{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,16]],"date-time":"2026-03-16T13:47:34Z","timestamp":1773668854331,"version":"3.50.1"},"reference-count":46,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,3,30]],"date-time":"2021-03-30T00:00:00Z","timestamp":1617062400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/50011\/2020, UIDP\/50011\/2020"],"award-info":[{"award-number":["UIDB\/50011\/2020, UIDP\/50011\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["Decree-Law 57\/2016"],"award-info":[{"award-number":["Decree-Law 57\/2016"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100010665","name":"H2020 Marie Sk\u0142odowska-Curie Actions","doi-asserted-by":"publisher","award":["778070"],"award-info":[{"award-number":["778070"]}],"id":[{"id":"10.13039\/100010665","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002261","name":"Russian Foundation for Basic Research","doi-asserted-by":"publisher","award":["20-58-0061"],"award-info":[{"award-number":["20-58-0061"]}],"id":[{"id":"10.13039\/501100002261","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100007595","name":"Belarusian Republican Foundation for Fundamental Research","doi-asserted-by":"publisher","award":["T20R-359"],"award-info":[{"award-number":["T20R-359"]}],"id":[{"id":"10.13039\/100007595","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Pure BiFeO3 (BFO) and doped Bi0.9La0.1FeO3 (BLFO) thin films were prepared on Pt\/TiO2\/SiO2\/Si substrates by a modified sol\u2013gel technique using a separate hydrolysis procedure. The effects of final crystallization temperature and La doping on the phase structure, film morphology, and nanoscale piezoelectric properties were investigated. La doping and higher crystallization temperature lead to an increase in the grain size and preferred (102) texture of the films. Simultaneously, a decrease in the average effective piezoelectric coefficient (about 2 times in La-doped films) and an increase in the area of surface non-polar phase (up to 60%) are observed. Phase separation on the films\u2019 surface is attributed to either a second phase or to a non-polar perovskite phase at the surface. As compared with undoped BFO, La-doping leads to an increase in the average grain size and self-polarization that is important for future piezoelectric applications. It is shown that piezoelectric activity is directly related to the films\u2019 microstructructure, thus emphasizing the role of annealing conditions and La-doping that is frequently used to decrease the leakage current in BFO-based materials.<\/jats:p>","DOI":"10.3390\/ma14071694","type":"journal-article","created":{"date-parts":[[2021,3,30]],"date-time":"2021-03-30T09:57:04Z","timestamp":1617098224000},"page":"1694","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Nanoscale Piezoelectric Properties and Phase Separation in Pure and La-Doped BiFeO3 Films Prepared by Sol\u2013Gel Method"],"prefix":"10.3390","volume":"14","author":[{"given":"Alina V.","family":"Semchenko","sequence":"first","affiliation":[{"name":"Faculty of Physics and Information Technology, Francisk Skorina Gomel State University, 246019 Gomel, Belarus"}]},{"given":"Vitaly V.","family":"Sidsky","sequence":"additional","affiliation":[{"name":"Faculty of Physics and Information Technology, Francisk Skorina Gomel State University, 246019 Gomel, Belarus"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6318-1425","authenticated-orcid":false,"given":"Igor","family":"Bdikin","sequence":"additional","affiliation":[{"name":"TEMA, Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Vladimir E.","family":"Gaishun","sequence":"additional","affiliation":[{"name":"Faculty of Physics and Information Technology, Francisk Skorina Gomel State University, 246019 Gomel, Belarus"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3347-8628","authenticated-orcid":false,"given":"Svitlana","family":"Kopyl","sequence":"additional","affiliation":[{"name":"Department of Physics, CICECO-Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Dmitry L.","family":"Kovalenko","sequence":"additional","affiliation":[{"name":"Faculty of Physics and Information Technology, Francisk Skorina Gomel State University, 246019 Gomel, Belarus"}]},{"given":"Oleg","family":"Pakhomov","sequence":"additional","affiliation":[{"name":"Laboratory for \u201cElectro-and Magnetocaloric Materials and Structures\u201d, ITMO University, 197101 St. Petersburg, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7068-7061","authenticated-orcid":false,"given":"Sergei A.","family":"Khakhomov","sequence":"additional","affiliation":[{"name":"Faculty of Physics and Information Technology, Francisk Skorina Gomel State University, 246019 Gomel, Belarus"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3432-7610","authenticated-orcid":false,"given":"Andrei L.","family":"Kholkin","sequence":"additional","affiliation":[{"name":"Department of Physics, CICECO-Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"022905","DOI":"10.1063\/1.4813419","article-title":"Tuning the switching time of BiFeO3 capacitors by electrodes\u2019 conductivity","volume":"103","author":"Guo","year":"2013","journal-title":"Appl. Phys. