{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T04:58:56Z","timestamp":1790398736285,"version":"4.1.0"},"reference-count":39,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T00:00:00Z","timestamp":1790121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22266032, 22566032"],"award-info":[{"award-number":["22266032, 22566032"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["22266032, 22566032"],"award-info":[{"award-number":["22266032, 22566032"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Science and Technology projects of Xizang Autonomous Region","award":["XZ202501ZY0072, XZ202501ZY0008 and XZ202601ZR0023"],"award-info":[{"award-number":["XZ202501ZY0072, XZ202501ZY0008 and XZ202601ZR0023"]}]},{"name":"the Lhasa Municipal Major Science and Technology Project","award":["LSKJ202543"],"award-info":[{"award-number":["LSKJ202543"]}]},{"name":"the Talent Incentive Program for Young Scholars of Xizang University","award":["ZDRC202410"],"award-info":[{"award-number":["ZDRC202410"]}]},{"name":"the High-Level Talent Cultivation Pro-gram for Postgraduates of Xizang University","award":["2026-GSP-B021"],"award-info":[{"award-number":["2026-GSP-B021"]}]},{"name":"Central Financial Support Special Funds for Local Colleges and Universities","award":["[2025]01 and [2026]44"],"award-info":[{"award-number":["[2025]01 and [2026]44"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Fluoride contamination in geothermal water is a persistent water-quality concern in high-altitude regions, particularly on the Qinghai\u2013Tibet Plateau. In this study, lightweight magnesium oxide (MgO) nanosheets were investigated for fluoride adsorption from geothermal water, with emphasis on adsorption performance and the underlying mechanism. The effects of MgO dosage, temperature, contact time, and initial fluoride concentration were systematically evaluated, while the physicochemical changes of MgO before and after fluoride adsorption were characterized using SEM, EDS, HRTEM, BET, FTIR, and XPS. The MgO nanosheets exhibited abundant surface hydroxyl groups and enabled rapid fluoride uptake under elevated-temperature conditions. At 70 \u00b0C and an MgO dosage of 3 g\/L, more than 95% of fluoride was adsorbed within 10 min. The saturated adsorption capacity was 87.167 mg\/g at an initial fluoride concentration of 500 mg\/L. Kinetic analysis revealed rapid initial uptake followed by a slower adsorption stage, with intraparticle diffusion contributing to, but not solely controlling, the overall adsorption process. The equilibrium data were better described by the Langmuir model than by the Freundlich model (R2 = 0.940 vs. 0.725), suggesting relatively homogeneous surface sites. FTIR and XPS analyses revealed pronounced changes in the surface chemical environment following water contact and fluoride adsorption. These changes suggest that water-induced hydration and hydroxylation generate reactive Mg\u2013OH sites, which subsequently interact with fluoride through hydroxyl\u2013fluoride exchange and the formation of Mg\u2013F-related surface species. These findings highlight the contribution of surface chemical interactions to fluoride uptake by MgO nanosheets and their potential for rapid fluoride control in geothermal water.<\/jats:p>","DOI":"10.3390\/molecules31193387","type":"journal-article","created":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T14:03:26Z","timestamp":1790172206000},"page":"3387","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Light Magnesium Oxide Nanosheets for Efficient Fluoride Removal from Geothermal Water: Rapid Adsorption and Mechanistic Insights"],"prefix":"10.3390","volume":"31","author":[{"given":"Junli","family":"Chen","sequence":"first","affiliation":[{"name":"Key Laboratory of Biodiversity and Environment on the Qinghai-Tibet Plateau, Ministry of Education, School of Ecology and Environment, Xizang University, Lhasa 850000, China"},{"name":"Analysis and Testing Center, Xizang University, Lhasa 850000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fangjing","family":"Xiao","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biodiversity and Environment on the Qinghai-Tibet Plateau, Ministry of Education, School of Ecology and Environment, Xizang University, Lhasa 850000, China"},{"name":"Analysis and Testing Center, Xizang University, Lhasa 