Size dependence of thermoelectric power of Au, Pd, Pt nanoclusters deposited onto HOPG surface

TL;DR

This study investigates how the thermoelectric power of Au, Pd, and Pt nanoclusters on HOPG varies with size, revealing material-dependent trends using scanning tunneling spectroscopy.

Contribution

It provides the first detailed analysis of size-dependent thermoelectric power in laser-deposited nanoclusters of different materials on HOPG.

Findings

Pd nanoclusters' thermoelectric power decreases with size

Au nanoclusters' thermoelectric power increases with size

Material-specific size dependence observed in thermoelectric properties

Abstract

The paper presents the study of tunnel current-voltage characteristics of Au, Pd and Pt nanoclusters deposited onto the highly oriented pyrolytic graphite (HOPG) surface by pulsed laser deposition. The analysis of tunnel current-voltage characteristics obtained by scanning tunneling spectroscopy (STS) allowed to recover the thermoelectric power value of nanoclusters. It was found that the value of thermoelectric power of pulsed laser deposited nanoclusters depends on nanocluster material and shows qualitative difference in size dependence for different materials of nanoclusters. Thus, thermoelectric power value of PLD Pd nanoclusters decreases with increasing of nanocluster size, while for Au nanoclusters this value increases. The analysis of the results are discussed.