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"096107","DOI":"10.1063\/1.4894758","article-title":"Enhancement of switching speed of BiFeO3 capacitors by magnetic fields","volume":"2","author":"Guo","year":"2014","journal-title":"APL Mater."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"335","DOI":"10.1016\/j.pmatsci.2016.09.001","article-title":"Multiferroic bismuth ferrite-based materials for multifunctional applications: Ceramic bulks, thin films and nanostructures","volume":"84","author":"Wu","year":"2016","journal-title":"Prog. Mater. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"3764","DOI":"10.1038\/s41467-018-06190-5","article-title":"Complex strain evolution of polar and magnetic order in multiferroic BiFeO3 thin films","volume":"9","author":"Chen","year":"2018","journal-title":"Nat. Commun."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1016\/j.apsusc.2018.05.074","article-title":"Effect of annealing atmosphere on the ferroelectric properties of inkjet printed BiFeO3 thin films","volume":"454","author":"Li","year":"2018","journal-title":"Appl. Surf. Sci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1017","DOI":"10.1016\/j.apsusc.2018.12.082","article-title":"Efficient synthesis of BiFeO3 by the microwave-assisted sol-gel method: \u201cA\u201dsite influence on the photoelectrochemicalactivity of perovskites","volume":"471","author":"Singh","year":"2019","journal-title":"Appl. Surf. Sci."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"947","DOI":"10.1021\/acs.chemmater.8b04380","article-title":"Band gap tuning of solution processed ferroelectric perovskite BiFe1\u2212xCoxO3 thin films","volume":"31","author":"Machado","year":"2019","journal-title":"Chem. Mater."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1686","DOI":"10.1016\/j.ssc.2011.08.002","article-title":"Structural stability and magnetic properties of Bi1\u2212xLa(Pr)xFeO3 solid solutions","volume":"151","author":"Karpinsky","year":"2011","journal-title":"Solid State Commun."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"054109","DOI":"10.1103\/PhysRevB.83.054109","article-title":"Isothermal structural transitions, magnetization and large piezoelectric response in Bi1-xLaxFeO3 perovskites","volume":"83","author":"Troyanchuk","year":"2011","journal-title":"Phys. Rev. B."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1016\/j.matlet.2013.08.022","article-title":"Magnetoelectric coupling in multiferroic Tb-doped BiFeO3 nanoparticles","volume":"111","author":"Verma","year":"2013","journal-title":"Mater. Lett."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"132907","DOI":"10.1063\/1.4822327","article-title":"The effects of La substitution on ferroelectric domain structure and multiferroic properties of epitaxially grown BiFeO3 thin films","volume":"103","author":"Kim","year":"2013","journal-title":"Appl. Phys. Lett."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"318","DOI":"10.1186\/s11671-016-1534-2","article-title":"Local magnetoelectric effect in La-doped BiFeO3 multiferroic thin films revealed by magnetic-field-assisted scanning probe microscopy","volume":"11","author":"Pan","year":"2016","journal-title":"Nanoscale Res. Lett."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"255","DOI":"10.17586\/2220-8054-2019-10-3-255-265","article-title":"Tunable multiferroic properties of cerium doped bismuth ferrite","volume":"10","author":"Patel","year":"2019","journal-title":"Nanosyst. Phys. Chem. Math."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1180","DOI":"10.1016\/j.jpcs.2011.07.017","article-title":"Effect of Gd doping on structural, electrical and magnetic properties of BiFeO3 electroceramic","volume":"72","author":"Pradhan","year":"2011","journal-title":"J. Phys. Chem. Solids"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"102299","DOI":"10.1016\/j.rinp.2019.102299","article-title":"Enhanced dielectric, magnetic and optical properties of Cr-doped BiFeO3 multiferroic nanoparticles synthesized by sol-gel route","volume":"13","author":"Sinha","year":"2019","journal-title":"Results Phys."