Internal medicine

Geology

Pathology

Nanotechnology

Organic chemistry

Surface energy

Reactivity (psychology)

Hydrogen

Ultimate tensile strength

Transition metal

Oceanography

Density functional theory

Catalysis

Philosophy

Computational chemistry

Nanoparticle

Chemical physics

Composite material

Chemistry

Metallurgy

Materials science

Alternative medicine

Stress (linguistics)

Substrate (aquarium)

Strain (injury)

Linguistics

Metal

Surface stress

Nanosheet

Biochemistry

Medicine

Science

Tuning surface strain is a powerful strategy for tailoring the reactivity of metal catalysts. Traditionally, surface strain is imposed by external stress from a heterogeneous substrate, but the effect is often obscured by interfacial reconstructions and nanocatalyst geometries. Here, we report on a strategy to resolve these problems by exploiting intrinsic surface stresses in two-dimensional transition metal nanosheets. Density functional theory calculations indicate that attractive interactions between surface atoms lead to tensile surface stresses that exert a pressure on the order of 105 atmospheres on the surface atoms and impart up to 10% compressive strain, with the exact magnitude inversely proportional to the nanosheet thickness. Atomic-level control of thickness thus enables generation and fine-tuning of intrinsic strain to optimize catalytic reactivity, which was confirmed experimentally on Pd(110) nanosheets for the oxygen reduction and hydrogen evolution reactions, with activity enhancements that were more than an order of magnitude greater than those of their nanoparticle counterparts.

Tunable intrinsic strain in two-dimensional transition metal electrocatalysts