Anomalous Photoresponse in a Reduced Metal-Semiconductor Hybrid of Nickel and Titanium Oxide

TL;DR

This study investigates a novel nickel-titanium oxide nanostructure that enhances photoresponse efficiency and demonstrates self-powered photodetector potential through combined photo-driven and photothermal mechanisms.

Contribution

It introduces a new eutectic NiTiO₃-TiO₂ architecture with nanostructuring that improves photoactive device performance and elucidates the underlying carrier mechanisms.

Findings

Enhanced photoresponse efficiency due to nanostructuring.

Identification of competing photo-driven and photothermal mechanisms.

Potential for self-powered photodetectors.

Abstract

Eutectic NiTiO$_3$-TiO$_2$ samples and their H$_2$ reduced Ni-TiO$_2$ samples, where high aspect ratio TiO$_2$ nanostructures are axially decorated with nodular Ni globules, are thoroughly explored to understand their effect in photo-response. We show that by employing this novel eutectic architecture, effectively exploiting the nano-structuring process along with the chosen material properties, the overall efficiency of the ensuing photoactive device is improved. We also show the competing photo-driven and photothermal-driven carrier mechanisms to define the total photo-response of the system. Additionally, the ability to function self-powered poses this approach as a potential strategy for achieving efficient photodetectors.