Single-atom Catalysts[J]. Journal of Inorganic Materials, 2025, 40(2): 113-127.

Figures/Tables 11

Fig. 1 Synthesis strategies and applications for SACs

Fig. 2 Diagram of reverse water gas shift (rWGS) process[33]

Fig. 3 Research on OER mechanism for Ir1/Ni LDH-T and Ir1/Ni LDH-V[37] (a, b) Schematic structure models of Ir1/Ni LDH-T (a) and Ir1/Ni LDH-V (b) from top views; (c, d) Charge density differences of Ir atoms on Ir1/Ni LDH-T (c) and Ir1/Ni LDH-V (d) with yellow and cyan areas indicating electron accumulation and depletion, respectively; (e, f) Projected density of states (PDOS) in Ir1/Ni LDH-T (e) and Ir1/Ni LDH-V (f); (g) Free energy diagram of Ir1/Ni LDH-T and Ir1/Ni LDH-V with Ir as the active site; (h, i) Schematic OER pathways for Ir1/Ni LDH-T (h) and Ir1/Ni LDH-V (i) with pink, red, gray, and purple spheres representing H, O, Ni, and Ir atoms, respectively, and blue circles indicating reaction intermediates. Colorful figures are available on website

Fig. 4 High angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) images of (a-c) Pt SACs-ZIF-8-NC (30 s), (d-f) Pt subclusters-ZIF-8-NC (1 min), and (g-i) Pt NPs-ZIF-8-NC (5 min)[57] Colorful figures are available on website

Fig. 5 Construction strategy of Pd atomically dispersed catalysts (PdSA+C/g-C3N4)[68] Colorful figure is available on website

Fig. 6 Schematic preparation of SACs samples using frozen precursor solutions (experimental groups) and using liquid precursor solutions (control groups)[63]

Fig. 7 Diagram of Pt nanoparticle sintering[89]

Fig. 8 Schematic preparation of (a) Cu SACs/S−N[91] and (b) Bi-SACs-NS/C[92] Colorful figures are available on website

Fig. 9 Schematic illustration of Pt-LrEGO formation[96] Colorful figure is available on website

Fig. 10 Schematic diagrams of high-temperature pyrolysis preparative method[115⇓-117] (a) Preparation of Fe SACs/GO[115]; (b) N-doped carbon atomization of Pd NPs/TiO2[116]; (c) Single atomic catalyst using atomic Co site and polarization carrier[117]. Colorful figures are available on website

Fig. 11 Schematic illustration for synthesis processes of SACs[120] (a) Top-down synthesis strategy; (b) Bottom-up synthesis strategy; (c) Crosslinking and self-assembly based on graphene quantum dots (GQDs). Colorful figures are available on website

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