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This is the peer reviewed version of the following article: Zheng, X., Mofarah, S. S., Cazorla, C., Daiyan, R., Esmailpour, A. A., Scott, J., Yao, Y., Lim, S., Wong, V., Chen, E. Y., Arandiyan, H., Koshy, P., Sorrell, C. C., Decoupling the Impacts of Engineering Defects and Band Gap Alignment Mechanism on the Catalytic Performance of Holey 2D CeO2−x-Based Heterojunctions. Adv. Funct. Mater. 2021, 31, 2103171, which has been published in final form at https://doi.org/10.1002/adfm.202103171. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley's version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited. ; Critical catalysis studies often lack elucidation of the mechanistic role of defect equilibria in solid solubility and charge compensation. This approach is applied to interpret the physicochemical properties and catalytic performance of a free-standing 2D–3D CeO2-x scaffold, which is comprised of holey 2D nanosheets, and its heterojunctions with MoO3-x and RuO2. The band gap alignment and structural defects are engineered using density functional theory (DFT) simulations and atomic characterization. Further, the heterojunctions are used in hydrogen evolution reaction (HER) and catalytic ozonation applications, and the impacts of the metal oxide heteroatoms are analyzed. A key outcome is that the principal regulator of the ozonation performance is not oxygen vacancies but the concentration of Ce3+ and Ce vacancies. Cation vacancy defects are measured to be as high as 8.1 at% for ...

This article belongs to the Special Issue Luminescence Properties of Nanomaterials and Nanocomposites. ; Band gap engineering of atomically thin two-dimensional (2D) materials has attracted a huge amount of interest as a key aspect to the application of these materials in nanooptoelectronics and nanophotonics. Low-loss electron energy loss spectroscopy has been employed to perform a direct measurement of the band gap in atomically thin MoxW(1−x)S2 nanoflakes. The results show a bowing effect with the alloying degree, which fits previous studies focused on excitonic transitions. Additional properties regarding the Van Hove singularities in the density of states of these materials, as well as high energy excitonic transition, have been analysed as well. ; Research supported by the Spanish MICINN (PID2019-104739GB-100/AEI/10.13039/ 501100011033), Government of Aragon (project DGA E13-20R) and European Union H2020 programs "ESTEEM3" (823717), Graphene Flagship (881603), JST-CREST (JPMJCR20B1, JPMJCR20B5, JPMJCR1993) and JSPS A3 Foresight Program. ; Peer reviewed

The final publication is available via https://doi.org/10.1021/acsnano.9b02843 . ; Austrian Science Funds (FWF) ; German Research Foundation (DFG) ; European Union's Horizon 2020

This work proposes a solution for an isolated gate driver for SiC MOSFETs, based on a magnetic transformer that simultaneously provides to the secondary side the turn-on and turn-off gate signals and the power required for an adequate gate control. This avoids the use of a dedicated DC-DC isolated converter and optocoupler. The original pulse signal is converted into impulses, avoiding transformer saturation at any duty ratio operation. The small size of the resulting transformer enables an overall size reduction vs. conventional solutions (based either in magnetic or optocoupler + power supply). This enables much more compact designs, which are critical in high-power density applications and multilevel converters. After describing the basic operation of the driver, experimental results on a 2kW prototype demonstrate the feasibility of the proposal. It is worth mentioning that this design is also suitable for GaN devices with minor design changes ; This work has been partially supported by the Spanish Government, under the research mobility grant PRX15/00594, for professors and researchers in foreign higher education and research institutions (MECD), and under research grants ENE2013-44245-R, Project "Microholo" (Innovation Development and Research Office-MEC,), and by the European Union through ERFD Structural Funds (FEDER)