Light-driven charge transfer in nano-Fe() complexes facilitates the oxidation of water

• Published in: New journal of chemistry 2016, Vol.4 (7), p.653-658
• Main Authors: Wang, Yin-Bing, Qu, Ling-Ling, Chen, Qiu-Yun, Feng, Chang-Jian
• Format: Article
• Language: English
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/c6nj00121a

The design and preparation of highly active, environmentally friendly photo-catalysts with low cytotoxicity for the oxidation of water are important in achieving the efficient splitting of water. We present a novel supramolecular nanocomplex BODIPY@Fe 1 obtained by assembling a flower-like nano-Fe( iii ) complex (PPM@Fe) with 8-(4-methoxyphenyl)boron-dipyrromethane (BODIPY) through a hydrogen bond. This complex catalysed the oxidative conversion of water to dioxygen. The hydrogen bond C&z.dbd;O H(N)-F- facilitated the charge transfer interaction between the ligand and the metal centre in BODIPY@Fe. The TOF value of BODIPY@Fe/H 2 O (7.76 h −1 ) was much higher than that of the PPM@Fe/Ru(bpy) 3 Cl 2 /Na 2 S 2 O 8 system (3.06 h −1 ). Electron paramagnetic resonance spectrometry and water oxidation activity data indicated that the high-spin Fe( iii ) species in the BODIPY@Fe complex was involved during the catalysed oxidation of water. The formation of the Fe-O and O-O bonds were confirmed. BODIPY@Fe can also catalyse the oxidative degradation of methylene blue using water as the oxygen source. Hence the assembly of a photosensitizer with an Fe( iii ) complex of pyrrole-conjugated carbonyl group derivatives provides a promising green generator of dioxygen via photoirradiation. BODIPY@Fe 1 catalysed the oxidation of water with efficient energy transfer from the BODIPY antenna to the Fe 1 through hydrogen.