Decoupling of Light and Dark Reactions in a 2D Niobium Tungstate for Light-Induced Charge Storage and On-Demand Hydrogen Evolution
Yang Wang a, Yu-Te Chan b, Christoph Scheurer b, Bettina Lotsch a
a Max Planck Institute for Solid State Research, Heisenbergstraße, 1, Stuttgart, Germany
b Fritz-Haber-Institut derMax-Planck-Gesellschaf
Proceedings of MATSUS Fall 2025 Conference (MATSUSFall25)
E6 Photo-assisted chemical reactions: materials, characterization and mechanisms - #PhotoChem
València, Spain, 2025 October 20th - 24th
Organizers: Josep Albero Sancho and Menny Shalom
Oral, Yang Wang, presentation 019
Publication date: 21st July 2025

The direct coupling of light harvesting and charge storage in a single material opens new avenues to light storing devices. Here we demonstrate the decoupling of light and dark reactions in the two-dimensional layered niobium tungstate (TBA)+(NbWO6) for on-demand hydrogen evolution and solar battery energy storage [1]. Light illumination drives Li+/H+ photointercalation into the (TBA)+(NbWO6) photoanode, leading to small polaron formation assisted by structural distortions on the WOx sublattice, along with a light-induced decrease in material resistance over 2 orders of magnitude compared to the dark. The photogenerated electrons can be extracted on demand to produce solar hydrogen upon the addition of a Pt catalyst. Alternatively, they can be stored for over 20 h under oxygen-free conditions after 365 nm UV illumination for only 10 min, thus featuring a solar battery anode with promising capacity and long-term stability. The optoionic effects described herein offer new insights to overcome the intermittency of solar irradiation, while inspiring applications at the interface of solar energy conversion and energy storage, including solar batteries, “dark” photocatalysis, solar battolyzers, and photomemory devices.

Y.W. acknowledges a postdoctoral scholarship from the Max Planck Society and fellowship support from the Alexander von Humboldt Foundation. This work was supported by the Cluster of Excellence e-conversion EXC 2089/1 under Germany’s excellence strategy and the Max Planck Foundation via the Project SolBat. Additionally, Y.C. extends appreciation to the Max Planck Computing and Data Facility (MPCDF) for the generously allotted computing time.

© FUNDACIO DE LA COMUNITAT VALENCIANA SCITO
We use our own and third party cookies for analysing and measuring usage of our website to improve our services. If you continue browsing, we consider accepting its use. You can check our Cookies Policy in which you will also find how to configure your web browser for the use of cookies. More info