Organic-Inorganic Hybrid Solution-Processed H₂-Evolving Photocathodes.
Here we report for the first time an H2-evolving photocathode fabricated by a solution-processed organic-inorganic hybrid composed of CdSe and P3HT. The CdSe:P3HT (10:1 (w/w)) hybrid bulk heterojunction treated with 1,2-ethanedithiol (EDT) showed efficient water reduction and hydrogen generation. A photocurrent of -1.24 mA/cm(2) at 0 V versus reversible hydrogen electrode (V(RHE)), EQE of 15%, and an unprecedented Voc of 0.85 V(RHE) under illumination of AM1.5G (100 mW/cm(2)) in mild electrolyte were observed. Time-resolved photoluminescence (TRPL), internal quantum efficiency (IQE), and transient photocurrent measurements were carried out to clarify the carrier dynamics of the hybrids. The exciton lifetime of CdSe was reduced by one order of magnitude in the hybrid blend, which is a sign of the fast charge separation upon illumination. By comparing the current magnitude of the solid-state devices and water-splitting devices made with identical active layers, we found that the interfaces of the water-splitting devices limit the device performance. The electron/hole transport properties investigated by comparing IQE spectra upon front- and back-side illumination evidenced balanced electron/hole transport. The Faradaic efficiency is 80-100% for the hybrid photocathodes with Pt catalysts and ∼70% for the one without Pt catalysts.
Zernike Institute for Advanced Materials, University of Groningen , Nijenborgh 4, Groningen 9747 AG, The Netherlands.
Lai-Hung
LH
Lai
Zernike Institute for Advanced Materials, University of Groningen , Nijenborgh 4, Groningen 9747 AG, The Netherlands.
Widianta
W
Gomulya
Zernike Institute for Advanced Materials, University of Groningen , Nijenborgh 4, Groningen 9747 AG, The Netherlands.
Matthijs
M
Berghuis
Department of Chemistry and Applied Biosciences, ETH Zürich , Wolfgang-Pauli-Strasse 10, Zurich 8049, Switzerland.|EMPA-Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, Dübendorf 8600, Switzerland.
Loredana
L
Protesescu
Van't Hoff Institute for Molecular Sciences, University of Amsterdam , Science Park 904, 1098 XH Amsterdam, The Netherlands.
Remko J
RJ
Detz
Van't Hoff Institute for Molecular Sciences, University of Amsterdam , Science Park 904, 1098 XH Amsterdam, The Netherlands.
Joost N H
JN
Reek
Department of Chemistry and Applied Biosciences, ETH Zürich , Wolfgang-Pauli-Strasse 10, Zurich 8049, Switzerland.|EMPA-Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, Dübendorf 8600, Switzerland.
Maksym V
MV
Kovalenko
Zernike Institute for Advanced Materials, University of Groningen , Nijenborgh 4, Groningen 9747 AG, The Netherlands.
Maria A
MA
Loi
H2 generation; colloidal nanocrystal; organic−inorganic hybrids; photocathode; photoelectrochemical water splitting