| 초록 |
We demonstrated herein that reduced graphene oxide (rGO), a low cost, chemically stable, and high-conductivity material, can be used as a hole-transporting layer to fabricate Co3O4-rGO-BiVO4 photoanodes that show excellent photoelectrochemical (PEC) water splitting performance. The Co3O4/rGO/BiVO4 photoanode achieved a remarkable photocurrent density of 2.6 mA cm-2 at 1 V vs. SCE under AM 1.5G solar light irradiation, which is a 3.7-fold increase compared with that of pristine BiVO4 (0.7 mA cm-2). The highest incident photon-to-current conversion efficiency (IPCE) achieved was 40.3% at 430 nm, and the maximum surface charge injection efficiency (ηi) reached was 57% at 0.5 V versus SCE, which are nearly 4 and 5.7 times higher than that of a pristine BiVO4 photoanode, respectively. The Co3O4-rGO-BiVO4 photoanode exhibited a highly stable photocurrent density for at least 3 h. Collectively, the results demonstrate that rGO shows great potential as a hole-transporting layer for photoanodes and that Co3O4-rGO-BiVO4 is an efficient and stable photoanode structure that shows promise for PEC water splitting applications. |