850000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaomei","family":"Cui","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biodiversity and Environment on the Qinghai-Tibet Plateau, Ministry of Education, School of Ecology and Environment, Xizang University, Lhasa 850000, China"},{"name":"Analysis and Testing Center, Xizang University, Lhasa 850000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8755-9672","authenticated-orcid":false,"given":"Duo","family":"Bu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biodiversity and Environment on the Qinghai-Tibet Plateau, Ministry of Education, School of Ecology and Environment, Xizang University, Lhasa 850000, China"},{"name":"Analysis and Testing Center, Xizang University, Lhasa 850000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianjie","family":"Fu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiangying","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biodiversity and Environment on the Qinghai-Tibet Plateau, Ministry of Education, School of Ecology and Environment, Xizang University, Lhasa 850000, China"},{"name":"Analysis and Testing Center, Xizang University, Lhasa 850000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"330","DOI":"10.1038\/ngeo1449","article-title":"Penetration of crustal melt beyond the Kunlun Fault into northern Tibet","volume":"5","author":"Jones","year":"2012","journal-title":"Nat. Geosci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"102413","DOI":"10.1016\/j.gsf.2026.102413","article-title":"Genesis of multi-source mixed geothermal fluids in the eastern Tibetan Plateau","volume":"17","author":"Zhang","year":"2026","journal-title":"Geosci. Front."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"107640","DOI":"10.1016\/j.gexplo.2024.107640","article-title":"Fluoride in geothermal water: Occurrence, origin, migration and environmental impact","volume":"270","author":"Huang","year":"2025","journal-title":"J. Geochem. Explor."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"207","DOI":"10.1007\/s42452-024-05798-1","article-title":"Arsenic in the Tibetan Plateau\u2019s geothermal systems: A detailed analysis of forms, sources, and geochemical behaviors","volume":"6","author":"Shi","year":"2024","journal-title":"Discov. Appl. Sci."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"125797","DOI":"10.1016\/j.chemer.2021.125797","article-title":"Origin of the enrichment of B and alkali metal elements in the geothermal water in the Tibetan Plateau: Evidence from B and Sr isotopes","volume":"81","author":"Elenga","year":"2021","journal-title":"Geochemistry"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"107748","DOI":"10.1016\/j.cclet.2022.107748","article-title":"Effectively arsenic (V) and fluoride removal in geothermal water using magnetic Fe3O4@MgO nanoparticles","volume":"34","author":"Zhang","year":"2023","journal-title":"Chin. Chem. Lett."},{"key":"ref_7","first-page":"487","article-title":"Concentrations and sources of arsenic and fluoride in high-temperature geothermal water from Yangbajing, Xizang","volume":"43","author":"Xu","year":"2024","journal-title":"Rock Miner. Anal."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"133510","DOI":"10.1016\/j.jhazmat.2024.133510","article-title":"Hotspot mapping and risk prediction of fluoride in natural waters across the Tibetan Plateau","volume":"465","author":"Yang","year":"2024","journal-title":"J. Hazard. Mater."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1080\/10408444.2023.2295338","article-title":"Systematic review of epidemiological and toxicological evidence on health effects of fluoride in drinking water","volume":"54","author":"Taher","year":"2024","journal-title":"Crit. Rev. Toxicol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1016\/j.neuroscience.2024.08.011","article-title":"Focus on cognitive impairment induced by excessive fluoride: An update review","volume":"558","author":"Zhang","year":"2024","journal-title":"Neuroscience"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"735","DOI":"10.1016\/j.jobcr.2024.10.002","article-title":"Fluoride effect on renal and hepatic functions: A comprehensive decade review of in vitro and in vivo studies","volume":"14","author":"Lavanya","year":"2024","journal-title":"J. Oral Biol. Craniofac. Res."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1016\/j.jes.2025.11.010","article-title":"Environmental fluoride exposure and bone metabolism: Molecular pathways and health implications","volume":"166","author":"Chang","year":"2025","journal-title":"J. Environ. Sci."