Excellent HER and OER Catalyzing Performance of Se-vacancies in Defects-engineering PtSe2: From Simulation to Experiment

TL;DR

This study combines theoretical simulations and experimental validation to demonstrate that Se vacancies in PtSe2 significantly enhance its catalytic performance for HER and OER, making it a promising bipolar catalyst for clean energy production.

Contribution

It is the first to systematically analyze Se vacancies in PtSe2 and experimentally confirm their superior catalytic activity for both HER and OER.

Findings

Se vacancies dramatically improve HER performance, surpassing Pt(111).

PtSe2 with Se vacancies is an effective OER catalyst.

Defective PtSe2 shows higher efficiency than pure Pt foils in water splitting.

Abstract

Facing with grave climate change and enormous energy demand, catalyzer gets more and more important due to its significant effect on reducing fossil fuels consumption. Hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) by water splitting are feasible ways to produce clean sustainable energy. Here we systematically explored atomic structures and related STM images of Se defects in PtSe2. The equilibrium fractions of vacancies under variable conditions were detailly predicted. Besides, we found the vacancies are highly kinetic stable, without recovering or aggregation. The Se vacancies in PtSe2 can dramatically enhance the HER performance, comparing with, even better than Pt(111). Beyond, we firstly revealed that PtSe2 monolayer with Se vacancies is also a good OER catalyst. The excellent bipolar catalysis of Se vacancies were further confirmed by experimental measurements. We produced defective PtSe2 by direct selenization of Pt foil at 773 K using a CVD process. Then we observed the HER and OER performance of defective PtSe2 is much highly efficient than Pt foils by a series of measurements. Our work with compelling theoretical and experimental studies indicates PtSe2 with Se defects is an ideal bipolar candidate for HER and OER.