Electron transfer and hydrogen generation from a molecular dyad: platinum(II) alkynyl complex anchored to [FeFe] hydrogenase subsite mimic.
A PS-Fe(2)S(2) molecular dyad 1a directly anchoring a platinum(II) alkynyl complex to a Fe(2)S(2) active site of a [FeFe] H(2)ase mimic, and an intermolecular system of its reference complexes 1b and 2, have been successfully constructed. Time-dependence of H(2) evolution shows that PS-Fe(2)S(2)1a as well as complex 2 with 1b can produce H(2) in the presence of a proton source and sacrificial donor under visible light irradiation. Spectroscopic and electrochemical studies on the electron transfer event reveal that the reduced Fe(I)Fe(0) species generated by the first electron transfer from the excited platinum(II) complex to the Fe(2)S(2) active site in PS-Fe(2)S(2)1a and complex 2 with 1b is essential for photochemical H(2) evolution, while the second electron transfer from the excited platinum(II) complex to the protonated Fe(I)Fe(0) species is thermodynamically unfeasible, which might be an obstacle for the relatively small amount of H(2) obtained by PS-Fe(2)S(2) molecular dyads reported so far.
Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, the Chinese Academy of Sciences, Beijing, 100190, PR China.
Wen-Guang
WG
Wang
Feng
F
Wang
Hong-Yan
HY
Wang
Chen-Ho
CH
Tung
Li-Zhu
LZ
Wu
D000480:Alkynes / Q000737:chemistry*; D040761:Biomimetic Materials / Q000737:chemistry*; D020134:Catalytic Domain; D004563:Electrochemistry; D004579:Electron Transport; D006859:Hydrogen / Q000737:chemistry*; D006864:Hydrogenase / Q000737:chemistry*; D007506:Iron-Sulfur Proteins / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*
D000480:Alkynes; D007506:Iron-Sulfur Proteins; D009942:Organometallic Compounds; D010984:Platinum; D006859:Hydrogen; C118830:iron hydrogenase; D006864:Hydrogenase