摘要
Due to the involvement of four-electron transfer process at photoanode,water oxidation is the ratelimiting step in water splitting reaction.To settle this dilemma,ZnCo_(2)O_(4)nanoparticles are combined with BiVO_(4)to form a p-n ZnCo_(2)O_(4)/BiVO;heterojunction photoanode,which is proved by an input voltage-output current test.The built-in electric field formed within the heterojunction structure promotes the effective separation of electrons and holes.ZnCo_(2)O_(4)is also an effective water oxidation cocatalyst,since it could cause the holes entering the electrode/electrolyte interface rapidly for the subsequent water oxidation reaction.The photocurrent density of ZnCo_(2)O_(4)/BiVO_(4)composite photoanode reaches 3.0 mA/cm^(2) at 1.23 V vs.RHE in 0.5 mol/L sodium sulfate under AM 1.5 G simulated sunlight,about 2.1 times greater than that of BiVO_(4)(1.4 mA/cm^(2)).These results suggest the potential of ZnCo_(2)O_(4)nanoparticles for improving photoelectrochemical water splitting anode materials.
基金
financially supported by the National Natural Science Foundation of China (Nos. 21808189 and 21663027)
Natural Science Basic Research Fund of Shaanxi Province (No.2020JZ20)
Fundamental Research Funds for the Central Universities of Chang’an University (No. 300102299304)。