Effect of Silver Nanoclusters on Physical and Electrical Properties of Cerium Oxide Thin Film

Abstract

An in situ X-ray photoelectron spectroscopy (XPS) investigation has revealed that silver metal clusters (Ag-NCs) can enhance the redox property of cerium oxide (CeO2) at relatively lower temperatures by oxidizing Ag-NCs to Ag2+ and Ag3+ states. Strong metal support interaction (SMSI) effect at the interface is indicated by a specific interaction seen in high-resolution transmission electron microscopy (HRTEM) images of CeO2/Ag-NCs, confirming Ag-NC encapsulation by deposited CeO2 layer after heating. Through chemisorption processes, the SMSI effect aids in the release of oxygen from the ceria surface by making a bond of Ag, O, and Ce. Consequently, employing silver as a supporting novel metal improves the redox behaviour of CeO2 at nearly 100°C. The band gap of cerium is modified because of this interaction as shown by UV-vis spectroscopy, influencing the electronic charge transport property of ceria. The current-voltage (I-V) characteristics in silver cluster supported ceria thin film verify the significant increase in current under visible light illumination as compared to the current in dark conditions. This renders that Ag-NCs supported CeO2 is suitable for photocatalysis and the capacitance-voltage (C-V) characteristic confirms the enhanced storage capacity of Ag-NCs /CeO2-based metal-oxide-semiconductor (MOS) devices qualifies it for use as non-volatile memory (NVM) devices.