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"123535","DOI":"10.1063\/1.3436593","article-title":"Influence of Zr doping on the structure and ferroelectric properties of BiFeO3 thin films","volume":"107","author":"Mukherjee","year":"2010","journal-title":"J. Appl. Phys."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"19","DOI":"10.4283\/JMAG.2011.16.1.019","article-title":"Effects of Mn doping on structural and magnetic properties of multiferroic BiFeO3 nanograins made by sol-gel method","volume":"16","author":"Raghavender","year":"2011","journal-title":"J. Magn."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1604720","DOI":"10.1002\/adfm.201604720","article-title":"Efficient and flexible thin film amorphous silicon solar cells on nanotextured polymer substrate using sol-gel based nanoimprinting method","volume":"27","author":"Zhang","year":"2017","journal-title":"Adv. Funct. Mater."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"158","DOI":"10.1016\/j.surfcoat.2017.10.079","article-title":"Sol-gel deposition of hydroxyapatite coatings on porous titanium for biomedical applications","volume":"333","author":"Peon","year":"2018","journal-title":"Surf. Coat. Technol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"137456","DOI":"10.1016\/j.tsf.2019.137456","article-title":"Ceramic coating for delayed degradation of Mg-1.2Zn-0.5Ca-0.5Mn bone fixation and instrumentation","volume":"687","author":"Ibrahim","year":"2019","journal-title":"Thin Solid Film"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1016\/S1002-0721(14)60065-X","article-title":"La3+-doped SrBi2Ta2O9 thin films for FRAM synthesized by sol-gel method","volume":"32","author":"Sidsky","year":"2014","journal-title":"J. Rare Earths"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"621","DOI":"10.1016\/0025-5408(84)90130-2","article-title":"Well Densified NASICON Type Ceramics, Elaborated Using Sol-Gel Process and Sintering at Low Temperatures","volume":"19","author":"Perthuis","year":"1984","journal-title":"Mater. Res. Bull."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/0272-8842(89)90005-9","article-title":"Gel Technology in Ceramics, Glass Ceramics and Ceramic-Ceramic Compositest","volume":"15","author":"Colomban","year":"1989","journal-title":"Ceram. Int."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"312","DOI":"10.3390\/ceramics3030029","article-title":"Chemical Preparation Routes and Lowering the Sintering Temperature of Ceramics","volume":"3","author":"Colomban","year":"2020","journal-title":"Ceramics"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1629","DOI":"10.1111\/j.1551-2916.2009.03240.x","article-title":"Electromechanical imaging and spectroscopy of ferroelectric and piezoelectric materials: State-of-the-art and prospects for the future (feature article)","volume":"92","author":"Balke","year":"2009","journal-title":"J. Am. Ceram. Soc."},{"key":"ref_26","unstructured":"(2020, July 01). International Centre for Diffraction Data. Available online: http:\/\/www.icdd.com."},{"key":"ref_27","unstructured":"(2020, July 04). Crystallographic Computing System for Standard and Modulated Structures. Available online: http:\/\/jana.fzu.cz\/workshops\/Jana2006%20Cookbook.pdf."},{"key":"ref_28","unstructured":"Cullity, B.D., and Stock, S.R. (2001). Elements of X-ray Diffraction, Prentice-Hall. [3rd ed.]."},{"key":"ref_29","unstructured":"(2020, July 04). Open Source XRD Rietvield Refinement. Available online: http:\/\/profex.doebelin.org."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"8729","DOI":"10.1016\/j.ceramint.2013.04.058","article-title":"Effects of annealing temperature on the microstructure, optical, ferroelectric and photovoltaic properties of BiFeO3 thin films prepared by sol-gel method","volume":"39","author":"Lin","year":"2013","journal-title":"Ceram. Int."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Semchenko, A.V., Khakhomov, S.A., Sidsky, V.V., Gaishun, V.E., Kovalenko, D.L., Strek, W., and Hreniak, D. (2019, January 4\u20137). Structural properties of BiFeO3 and Bi0,9La0,1FeO3 powders synthesized by sol-gel process. Proceedings of the International Conference on Global Research and Education, Balatonf\u00fcred, Hungary.","DOI":"10.1007\/978-3-030-36841-8_11"},{"key":"ref_32","first-page":"1993","article-title":"BiFeO3 ceramics: Processing, electrical, and electromechanical properties","volume":"97","author":"Rojac","year":"2014","journal-title":"J. Am. Chem. Soc."