Low-Cost Nanomaterials for Photoelectrochemical Water Splitting - Low-cost Nanomaterials: Toward Greener and More Efficient Energy Applications - page 280

Fig. 12 a Linear sweep
voltammograms collected for
air annealed hematite
(A-hematite) and hematite
annealed in N 2 (N-hematite)
at a scan rate of 10 mV/s in
1.0 M NaOH aqueous
solution, under
100 mW/cm 2 AM 1.5G
simulated solar light. b Mott-
Schottky plots measured for
A-hematite and N-hematite
nanowire films. Reproduced
with permission from [ 47 ]
common water oxidation catalyst. Zhong et al. deposited Co-Pi on silicon doped
hematite film by electrochemical deposition method [ 122 - 124 ]. The catalyst
modified hematite showed a negative shift of photocurrent onset potential, indi-
cating the suppression of water oxidation overpotential. Iridium oxide is another
promising water oxidation catalyst, although the cost is relatively higher than Co-
Pi catalyst. Tilley et al. used IrO 2 nanoparticle to modify silicon hematite and
studied their PEC performance (Fig. 13 ). A dramatic shift in the onset photocur-
rent potential was observed from 1.0 to 0.8 V versus RHE and plateau photo-
current density was enhanced from 3.45 to 3.75 mA/cm 2 , which achieved a new
benchmark photocurrent for hematite photoanode for PEC water splitting [ 90 ].