KPFM visualisation of the Schottky barrier at the interface between gold nanoparticles and silicon

Abstract

Gold nanoparticles (AuNPs) deposited on a doped silicon substrate induce a local band bending and a local accumulation of positive charges in the semiconductor. Unlike the case of planar gold-silicon...

Enhanced Photocatalytic Activity of Surface‐Modified TiO2 with Bimetallic AuPd Nanoalloys for Hydrogen Generation

“…[66] The Schottky barrier is formed due to the interface contact between Au and Pd NPs (metallic system) and TiO 2 (semiconductor system). [67] The Schottky contact creates an internal electric field helping the electron-hole transfer and inhibiting the recombination process, which is confirmed by TRMC results (Figure 4a,b).…”

“…Smaller NPs have higher work function than larger NPs improving the Schottky barrier effect and therefore reducing the charge‐carrier recombination. [ 14,66,67 ] TRMC results confirm that the AuPd nanoalloys are efficient in electron scavenging reducing charge‐carrier recombinations and raising the photocatalytic activity under UV light excitation (Figure 4c). The decay increases when the TiO 2 surface is modified with AuPd nanoalloys.…”

Boosted Surface Charge in a Heterostructural Titanate Perovskite Cathode for a Highly Efficient CO2 Solid Oxide Electrolyzer

“…23,24 However, only very recently, the complex system with metallic nanoparticles deposited on the oxide support was studied via KPFM. 25,26 In this method, the precursor is introduced on the surface of metal−oxide support and the metallic particles are formed after additional treatment. 27,28 Generally, the metallic particles usually adhere to the support's surface and the contact between metallic particles and their metal−oxide support would be weak.…”

“…On the other hand, the Schottky effect was proposed to describe the metal contact with a semiconducting metal oxide and this effect could cause a polarization at the metal–metal oxide interface by the electron transfer from the substrate to the metallic nanoparticles or vice versa. , This behavior is relative to the different positions of the Fermi level, which is dependent on the metal particle as donor or acceptor defects in the support. − However, the main challenge in metallic catalyst studies is measuring the surface charge information on the electronics properties at the nanoscale. A majority of applications comprise the use of catalysts, and Kelvin probe force microscopy (KPFM) is one of the powerful techniques to provide the surface charge states in heterostructures via measuring the contact potential or work function (WF). , However, only very recently, the complex system with metallic nanoparticles deposited on the oxide support was studied via KPFM. , In this method, the precursor is introduced on the surface of metal–oxide support and the metallic particles are formed after additional treatment. , Generally, the metallic particles usually adhere to the support’s surface and the contact between metallic particles and their metal–oxide support would be weak. , Furthermore, the unreacted substances or organic monolayer around the metallic particles will hinder the carrier transfer resulting in poor catalytic activity. It could be obtained the surface physical property that does not really reflect from the metallic nanoparticle …”