Electrochemical CO₂ reduction reaction (CO₂RR) offers a sustainable pathway to convert renewable electricity into high-value chemicals. Currently, researchers worldwide have made significant efforts in developing CO₂RR catalysts. However, existing catalysts still struggle to achieve high selectivity and stability under industrial-level current densities (>200 mA cm⁻⟡), severely limiting their practical application.
Studies have shown that tuning the local microenvironment is an effective strategy for optimizing CO₂RR. In the CO₂RR-relevant local microenvironment, hydrogen-bond networks dominated by H₂O play a critical role in the rate of proton transfer, a key step in CO₂RR. While most previous studies have focused on optimizing the hydrogen-bond network through electrolyte engineering, the influence of the intrinsic catalyst structure on the local microenvironment has often been overlooked.
To address this, Professor Guo Shaojun’s team at Peking University reported a novel turing-structured topological catalyst that significantly enhances both selectivity and stability for CO₂ electroreduction at industrial-level current densities. This work, titled “Industrial-level CO₂ to Formate Conversion on Turing-Structured Electrocatalysts”, was published in Nature Synthesis.
The study introduces a generalizable method to fabricate defect-rich, porous Turing-structured SnSb oxide nanosheet catalysts (Figures 1 & 2). Atomic force microscopy characterization (Figure 2a) revealed the ultrathin nature of the Turing-structured SnSb oxide nanosheets. Electron paramagnetic resonance (Figure 2b) and extended X-ray absorption fine structure analyses (Figure 2f) confirmed that the turing-structured catalysts possess abundant defects and low coordination sites.
Figure 1. Microscopic Structure of the Turing-Structured SnSb Oxide Catalyst.
Figure 2. Detailed Structural Characterization of the Turing-Structured SnSb Oxide Catalyst.
Performance studies of CO₂ electroreduction devices demonstrated that the Turing-structured SnSb oxide nanosheets achieved highly efficient CO₂-to-formate conversion at industrial-level current densities (1000 mA cm⁻⟡) in both alkaline and acidic flow cells (Figure 3a), with formate Faradaic efficiency reaching 92%. In a membrane electrode assembly (MEA) electrolyzer, the Turing-structured SnSb oxide nanosheets operated stably for 200 hours at a low cell voltage of 3.3 V under industrial-level current densities (2500 mA, 500 mA cm⁻⟡), achieving an overall energy efficiency of 39.1% and a formate production rate of 8.0 mmol h⁻¹ cm⁻⟡ (Figure 3d). These results surpass the highest reported performance of CO₂-to-formate electrolyzers in the literature (Figure 3e).
Figure 3. Performance of the CO₂-to-Formate Electrolyzer.
In situ ATR-FTIR studies (Figure 4) revealed that the 4-HB/2-HB ratio of interfacial water on the Turing-structured catalysts (3.10 for Turing SnO₂ and 1.60 for Turing Sb₀.₁Sn₀.₉O₂) is significantly higher than that of non-Turing structures (0.26 for SnO₂). This indicates that the topological features of the Turing structure effectively strengthen hydrogen-bond network interactions at the electrode–electrolyte interface and demonstrate that the orientation of interfacial water is strongly modulated by the Turing architecture.
Figure 4. In Situ Spectroscopic Characterization of Interfacial Water Microenvironment Regulation.
Combining experimental characterizations and theoretical calculations (Figure 5), the study confirmed that precise tuning of the surface oxophilicity of Turing catalysts can reorient interfacial water molecules (4-HB/2-HB ratio from 0.26 to 3.10), thereby maintaining high Faradaic efficiency (>90%) for formate electrosynthesis under industrial-level current densities (300–1000 mA cm⁻⟡). By establishing a volcano-type structure–activity relationship between intrinsic catalytic activity and the oxophilicity of the Turing structure, the researchers identified guidelines for optimizing active site design. This work highlights the potential of topologically mediated interfacial water microenvironment regulation in industrial CO₂-to-formate electrosynthesis and opens new avenues for the industrial electrosynthesis of other high-value feedstocks.
Figure 5. Correlation Between Theoretical Descriptors and Catalytic Performance.
Postdoctoral researchers Na Ye and Kai Wang, along with PhD student Yingjun Tan, are co-first authors of the paper, and Professor Shaojun Guo serves as the sole corresponding author. This work was supported by Science and Technology Innovation Project of Laoshan Laboratory, the National Science Fund for Distinguished Young Scholars, the Beijing Natural Science Foundation, and the Postdoctoral Science Foundation.
DOI：https://doi.org/10.1038/s44160-025-00769-9