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1016\/S0022-1139(00)00310-9","article-title":"Fluoride in the environment and brick-tea-type fluorosis in Tibet","volume":"106","author":"Cao","year":"2000","journal-title":"J. Fluor. Chem."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"110802","DOI":"10.1016\/j.cep.2026.110802","article-title":"Fluoride removal by precipitation-coagulation in high gravity reactors","volume":"225","author":"Pardey","year":"2026","journal-title":"Chem. Eng. Process. Process Intensif."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"117653","DOI":"10.1016\/j.jece.2025.117653","article-title":"Induced crystallization techniques for fluoride removal from wastewater: Current developments and applications","volume":"13","author":"Gao","year":"2025","journal-title":"J. Environ. Chem. Eng."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"150880","DOI":"10.1016\/j.cej.2024.150880","article-title":"Membrane-based removal of fluoride from groundwater","volume":"488","author":"Rathi","year":"2024","journal-title":"Chem. Eng. J."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"122564","DOI":"10.1016\/j.jenvman.2024.122564","article-title":"Bibliometric analysis and systematic review of fluoride-containing wastewater treatment: Development, hotspots and future perspectives","volume":"370","author":"Du","year":"2024","journal-title":"J. Environ. Manag."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"108256","DOI":"10.1016\/j.jwpe.2025.108256","article-title":"A robust approach for sustainable removal and recovery of fluoride via cryolite crystallization in an enhanced electrocoagulation process","volume":"76","author":"Nguyen","year":"2025","journal-title":"J. Water Process Eng."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"119362","DOI":"10.1016\/j.ecoenv.2025.119362","article-title":"Rapid and synergistic adsorption of arsenic and fluoride by bifunctional Al\/Ce oxides in complex geothermal matrices","volume":"306","author":"Xiao","year":"2025","journal-title":"Ecotoxicol. Environ. Saf."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"172921","DOI":"10.1016\/j.cej.2026.172921","article-title":"Unlocking internal aluminum reactivity in nanohydrated alumina via amyloid fibril nanoconfinement for highly efficient water defluorination","volume":"529","author":"Zhao","year":"2026","journal-title":"Chem. Eng. J."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"104563","DOI":"10.1016\/j.jece.2020.104563","article-title":"Design and development of amine functionalized iron based metal organic frameworks for selective fluoride removal from water environment","volume":"9","author":"Jeyaseelan","year":"2021","journal-title":"J. Environ. Chem. Eng."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"103091","DOI":"10.1016\/j.jwpe.2022.103091","article-title":"Improved remediation of fluoride contaminated water using titania-alumina sorbents","volume":"49","author":"Colledge","year":"2022","journal-title":"J. Water Process Eng."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"20826","DOI":"10.1021\/acsomega.5c13052","article-title":"Efficient fluoride removal by Ce-MOFs and Ce\/Mg MOFs: A mechanistic investigation","volume":"11","author":"Lu","year":"2026","journal-title":"ACS Omega"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"02636174261418492","DOI":"10.1177\/02636174261418492","article-title":"Enhanced fixed-bed column adsorption using a ternary MgO-impregnated eggshell-kaolin composite: Toward an efficient and sustainable fluoride removal technology","volume":"44","author":"Kitemangu","year":"2026","journal-title":"Adsorpt. Sci. Technol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"109158","DOI":"10.1016\/j.jwpe.2025.109158","article-title":"Fluoride removal by MgO-based adsorbents synthesized via distinct routes: Comparative evaluation of adsorption efficiency and column-scale stability","volume":"80","author":"Chan","year":"2025","journal-title":"J. Water Process Eng."