All earth abundant materials for low cost solar-driven hydrogen production

• All earth abundant materials based solar hydrogen (SH) production.
• Development of low cost Pt-free PECs for SH evolution.
• Sputter grown alloyed iron-silicide for auxiliary electrode in PECs.
• Chemical stability and performance evaluation of iron-silicide as electrode.
• The β-phase-FeSi(Al) yields similar hydrogen evolution rate as standard platinum.

Earth abundant materials based photoelectrochemical cells (PECs) are designed using aluminium alloyed iron silicide (FeSi(Al)) as auxiliary electrode, tungsten oxide (WO3) and iron-oxide (Fe2O3) as working electrodes for solar driven hydrogen (SH) production. Low temperature grown metallic α-phase and semiconducting β-phase FeSi(Al) are introduced as auxiliary electrode and hydrogen evolution performance is compared with commercially available platinum electrode. The β-phase FeSi(Al) electrode yields similar hydrogen evolution compared with platinum electrode and are highly stable in electrolyte solution. This study shows that the earth-abundant iron-silicide and cheap metal oxides based PEC cells provide great potential toward Pt-free devices for the development of sustainable and low cost PECs for large scale solar hydrogen production.