{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T20:31:28Z","timestamp":1776976288382,"version":"3.51.4"},"reference-count":47,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2019,3,12]],"date-time":"2019-03-12T00:00:00Z","timestamp":1552348800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004515","name":"Universiti Kebangsaan Malaysia","doi-asserted-by":"publisher","award":["GUP-2016-063"],"award-info":[{"award-number":["GUP-2016-063"]}],"id":[{"id":"10.13039\/501100004515","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004515","name":"Universiti Kebangsaan Malaysia","doi-asserted-by":"publisher","award":["MI-2018-002"],"award-info":[{"award-number":["MI-2018-002"]}],"id":[{"id":"10.13039\/501100004515","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004515","name":"Universiti Kebangsaan Malaysia","doi-asserted-by":"publisher","award":["ST-2018-005"],"award-info":[{"award-number":["ST-2018-005"]}],"id":[{"id":"10.13039\/501100004515","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Catalysts"],"abstract":"<jats:p>Herein, we report a facile procedure to synthesize the hybrid magnetic catalyst (Ru@CS-CR@Mn) using ruthenium (Ru) supported on ionically cross-linked chitosan-carrageenan (CS-CR) and manganese ferrite (MnFe2O4) nanoparticles with excellent catalytic activity. The ionic gelation of CS-CR is acting as a protecting layer to promote the encapsulation of MnFe2O4 and Ru nanoparticles by electrostatic interactions. The presence of an active metal and a CS-CR layer on the as-prepared Ru@CS-CR@Mn catalyst was well determined by a series of physicochemical analyses. Subsequently, the catalytic performances of the Ru@CS-CR@Mn catalysts were further examined in the 4-nitrophenol (4-NP) reduction reaction in the presence of sodium borohydride (reducing agent) at ambient temperature. The Ru@CS-CR@Mn catalyst performed excellent catalytic activity in the 4-NP reduction, with a turnover frequency (TOF) values of 925 h\u22121 and rate constant (k) of 0.078 s\u22121. It is worth to mentioning that the Ru@CS-CR@Mn catalyst can be recycled and reused up to at least ten consecutive cycles in the 4-NP reduction with consistency in catalytic performance. The Ru@CS-CR@Mn catalyst is particularly attractive as a catalyst due to its superior catalytic activity and superparamagnetic properties for easy separation. We foresee this catalyst having high potential to be extended in a wide range of chemistry applications.<\/jats:p>","DOI":"10.3390\/catal9030254","type":"journal-article","created":{"date-parts":[[2019,3,13]],"date-time":"2019-03-13T04:07:37Z","timestamp":1552450057000},"page":"254","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Ruthenium Supported on Ionically Cross-linked Chitosan-Carrageenan Hybrid MnFe2O4 Catalysts for 4-Nitrophenol Reduction"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2444-3677","authenticated-orcid":false,"given":"Kin Hong","family":"Liew","sequence":"first","affiliation":[{"name":"School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi 43600 UKM, Selangor Darul Ehsan, Malaysia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9490-4451","authenticated-orcid":false,"given":"Tian Khoon","family":"Lee","sequence":"additional","affiliation":[{"name":"Fuell cell Institute (FCI), Universiti Kebangsaan Malaysia, Bangi 43600 UKM, Selangor Darul Ehsan, Malaysia"}]},{"given":"Mohd Ambar","family":"Yarmo","sequence":"additional","affiliation":[{"name":"School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi 43600 UKM, Selangor Darul Ehsan, Malaysia"}]},{"given":"Kee Shyuan","family":"Loh","sequence":"additional","affiliation":[{"name":"Fuell cell Institute (FCI), Universiti Kebangsaan Malaysia, Bangi 43600 UKM, Selangor Darul Ehsan, Malaysia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1176-9064","authenticated-orcid":false,"given":"Andreia F.","family":"Peixoto","sequence":"additional","affiliation":[{"name":"REQUIMTE-LAQV, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1753-8678","authenticated-orcid":false,"given":"Cristina","family":"Freire","sequence":"additional","affiliation":[{"name":"REQUIMTE-LAQV, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"given":"Rahimi M.","family":"Yusop","sequence":"additional","affiliation":[{"name":"School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi 43600 UKM, Selangor Darul Ehsan, Malaysia"},{"name":"Kluster Perubatan Regeneratif, Institut Perubatan dan Pergigian Termaju, Universiti Sains Malaysia, Bertam Kepala Batas 13200, Pulau Pinang, Malaysia"}]}],"member":"1968","published-online":{"date-parts":[[2019,3,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"317","DOI":"10.1016\/j.apcatb.2011.04.025","article-title":"Metal-free-photocatalytic reduction of 4-nitrophenol by resin-supported dye under the visible irradiation","volume":"105","author":"Gazi","year":"2011","journal-title":"Appl. Catal. B"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"19696","DOI":"10.1039\/C4TA04919E","article-title":"Palladium nanoparticles immobilized on core\u2013shell magnetic fibers as a highly efficient and recyclable heterogeneous catalyst for the reduction of 4-nitrophenol and Suzuki coupling reactions","volume":"2","author":"Le","year":"2014","journal-title":"J. Mater. Chem. A"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"4117","DOI":"10.1016\/j.watres.2008.07.009","article-title":"p-Nitrophenol removal by combination of powdered activated carbon adsorption and ultrafiltration-comparison of different operational modes","volume":"42","author":"Hobby","year":"2008","journal-title":"Water Res."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"192","DOI":"10.3389\/fchem.2018.00192","article-title":"Photocatalytic degradation of 4-nitrophenol by C, N-TiO2: Degradation efficiency vs. embryonic toxicity of the resulting compounds","volume":"6","author":"Osin","year":"2018","journal-title":"Front. Chem."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"78","DOI":"10.1016\/j.colsurfa.2014.10.020","article-title":"Adsorption of p-nitrophenol from aqueous solutions using nanographite oxide","volume":"464","author":"Zhang","year":"2015","journal-title":"Colloids Surf. A"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"6480","DOI":"10.1021\/acs.iecr.5b01010","article-title":"In situ synthesis of monodisperse silver nanoparticles on sulfhydryl-functionalized poly(glycidyl methacrylate) microspheres for catalytic reduction of 4-nitrophenol","volume":"54","author":"Zhang","year":"2015","journal-title":"Ind. Eng. Chem. Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2123","DOI":"10.1007\/s10876-017-1207-z","article-title":"Strategic green synthesis, characterization and catalytic application to 4-nitrophenol reduction of palladium nanoparticles","volume":"28","author":"Gopalakrishnan","year":"2017","journal-title":"J. Clust. Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1626","DOI":"10.1007\/s10562-015-1547-y","article-title":"Catalytic reduction of p-nitrophenol using chitosan stabilized copper nanoparticles","volume":"145","author":"Tan","year":"2015","journal-title":"Catal. