The serious effects of global warming make the transition towards renewable energy sources crucial for our society. Therefore, the development of sustainable materials capable of capturing and transforming solar energy into green chemical fuels has become of great interest. Semiconductors have demonstrated their ability to split water into O2 and H2, the latter being a valuable fuel. However, systems developed until now have several limitations. It is becoming increasingly evident that a single material will not be able to fully satisfy all the requirements to produce a device that can be considered practical for mass industrial use in terms of costs and efficiencies. Therefore, nanocomposites, where two or more compounds are combined in a new material at the nanoscale, are an interesting starting point towards the design of integrated systems for solar fuels production. In this work, we present the synthesis of ordered thin mesoporous TiO2 films prepared via a sol-gel approach and electrochemically modified by Ni-Fe layer double hydroxides (LDH), a state-of-the-art oxygen evolution reaction (OER) electrocatalyst. This soft chemistry synthesis allows fine tuning of the composition and crystallinity of the TiO2 skeleton, which determines the photocatalytic performance. Furthermore, the deposition of Ni-Fe LDH is useful in improving the reaction kinetics. The materials are being characterized by means of photoelectrochemical techniques, UV-vis spectroscopy, AFM, SEM and EDX (Fig. 1). The amount of catalyst and its Ni/Fe ratio will be adjusted to reach the optimal OER activity. Additionally, we intend to study the effect of magnetism, as it has been shown that the use of an external magnetic field enhances the oxygen evolution at magnetic catalysts. Our recent results show that these systems could act as promising composite photoanodes for photoelectrochemical water-splitting.

NiFe LDH modified mesoporous TiO2 thin films for photoelectrochemical water splitting

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.