{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,18]],"date-time":"2025-10-18T15:08:49Z","timestamp":1760800129666,"version":"build-2065373602"},"reference-count":45,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2018,5,22]],"date-time":"2018-05-22T00:00:00Z","timestamp":1526947200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"FCT","doi-asserted-by":"publisher","award":["PTDC\/CTM-NAN\/3146\/2014","SFRH\/BPD\/84948\/2012"],"award-info":[{"award-number":["PTDC\/CTM-NAN\/3146\/2014","SFRH\/BPD\/84948\/2012"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>With the consistent shrinking of devices, micro-systems are, nowadays, widely used in areas such as biomedics, electronics, automobiles, and measurement devices. As devices shrunk, so too did their energy consumptions, opening the way for the use of nanogenerators (NGs) as power sources. In particular, to harvest energy from an object\u2019s motion (mechanical vibrations, torsional forces, or pressure), present NGs are mainly composed of piezoelectric materials in which, upon an applied compressive or strain force, an electrical field is produced that can be used to power a device. The focus of this work is to simulate the piezoelectric effect in different ZnO nanostructures to optimize the output potential generated by a nanodevice. In these simulations, cylindrical nanowires, nanomushrooms, and nanotrees were created, and the influence of the nanostructures\u2019 shape on the output potential was studied as a function of applied parallel and perpendicular forces. The obtained results demonstrated that the output potential is linearly proportional to the applied force and that perpendicular forces are more efficient in all structures. However, nanotrees were found to have an increased sensitivity to parallel applied forces, which resulted in a large enhancement of the output efficiency. These results could then open a new path to increase the efficiency of piezoelectric nanogenerators.<\/jats:p>","DOI":"10.3390\/nano8050354","type":"journal-article","created":{"date-parts":[[2018,5,23]],"date-time":"2018-05-23T03:14:24Z","timestamp":1527045264000},"page":"354","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["The Influence of Shape on the Output Potential of ZnO Nanostructures: Sensitivity to Parallel versus Perpendicular Forces"],"prefix":"10.3390","volume":"8","author":[{"given":"Jos\u00e9","family":"Cardoso","sequence":"first","affiliation":[{"name":"IFIMUP-IN, and Department of Physics and Astronomy, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 687, 4169-007 Porto, Portugal"}]},{"given":"Filipe F.","family":"Oliveira","sequence":"additional","affiliation":[{"name":"IFIMUP-IN, and Department of Physics and Astronomy, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 687, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0003-0491","authenticated-orcid":false,"given":"Mariana P.","family":"Proenca","sequence":"additional","affiliation":[{"name":"IFIMUP-IN, and Department of Physics and Astronomy, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 687, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0494-3009","authenticated-orcid":false,"given":"Jo\u00e3o","family":"Ventura","sequence":"additional","affiliation":[{"name":"IFIMUP-IN, and Department of Physics and Astronomy, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 687, 4169-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2018,5,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6949","DOI":"10.1002\/adfm.201401998","article-title":"Self-Compensated Insulating ZnO-Based Piezoelectric Nanogenerators","volume":"24","author":"Kim","year":"2014","journal-title":"Adv. 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