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"357","DOI":"10.1007\/s10653-026-03237-1","article-title":"A novel composite of Mg-Al layered double hydroxide\/aeolian sand for enhanced removal of fluoride from water","volume":"48","author":"Li","year":"2026","journal-title":"Environ. Geochem. Health"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Wang, D.C., Xu, M.D., Jin, Z., Xiao, Y.F., Chao, Y., Li, J., Chen, S., and Ding, Y. (2023). Synthesis and characterization of porous MgO nanosheet-modified activated carbon fiber felt for fluoride adsorption. Nanomaterials, 13.","DOI":"10.3390\/nano13061082"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"163053","DOI":"10.1016\/j.cej.2025.163053","article-title":"Interfacial hydration of zeolite-confined MgO for enhanced fluoride removal from water","volume":"513","author":"Yu","year":"2025","journal-title":"Chem. Eng. J."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"5815996","DOI":"10.1155\/2022\/5815996","article-title":"Hydrogeochemical characteristics and genesis of the Chazi geothermal field area in Tibet","volume":"2022","author":"Song","year":"2022","journal-title":"Geofluids"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"24786","DOI":"10.1039\/D2RA02636H","article-title":"Enhanced adsorptive removal of indigo carmine dye by bismuth oxide doped MgO based adsorbents from aqueous solution: Equilibrium, kinetic and computational studies","volume":"12","author":"Adam","year":"2022","journal-title":"RSC Adv."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0021-9517(02)93741-3","article-title":"Hydroxyl groups on \u03b3-alumina surfaces: A DFT study","volume":"211","author":"Digne","year":"2002","journal-title":"J. Catal."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"24292","DOI":"10.1039\/D1RA04290D","article-title":"Fourier-transform infrared and X-ray diffraction analyses of the hydration reaction of pure magnesium oxide and chemically modified magnesium oxide","volume":"11","author":"Kurosawa","year":"2021","journal-title":"RSC Adv."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1707","DOI":"10.1039\/C8QM00145F","article-title":"Are organic templates responsible for the optical and magnetic response of MgO nanoparticles?","volume":"2","author":"Singh","year":"2018","journal-title":"Mater. Chem. Front."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"28196","DOI":"10.1039\/D2RA04907D","article-title":"Anticorrosion behaviour and tribological properties of AZ31 magnesium alloy coated with Nb2O5\/Nb2O5\u2013Mg\/Mg layer by magnetron sputtering","volume":"12","author":"Ding","year":"2022","journal-title":"RSC Adv."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"8912","DOI":"10.1038\/s41467-025-63980-4","article-title":"Self-powered near-infrared mechanoluminescence through MgO\/MgF2 piezo-photonic heterojunctions","volume":"16","author":"Wu","year":"2025","journal-title":"Nat. Commun."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1815397","DOI":"10.1155\/gfl\/1815397","article-title":"Hydrochemical characteristics of high-temperature geothermal fluids and quantitative assessment of wellbore scaling in the Yangbajain geothermal field, Tibet","volume":"2026","author":"Li","year":"2026","journal-title":"Geofluids"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Yang, H., Yuan, X., Chen, Y., Liu, J., Zhan, C., Lv, G., Hu, J., Sun, M., and Zhang, Y. (2023). Geochemical evidence constraining genesis and mineral scaling of the Yangbajing geothermal field, Southwestern China. Water, 16.","DOI":"10.3390\/w16010024"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"121416","DOI":"10.1016\/j.molliq.2023.121416","article-title":"On validity, physical meaning, mechanism insights and regression of adsorption kinetic models","volume":"376","author":"Vareda","year":"2023","journal-title":"J. Mol. Liq."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1007\/s13201-025-02682-0","article-title":"Review of adsorption isotherms models","volume":"16","author":"Danat","year":"2026","journal-title":"Appl. Water Sci."}],"container-title":["Molecules"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1420-3049\/31\/19\/3387\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T04:10:30Z","timestamp":1790395830000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1420-3049\/31\/19\/3387"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,23]]},"references-count":39,"journal-issue":{"issue":"19","published-online":{"date-parts":[[2026,10]]}},"alternative-id":["molecules31193387"],"URL":"https:\/\/doi.org\/10.3390\/molecules31193387","relation":{},"ISSN":["1420-3049"],"issn-type":[{"value":"1420-3049","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,23]]}}}