| Abstract: | Hematite is regarded as a promising photoanode for photoelectrochemical(PEC) water splitting.However,the charge recombination occurred at the interface of FTO/hematite strictly limits the PEC performance of hematite.Herein,we reported a Ti_3C_2 MXene underlayer modified hematite(Ti-Fe_2O_3) photoanode via a simple drop-casting followed by hydrothermal and annealing processes.Owing to the bifunctional role of Ti_3C_2 MXene underlayer in improving the interfacial properties of FTO/hematite and providing Ti source for the construction of Fe_2 TiO_5/Fe_2O_3 heterostructure in hematite nanostructure,the bulk and interfacial charge transfer dynamics of hematite are significantly enhanced,and consequently enhancing the PEC performance.Compared with the pristine hematite,the as-prepared Ti-Fe_2O_3 photoanode shows an increased photocurrent density from 0.80 mA/cm~2 to 1.30 mA/cm~2 at 1.23 V vs.RHE.Moreover,a further promoted PEC performance including a dramatically increased photocurrent density of 2.49 mA/cm~2 at1.23 V vs.RHE and an obviously lowered onset potential is achieved for the Ti-Fe_2O_3 sample after the subsequent surface F-treatment and the loading of FeNiOOH cocatalyst.Such results suggest that the introduction of Ti_3C_2 MXene underlayer is a facile but effective approach to improve the PEC water splitting activity of hematite. |
