{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,30]],"date-time":"2025-11-30T22:35:24Z","timestamp":1764542124943,"version":"build-2065373602"},"reference-count":52,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,3,15]],"date-time":"2021-03-15T00:00:00Z","timestamp":1615766400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Reduced graphene oxide (rGO) is a promising graphene-based material, with transversal applicability to a wide range of technological fields. Nevertheless, the common use of efficient\u2014but hazardous to environment and toxic\u2014reducing agents prevents its application in biological and other fields. Consequently, the development of green reducing strategies is a requirement to overcome this issue. Herein, a green, simple, and cost-effective one-step reduction methodology is presented. Graphene oxide (GO) was hydrothermally reduced in the presence of caffeic acid (CA), a natural occurring phenolic compound. The improvement of the hydrothermal reduction through the presence of CA is confirmed by XRD, Raman, XPS and TGA analysis. Moreover, CA polymerizes under hydrothermal conditions with the formation of spherical and non-spherical carbon particles, which can be useful for further rGO functionalization. FTIR and XPS confirm the oxygen removal in the reduced samples. The high-resolution scanning transmission electron microscopy (HRSTEM) images also support the reduction, showing rGO samples with an ordered graphitic layered structure. The promising rGO synthesized by this eco-friendly methodology can be explored for many applications.<\/jats:p>","DOI":"10.3390\/nano11030732","type":"journal-article","created":{"date-parts":[[2021,3,15]],"date-time":"2021-03-15T11:38:58Z","timestamp":1615808338000},"page":"732","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Joining Caffeic Acid and Hydrothermal Treatment to Produce Environmentally Benign Highly Reduced Graphene Oxide"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2499-6506","authenticated-orcid":false,"given":"Ana","family":"Barra","sequence":"first","affiliation":[{"name":"Department of Materials and Ceramic Engineering, CICECO\u2014Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Department of Chemistry, CICECO\u2014Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Materials Science Institute of Madrid, CSIC, c\/Sor Juana In\u00e9s de la Cruz 3, 28049 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3712-6729","authenticated-orcid":false,"given":"Oana","family":"Laz\u0103r","sequence":"additional","affiliation":[{"name":"Center for Surface Science and Nanotechnology, University Politehnica of Bucharest, 060042 Bucharest, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4676-6568","authenticated-orcid":false,"given":"Aida","family":"Pantazi","sequence":"additional","affiliation":[{"name":"Center for Surface Science and Nanotechnology, University Politehnica of Bucharest, 060042 Bucharest, Romania"},{"name":"S.C. NANOPRO START M.C. S.R.L., 110310 Pite\u0219ti, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3555-8218","authenticated-orcid":false,"given":"Mar\u00eda J.","family":"Hortig\u00fcela","sequence":"additional","affiliation":[{"name":"Centre for Mechanical Technology &amp; Automation, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3214-8002","authenticated-orcid":false,"given":"Gonzalo","family":"Otero-Irurueta","sequence":"additional","affiliation":[{"name":"Centre for Mechanical Technology &amp; Automation, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8451-8231","authenticated-orcid":false,"given":"Marius","family":"En\u0103chescu","sequence":"additional","affiliation":[{"name":"Center for Surface Science and Nanotechnology, University Politehnica of Bucharest, 060042 Bucharest, Romania"},{"name":"Academy of Romanian Scientists, 50085 Bucharest, Romania"}]},{"given":"Eduardo","family":"Ruiz-Hitzky","sequence":"additional","affiliation":[{"name":"Materials Science Institute of Madrid, CSIC, c\/Sor Juana In\u00e9s de la Cruz 3, 28049 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7217-2790","authenticated-orcid":false,"given":"Cl\u00e1udia","family":"Nunes","sequence":"additional","affiliation":[{"name":"Department of Chemistry, CICECO\u2014Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6578-8164","authenticated-orcid":false,"given":"Paula","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramic Engineering, CICECO\u2014Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1497","DOI":"10.1021\/nl404719n","article-title":"Thermal properties of graphene-copper-graphene heterogeneous films","volume":"14","author":"Goli","year":"2014","journal-title":"Nano Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"111345","DOI":"10.1039\/C6RA24588A","article-title":"Optical advantages of graphene on the boron nitride in visible and SW-NIR regions","volume":"6","author":"Wang","year":"2016","journal-title":"RSC Adv."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1038\/ncomms4186","article-title":"Effect of defects on the intrinsic strength and stiffness of graphene","volume":"5","author":"Zandiatashbar","year":"2014","journal-title":"Nat. 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