Carbon-Defect-Driven Electroless Deposition of Pt Atomic Clusters for Highly Efficient Hydrogen Evolution

Abstract

Pt atomic clusters (Pt-ACs) display outstanding electrocatalytic performance because of their unique electronic structure with a large number of highly exposed surface atoms. However, the small size and large specific surface area intrinsically associated with ACs pose challenges in the synthesis and stabilization of Pt-ACs without agglomeration. Herein, we report a novel one-step carbon-defect-driven electroless deposition method to produce ultrasmall but well-defined and stable Pt-ACs supported by defective graphene (Pt-AC/DG) structures. A theoretical simulation clearly revealed that the defective regions with a lower work function and hence a higher reducing capacity compared to those of normal hexagonal sites triggered the reduction of Pt ions preferentially at the defect sites. Moreover, the strong binding energy between Pt and carbon defects effectively restricted the migration of spontaneously reduced Pt atoms to immobilize/stabilize the resultant Pt-ACs. Electrochemical analyses demonstrated the high performance of Pt-ACs in catalyzing the hydrogen evolution reaction, showing a greatly enhanced mass activity, a high Pt utilization efficiency, and excellent stability compared with commercial Pt/C catalysts. The integration of proton exchange membrane water electrolysis with Pt-AC/DG as a cathode exhibited an excellent hydrogen generation activity and extraordinary stability (during 200 h of electrolysis) with a greatly reduced Pt usage compared with commercial Pt/C catalysts.

RuRh Bimetallene Nanoring as High‐efficiency pH‐Universal Catalyst for Hydrogen Evolution Reaction

“…[ 2 ] Platinum (Pt) is the most widely used catalyst nowadays in a pH‐universal range; however, its high‐cost and scarcity has driven researchers to explore the cost‐effective noble metal HER catalysts to replace Pt without sacrificing the HER activity in a wide pH range. [ 3,4 ] One of the efficient strategies is to increase active catalytic centers in the Pt‐free noble metal catalysts, such as alloying, modifying the crystal phase, introducing unique nanostructures (nanoframes, nanosheets/nanowires, porous/hybridization nanomaterials, etc. ), interface modulation, and defect engineering.…”

Multiatom Catalysts for Energy‐Related Electrocatalysis

“…These defects (i.e., vacancies, step edges, pentagons, and heptagons in the graphitic structure) can not only trap metal precursors and stabilized metal atoms during post‐treatment but also contribute to enhanced catalytic performance through the formation of unique atomic structure. [ 35–43 ] For example, Zhang et al. reported an atomic Co‐Pt/N‐doped‐carbon catalyst (A‐CoPt‐NC) by utilizing the defects on the surface of the carbon capsules to uniformly trap Co‐Pt active sites ( Figure a).…”

“…[ 44 ] Theoretical calculation suggests the defective regions have a lower work function and hence higher reducing capacity, triggering the preferential reduction of Pt ions at the defect sites during the electroless deposition. [ 35 ] The strong binding energy between carbon defects and the spontaneously reduced Pt atoms results in the formation of ultrasmall Pt clusters (≈0.8 nm) (Figure 3c).…”

Synthesis Strategies, Catalytic Applications, and Performance Regulation of Single‐Atom Catalysts

“…[ 81,82 ] They occur at the cathode and anode of a water‐splitting electrolyzer, where there is an urgent need to completely replace and/or lower the noble metal catalysts loading, particularly the Pt group metals (e.g., Pt, Pd, Ru, Ir, and Rh) located close to the peak of the volcano curve and demonstrated prominent performance toward HER and OER. [ 83,84 ] Among these reported catalysts, SACs have been regarded as the most efficient one that exposed each atom and have nearly 100% atomic utilization. [ 68,85 ]…”