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"2127","DOI":"10.1557\/JMR.2005.0263","article-title":"Synthesis of oriented BiFeO3 thin films by chemical solution deposition: Phase, texture, and microstructural development","volume":"20","author":"Tyholdt","year":"2005","journal-title":"J. Mater. Res."},{"key":"ref_34","unstructured":"(2020, September 01). Gwyddion\u2014Free SPM (AFM, SNOM, NSOM, STM, MFM, \u2026) Data Analysis Software. Available online: http:\/\/www.gwyddion.net."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"235703","DOI":"10.1088\/0957-4484\/21\/23\/235703","article-title":"Local piezoelectric properties of ZnO thin films prepared by RF-plasma-assisted pulsed-laser deposition method","volume":"21","author":"Bdikin","year":"2010","journal-title":"Nanotechnology"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"204109","DOI":"10.1063\/1.4879899","article-title":"Physics of the multi-functionality of lanthanum ferrite ceramics","volume":"115","author":"Bhargav","year":"2014","journal-title":"J. Appl. Phys."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1016\/j.jallcom.2012.12.055","article-title":"Evolution of crystal structure and ferroic properties of La-doped BiFeO3 ceramics near the rhombohedral-orthorhombic phase boundary","volume":"555","author":"Karpinsky","year":"2013","journal-title":"J. Alloys Compd."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1016\/j.actamat.2016.11.063","article-title":"The effect of phase assemblages, grain boundaries and domain structure on the local switching behavior of rare-earth modified bismuth ferrite ceramics","volume":"125","author":"Alikin","year":"2017","journal-title":"Acta Mater."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1016\/j.matlet.2015.08.014","article-title":"Enhanced magnetization and electric polarization in Bi2Fe4O9 ceramics by magnetic field pre-sintering","volume":"160","author":"Huang","year":"2015","journal-title":"Mater. Lett."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"4092","DOI":"10.1039\/C6TC00243A","article-title":"Chemical route derived bismuth ferrite thin films and nanomaterials","volume":"4","author":"Zhang","year":"2016","journal-title":"J. Mater. Chem. C"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"525","DOI":"10.1080\/10584589808208071","article-title":"Self-polarization effect in Pb(Zr,Ti)O3 thin films","volume":"22","author":"Kholkin","year":"1998","journal-title":"Integr. Ferroelectr."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"054101","DOI":"10.1063\/1.4960137","article-title":"Thickness effect on the structure, grain size, and local piezoresponse of self-polarized lead lanthanum zirconate titanate thin films","volume":"120","author":"Melo","year":"2016","journal-title":"J. Appl. Phys."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"3548","DOI":"10.1016\/j.materresbull.2012.06.058","article-title":"The self-polarization effect in Pb(Zr0.5Ti0.5)O3 films with no preferred polarization","volume":"47","author":"Lima","year":"2012","journal-title":"Mater. Res. Bull."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"958","DOI":"10.1126\/science.1207186","article-title":"Giant Piezoelectricity on Si for hyperactive MEMS","volume":"334","author":"Baek","year":"2011","journal-title":"Science"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"132903","DOI":"10.1063\/1.2716868","article-title":"Band gap and Schottky barrier heights of multiferroic BiFeO3","volume":"90","author":"Clark","year":"2007","journal-title":"Appl. Phys. Lett."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1109\/TUFFC.2014.006668","article-title":"Composition-driven structural phase transitions in rare-earth-doped BiFeO3 ceramics: A review","volume":"62","author":"Arnold","year":"2015","journal-title":"IEEE Trans. Ultrason Ferroelectr. Freq. Control"}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/14\/7\/1694\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T14:10:28Z","timestamp":1760364628000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/14\/7\/1694"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,3,30]]},"references-count":46,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2021,4]]}},"alternative-id":["ma14071694"],"URL":"https:\/\/doi.org\/10.3390\/ma14071694","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,3,30]]}}}