am5b09902_si_001.pdf (448.81 kB)
Download file

H2 Photogeneration Using a Phosphonate-Anchored Ni-PNP Catalyst on a Band-Edge-Modified p‑Si(111)|AZO Construct

Download (448.81 kB)
journal contribution
posted on 20.01.2016, 00:00 by Hark Jin Kim, Junhyeok Seo, Michael J. Rose
We report the fabrication of a {semiconductor}|{metal oxide}|{molecular catalyst} construct for the photogeneration of dihydrogen (H2) under illumination, including band-edge modulation of the semiconductor electrode depending on the identity of Si(111)–R and the metal oxide. Briefly, a synergistic band-edge modulation is observed upon (i) the introduction of a p-Si|n-AZO heterojunction and (ii) introduction of an organic dimethoxyphenyl (diMeOPh) group at the heterojunction interface; the AZO also serves as a transparent and conductive conduit, which was capped with an ultrathin layer (20 Å) of amorphous TiO2 for stability. A phosphonate-appended PNP ligand and its Ni complex were then adsorbed to the p/n heterojunction for photoelectrochemical H2 generation (figures of merit: Vonset ≈ + 0.03 V vs NHE, Jmax ≈ 8 mA cm–2 at 60 mM TsOH).