Investigation of the Photocatalytic Hydrogen Production of Semiconductor Nanocrystal-Based Hydrogels

authored by

Jakob Cornelius Schlenkrich, Franziska Lübkemann-Warwas, Rebecca Tatjana Graf, Christoph Wesemann, Larissa Schoske, Marina Rosebrock, Karen Deli Josephine Hindricks, Peter Behrens, Detlef Bahnemann, Dirk Dorfs, Nadja-Carola Bigall

Abstract

Destabilization of a ligand-stabilized semiconductor nanocrystal solution with an oxidizing agent can lead to a macroscopic highly porous self-supporting nanocrystal network entitled hydrogel, with good accessibility to the surface. The previously reported charge carrier delocalization beyond a single nanocrystal building block in such gels can extend the charge carrier mobility and make a photocatalytic reaction more probable. The synthesis of ligand-stabilized nanocrystals with specific physicochemical properties is possible, thanks to the advances in colloid chemistry made in the last decades. Combining the properties of these nanocrystals with the advantages of nanocrystal-based hydrogels will lead to novel materials with optimized photocatalytic properties. This work demonstrates that CdSe quantum dots, CdS nanorods, and CdSe/CdS dot-in-rod-shaped nanorods as nanocrystal-based hydrogels can exhibit a much higher hydrogen production rate compared to their ligand-stabilized nanocrystal solutions. The gel synthesis through controlled destabilization by ligand oxidation preserves the high surface-to-volume ratio, ensures the accessible surface area even in hole-trapping solutions and facilitates photocatalytic hydrogen production without a co-catalyst. Especially with such self-supporting networks of nanocrystals, the problem of colloidal (in)stability in photocatalysis is circumvented. X-ray photoelectron spectroscopy and photoelectrochemical measurements reveal the advantageous properties of the 3D networks for application in photocatalytic hydrogen production.

Organisation(s)

Institute of Physical Chemistry and Electrochemistry
PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines
Laboratory of Nano and Quantum Engineering
Institute of Inorganic Chemistry
Institute of Technical Chemistry

External Organisation(s)

Saint Petersburg State University

Type

Article

Journal

Small

Volume

19

ISSN

1613-6810

Publication date

24.05.2023

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Chemistry(all), Materials Science(all), Biotechnology, Biomaterials

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy

Electronic version(s)

https://doi.org/10.1002/smll.202208108 (Access: Open)