Abstract
Tungsten trioxide (WO3) is an intrinsic n-type semiconductor that can be prepared to exhibit a piezoresponse through doping and heat treatment strategies. We report the piezoresponse in platinum-doped WO3 thin films, prepared by RF/DC cosputtering, followed by postdeposition annealing at 600 °C. Measurements using Switching Spectroscopy Piezo Force Microscopy (SS-PFM) reveal domains with different polarization orientations and hysteresis behavior, corresponding to a piezoelectric coefficient of d33 = 97 ± 6 pmV-1. Low-angle x-ray diffraction (XRD) indicates the presence of an orthorhombic structure (β-WO3) with a Pbcn space group, while Scanning Transmission Electron Microscopy (STEM) reveals the formation of platinum nanoparticles (∼5 nm) with a cubic structure (Fm(Formula presented)m). Atom Probe Tomography (APT) confirms the formation of Pt nanoparticles and Ar-enriched cavities within the WO3 matrix induced by the annealing process. These structural modifications create lattice strain, giving rise to piezoelectric domains with different polarization orientations.
| Original language | English |
|---|---|
| Pages (from-to) | 17249-17256 |
| Number of pages | 8 |
| Journal | ACS Omega |
| Volume | 10 |
| Issue number | 17 |
| DOIs | |
| State | Published - May 6 2025 |
| Externally published | Yes |
Funding
P.M.P.-D. thanks Secretaría de Ciencia, Humanidades, Tecnología e Innovación (SECIHTI)-México for graduate scholarship #956889 at Universidad Autónoma de Ciudad Juárez and Dirección General de Vinculación e Intercambio of UACJ for the summer 2023 international traveling stipend. This work was partially funded by SECIHTI-México under the Sistema Nacional de Investigadoras e Investigadores Fellowship program of SECIHTI CVU#222146 for 2020-2025 (M.R.). Part of this work was performed at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated by the U.S. Department of Energy (DOE) Office of Science. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a fully owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000. Additional funding was provided by the Karlsruhe Nano and Micro Facility (KNMF) of the Karlsruhe Institute of Technology for the usage of APT and FIB instruments under proposal 2023-030-031793. The KNMF grants measurement time to external users for proposals pertinent to KNMF goals. Article publication charges were supported by the Institutional Open Access Program (IOAP) of the Karlsruhe Institute of Technology-Helmholtz and organized by Projekt DEAL. We thank Centro de Investigación en Materiales Avanzados-Chihuahua (CIMAV), Universidad Autónoma de Ciudad Juárez (UACJ), the Center for Integrated Nanotechnologies (CINT) of Sandia National Laboratories at Albuquerque, NM, and Karlsruhe Micro and Nano Facilities of the Karlsruhe Institute of Technology in Germany for the usage of all laboratory facilities and equipment. We thank the Programa de Movilidad at Universidad Autonóma de Ciudad Juárez (UACJ) for providing support through the summer research scholarship at the Karlsruhe Nano Micro Facility (KNMF), which was awarded to students involved in this project and greatly contributed to its success and our academic development. We also thank Dr. Oscar A. López-Galán for providing insights and comments on the main manuscript.