Co and Pt Dual‐Single‐Atoms with Oxygen‐Coordinated Co–O–Pt Dimer Sites for Ultrahigh Photocatalytic Hydrogen Evolution Efficiency

Abstract

The platinum single‐atom‐catalyst is verified as a very successful route to approach the size limit of Pt catalysts, while how to further improve the catalytic efficiency of Pt is a fundamental scientific question and is challenging because the size issue of Pt is approached at the ultimate ceiling as single atoms. Here, a new route for further improving Pt catalytic efficiency by cobalt (Co) and Pt dual‐single‐atoms on titanium dioxide (TiO2) surfaces, which contains a fraction of nonbonding oxygen‐coordinated Co–O–Pt dimers, is reported. These Co–Pt dimer sites originate from loading high‐density Pt single‐atoms and Co single‐atoms, with them anchoring randomly on the TiO2 substrate. This dual‐single‐atom catalyst yields 13.4% dimer sites and exhibits an ultrahigh and stable photocatalytic activity with a rate of 43.467 mmol g−1 h−1 and external quantum efficiency of ≈83.4% at 365 nm. This activity far exceeds those of equal amounts of Pt single‐atom and typical Pt clustered catalysts by 1.92 and 1.64 times, respectively. The enhancement mechanism relies on the oxygen‐coordinated Co–O–Pt dimer coupling, which can mutually optimize the electronic states of both Pt and Co sites to weaken H* binding. Namely, the “mute” Co single‐atom is activated by Pt single‐atom and the activity of the Pt atom is further enhanced through the dimer interaction. This strategy of nonbonding interactive dimer sites and the oxygen‐mediated catalytic mechanisms provide emerging rich opportunities for greatly improving the catalytic efficiency and developing novel catalysts with creating new electronic states.

The Electronic Metal–Support Interaction Directing the Design of Single Atomic Site Catalysts: Achieving High Efficiency Towards Hydrogen Evolution

“…[22][23][24][25][26] Till now, many researches of SACs have been focused on the HER. [27][28][29][30][31][32][33] However, there is still some barrier on the way to apply the SACs in the practical hydrogen production. [34,35] To realize the practical use of the single atomic site catalysts, several problems are needed to be considered, such as regulating the catalytic efficiency of metallic center, regulating the conductivity of basement and so on.…”

Recent progress on polyvinyl alcohol-based materials for energy conversion

“…Hydrogen production by water electrolysis has been widely considered as an advanced approach to tackle the energy crisis and environmental pollution issues. [86][87][88] In spite of its great potential, industrial hydrogen production via water electrolysis has been severely hampered by the sluggish kinetics of water splitting. [89][90][91] To overcome the large energy barrier of water splitting, there is an urgent need to explore advanced electrocatalysts.…”

The Electronic Metal–Support Interaction Directing the Design of Single Atomic Site Catalysts: Achieving High Efficiency Towards Hydrogen Evolution

“…The arise of single atomic site catalysts (SACs) brings new hope to the hydrogen industry [22–26] . Till now, many researches of SACs have been focused on the HER [27–33] . However, there is still some barrier on the way to apply the SACs in the practical hydrogen production [34, 35] .…”