| Photocatalytic water splitting is an ideal way to produce hydrogen as an efficient,clean and renewable energy source,which can meet a growing global energy demand.However,as a half reaction of water splitting,water oxidation is considered to be the bottleneck due to the sluggish kinetics for such a multi-electron transfer process.On the other hand,the separation of the highly explosive hydrogen and oxygen mixture gas is indispensable and increases the equipment cost.Compared with water oxidation reaction,the oxidation of organic substrates is easier to implement in terms of their thermodynamics and kinetics,so the integration of the oxidation of organic substrates with the reduction of hydrogen proton is promising for the solar driven hydrogen production.Based on the high selectivity of molecular catalyst and the stability of semiconductor in the light-absorbing,the system includes the oxidation of alcohols and the reduction of hydrogen proton was then constructed in aqueous solution,which employed the synthesized Co?dmgH?2?4-CH2-PO3H2-py?Cl][?dmgH=dimethylglyoxime?,?Py=pyridine?]and[Ru?tpa??H2O?2]?PF6?2]?tpa=tris?2-pyridylmethyl?amine?as catalysts,g-C3N4 semiconductor as light-absorbing component.After 20h irradiation,the conversion and selection efficiency for the obtained 4-Methoxybenzyl alcohol were 37%and 99%,respectively,and the amount of produced hydrogen was determined to be 37.2?mol.In addition,the oxidation of organic substrates can be achieved by dye-sensitized photoelectrochemical cells?PEC?.To construct the PEC,three kinds of manganese porphyrin complexes,Mn1,Mn2,Mn3 with various adsorption groups were synthesized,respectively.Then the molecular catalysts and photosensitizer were coloaded on TiO2 surface for photoanode for the further photoelectrochemical test.Porphyrin derived Mn3 with phosphate anchoring groups was found to exhibit the best performance for PEC oxidation of the organic substrate. |
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