@article{spencer_holzapfel_you_mpourmpakis_augustyn_2024, title={Participation of electrochemically inserted protons in the hydrogen evolution reaction on tungsten oxides}, ISSN={["2041-6539"]}, DOI={10.1039/d4sc00102h}, abstractNote={Tungsten oxides undergo a significant increase in their hydrogen evolution reaction activity upon proton-insertion coupled electron transfer.}, journal={CHEMICAL SCIENCE}, author={Spencer, Michael A. and Holzapfel, Noah P. and You, Kyung-Eun and Mpourmpakis, Giannis and Augustyn, Veronica}, year={2024}, month={Mar} }
 @article{fortunato_zydlewski_lei_holzapfel_chagnot_mitchell_lu_jiang_milliron_augustyn_2023, title={Dual-Band Electrochromism in Hydrous Tungsten Oxide}, ISSN={["2330-4022"]}, DOI={10.1021/acsphotonics.3c00921}, abstractNote={The independent modulation of visible and near-infrared light by a single material, termed dual-band electrochromism, is highly desirable for smart windows to enhance the energy efficiency of buildings. Tungsten oxides are commercially important electrochromic materials, exhibiting reversible visible and near-infrared absorption when electrochemically reduced in an electrolyte containing small cations or protons. The presence of structural water in tungsten oxides has been associated with faster electrochromic switching speeds. Here, we find that WO3·H2O, a crystalline hydrate, exhibits dual-band electrochromism unlike the anhydrous WO3. This provides a heretofore unexplored route to tune the electrochromic response of tungsten oxides. Absorption of near-infrared light is achieved at low Li+/e– injection, followed by the absorption of visible light at higher Li+/e– injection as a result of an electrochemically induced phase transition. We propose that the dual-band modulation is possible due to the more open structure of WO3·H2O as compared to WO3. This facilitates a more extended solid-solution Li+ insertion regime that benefits the modulation of near-infrared radiation via plasmon absorption. Higher degrees of Li+/e– insertion lead to polaronic absorption associated with localized charge storage. These results inform how structural factors influence the electrochemically induced spectral response of transition-metal oxides and the important role of structural water beyond optical switching speed.}, journal={ACS PHOTONICS}, author={Fortunato, Jenelle and Zydlewski, Benjamin Z. and Lei, Ming and Holzapfel, Noah P. and Chagnot, Matthew and Mitchell, James B. and Lu, Hsin-Che and Jiang, De-en and Milliron, Delia J. and Augustyn, Veronica}, year={2023}, month={Sep} }