Effect of aqueous media on photoelectrochemical water splitting performance of α-Fe2O3/LaFeO3:Cr tandem cell

A tandem cell that consists of an n-type (α-Fe 2 O 3 /hematite) photoanode and a p-type (LFO:Cr/chromium-doped lanthanum iron oxide) photocathode for solar water splitting has been demonstrated and studied for its photoelectrochemically. Under two-electrode system configurations, the PEC performance of α-Fe 2 O 3 exhibited a good photoanodic response with the highest photocurrent density achieved was 0.0047 mA and 0.066 mA cm −2 at 1.23 V (vs. LFO and LFO:Cr), respectively, as operated in 0.1 M KOH (pH 13) electrolyte. Furthermore, the tandem of (LFO and LFO:Cr) vs. α-Fe 2 O 3 also presented a similar increase of photocurrent responses as operated in different aqueous media. At zero bias condition, the highest photocurrent constructed in a two-electrode system was 0.0022 mA cm −2 for α-Fe 2 O 3 vs. LFO:Cr, which increased by 0.0006 mA cm −2 from α-Fe 2 O 3 vs. LFO tandem cell in 0.1 M KOH electrolyte. As a result, the solar-to-hydrogen (STH) efficiency of 0.0026% was achieved under AM 1.5 G illumination. Graphical Abstract