The Sb–Pt<sub>4</sub> “Inverted Pyramid”in D0<sub>23</sub>-Type Pt<sub>3</sub>Sb for Highly Efficient pH-UniversalHER Catalysis
We synthesized high-crystalline Pt<sub><i>x</i></sub>Sb<sub><i>y</i></sub> nanocrystals (NCs) via a hot-injection method (D0<sub>23</sub>-type tetragonal Pt<sub>3</sub>Sb, hexagonal PtSb, and cubic PtSb<sub>2</sub>). The Pt<sub>3</sub>Sb NCs exhibited isotropic microstrains (ε<sub>a</sub> = ε<sub>b</sub> = 0.022, ε<sub>c</sub> = 0.01) due to the presence of inverted-pyramid Sb–Pt<sub>4</sub> along the [001] axis, which enhanced the hydrogen evolution reaction (HER) performance. This special structure afforded Pt<sub>3</sub>Sb NCs with low overpotentials of 71 mV in 0.5 M H<sub>2</sub>SO<sub>4</sub> and 84 mV in 1.0 M KOH at 10 mA cm<sup>–2</sup>. Differential charge density calculations showed the Sb–Pt<sub>4</sub> expanded electron states of Pt sites, promoted conjugate delocalization of π bonds, and facilitated H adsorption, which was confirmed by the XPS and XAS characterizations. The higher d-band occupation near the Fermi level (d-band center, ε<sub>d</sub> = −2.34 eV) provided increased free electrons and boosted electrical conductivity. Comparative studies of hypothetical Pt<sub>3</sub>P and Pt<sub>3</sub>Bi crystallites highlighted crucial roles of Sb in the Sb–Pt<sub>4</sub> pyramid in Pt<sub>3</sub>Sb which significantly improved HER performance.
Publication Details
- Journal
- Figshare
- Published
- 2025-03-05
- DOI
- https://doi.org/10.1021/acs.nanolett.4c06664.s001
- Primary Topic
- Electrocatalysts for Energy Conversion
- Type
- article
- Field-Weighted Citation Impact
- 0.00