Single-walled carbon nanotubes/nanocellulose hybrid films: towards thedevelopment of PEC water splitting photoanodes

Abstract

Resumen de la comunicación oral presentada en el Congreso ChemOnTubes 2022, celebrado en Donostia-San Sebastián (España) del 24 al 28 de Abril. ; Hydrogen is considered as one of the most suitable alternatives to fossil fuels if produced from water using renewable resources. Particularly, photoelectrochemical (PEC) water splitting is a well-known technology that allows to obtain green hydrogen through a combination of electricity and sunlight. This process requires photoelectrodes composed of a conductive substrate and a photoactive phase. The present work demonstrates that singlewalled carbon nanotubes (SWCNTs) can be processed along with nanocellulose, a biocompatible adjuvant that enables waterborne inks, into conductive films [1]. SWCNT inks were spray-coated over glass substrates in the form of films. Their low electrical resistivity values (Figure 1a) highlight that SWCNT films are valuable alternatives to typically employed opaque substrates in electrochemical devices, such as pyrolytic graphite. Subsequently, a TiO2 layer was deposited onto the SWCNT films, thus rendering the desired photoanodes (Figure 1b). Electrochemical measurements show that the as-prepared photoanodes display a noticeable photocurrent (Figure 1c), being a clear indicative of their water splitting activity. This is an unprecedented feature for this type of electrode configuration. ; Spanish MICINN/AEI: PID2019-104272RB-C51/AEI/10.13039/501100011033; Government of Aragón: Grupos Reconocidos DGA T03_20R.