Pyridyl-Anchored Type BODIPY Sensitizer-TiO2 Photocatalyst for Enhanced Visible Light-Driven Photocatalytic Hydrogen Production

Abstract

Dye-sensitized photocatalytic hydrogen production using a boron-dipyrromethene (BODIPY) organic material having a pyridyl group at the anchor site was investigated. Phenyl, carbazole, and phenothiazine derivatives were introduced into BODIPY dyes, and their photocatalytic activities were examined. Identification was performed by nuclear magnetic resonance (NMR), infrared (IR), mass (MS) spectra, and absorption spectra, and catalyst evaluation was performed by using visible-light irradiation and photocatalytic hydrogen production and photocurrent. These dyes have strong absorption at 600–700 nm, suggesting that they are promising as photosensitizers. When the photocatalytic activity was examined, stable catalytic performance was demonstrated, and the activity of the Pt-TiO2 photocatalyst carrying a dye having a carbazole group was 249 μmol/gcat·h. Photocurrent measurements suggest that dye-sensitized photocatalytic activity is occurring. This result suggests that BODIPY organic materials with pyridyl groups as anchor sites are useful as novel dye-sensitized photocatalysts.

BODIPY and dipyrrin as unexpected robust anchoring groups on TiO2 nanoparticles

“…Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopic measurements were performed using an Agilent Technologies Cary 600 Series FTIR spectrometer and a PIKE technologies GladiATR. 1 H, 11 B, 13 C, and 19 F NMR data were collected using an Agilent 400 MHz NMR instrument. A Bruker Dektak XT stylus profilometer was used to measure TiO 2 film thicknesses.…”

“…All sonication procedures were carried out with a benchtop bath sonicator. 31 have been synthesized by literature procedures and the structures were confirmed by 1 H, 11 B, 13 C, and 19 F NMR.…”

“…1d). 19 This method is synthetically simpler than for the carboxylic acid case, and the anchor proved stable for over 120 hours. Even with these improvements, there is still a need to look for other, more robust binding modes.…”

“…1 (a) BODIPY backbone and IUPAC numbering system for BODIPY dyes, (b) example of surface binding on TiO 2 via a carboxylic acid at the 8 position, 16 (c) example of surface binding by substitutions at the 3,5 positions, 17 (d) example of surface binding via a pyridine substitution at the 8 position. 19 though so far always attached through a specially introduced anchoring group. In many cases, the molecule is bound to the surface through a carboxylic group introduced into the para position of the 8-phenyl-BODIPY backbone (Fig.…”

Enhanced Photocatalytic Hydrogen Production Activity by Constructing a Robust Organic-Inorganic Hybrid Material Based Fulvalene and TiO2

“…Table S4: Comparison of H 2 evolution activity of TTF and TiO 2 photocatalytic systems. References [ 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 ] are cited in the supplementary materials.…”