Work

Photoinjection of High Potential Holes into Cu5Ta11O30 Nanoparticles by Porphyrin Dyes

Year: 2015

Type: article

Abstract: Excited-state hole injection into the valence band of Cu 5 Ta 11 O 30 nanoparticles (NP-Cu 5 Ta 11 O 30 ) was investigated through sensitization with zinc porphyrin dyes using simulated solar irradiance. The Cu 5 Ta 11 O 30 nanoparticles were prepared by a flux-mediated synthesis and found to have an average particle size of ∼10–15 nm by DLS and TEM. The zinc 4-(10,15,20-tris(4-pyridinyl)-porphin-5-yl)phenylphosphonic acid ( D1 ) and its analogue, in which the pyridine groups are methylated ( D2 ), were synthesized and found to have excited-state reduction potentials appropriate for p-type dye sensitization of the nanoparticles. The dye-sensitized NP-Cu 5 Ta 11 O 30 exhibited fluorescence quenching consistent with electron transfer from the NP-Cu 5 Ta 11 O 30 to the dye; forward and recombination rates were obtained by transient absorption measurements. Hole injection times of 8 ps and <100 fs were observed for D1 and D2, respectively. Nanoparticulate films of Cu 5 Ta 11 O 30 were prepared and evaluated in dye-sensitized solar cells under simulated solar irradiance (AM 1.5 G, 100 mW/cm 2 ). Measurable photocurrents and open-circuit potentials ( V oc ) of 200 and 110 mV were observed using D1 and D2, respectively.

Source: The Journal of Physical Chemistry C

DOI: 10.1021/acs.jpcc.5b02174