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Tuned single atom coordination structures mediated by polarization force and sulfur anions for photovoltaics


Impeding high temperature sintering is challengeable for synthesis of carbon-supported single-atom catalysts (C-SACs), which requires high-cost precursor and strictly-controlled procedures. Herein, by virtue of the ultrastrong polarity of salt melts, sintering of metal atoms is effectively suppressed. Meanwhile, doping with inorganic sulfur anions not only produces sufficient anchoring sites to achieve high loading of atomically dispersed Co up to 13.85 wt.%, but also enables their electronic and geometric structures to be well tuned. When served as a cathode catalyst in dye-sensitized solar cells, the C-SAC with Co-N4-S2 moieties exhibits high activity towards the iodide reduction reaction (IRR), achieving a higher power conversion efficiency than that of conventional Pt counterpart. Density function theory (DFT) calculations revealed that the superior IRR activity was ascribed to the unique structure of Co-N4-S2 moieties with lower reaction barriers and moderate binding energy of iodine on the Co center, which was beneficial to I2 dissociation.


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This work was financially supported by the National Natural Science Foundation of China (Nos. 51773025 and 21701168) and the Natural Foundation of Liaoning Province (Materials Joint Foundation, No. 20180510027), Dalian Science and Technology Innovation Fund (No. 019J12GX032). We gratefully acknowledge the BL14W1 Beamline of Shanghai Synchrotron Radiation Facility (SSRF) in Shanghai, China and the 1W1B Beamline of Beijing Synchrotron Radiation Facility (BSRF) in Beijing, China for providing the beam time.

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Correspondence to Chao Zhu, Jiangwei Zhang or Yantao Shi.

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Jing, H., Zhao, Z., Zhang, C. et al. Tuned single atom coordination structures mediated by polarization force and sulfur anions for photovoltaics. Nano Res. 14, 4025–4032 (2021).

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  • inorganic sulfur ions
  • coordination structure regulating
  • anti-sintering
  • dye-sensitized solar cells