Computational chemistry

Chemistry

Materials science

Chromatography

Binding energy

Physics

Electrode

Physisorption

Work function

X-ray photoelectron spectroscopy

Atomic physics

Thermal stability

Chemisorption

Quantum mechanics

Electron

Organic chemistry

Activation energy

Physical chemistry

Thermal conduction

Conduction band

Analytical Chemistry (journal)

Adsorption

Density functional theory

Nuclear magnetic resonance

Composite material

npj 2D Materials and Applications

In this work we investigate the effects of ambient exposure on CVD grown PdSe 2 and correlate density functional theory calculations of various physisorption and chemisorption binding energies and band structures to the observed changes in the electrical transport. Pristine PdSe 2 is n-type due to intrinsic selenium vacancies, but shows increased p-type conduction and decreased n-type conduction as a function of ambient aging during which various aging mechanisms appear to be operative. Short term aging (&lt;160 h) is ascribed to an activated chemisorption of molecular O 2 at selenium vacancies; first-principles calculations suggest a ~0.85 eV activation energy and adsorption geometries with binding energies varying between 1.3–1.6 eV, in agreement with experimental results. Importantly, this chemisorption is reversible with a low temperature anneal. At long term aging (&gt;430 h), there is a total suppression of n-type conduction, which is attributed to a dissociative adsorption/reaction of the O 2 molecules...

Exploring the air stability of PdSe2 via electrical transport measurements and defect calculations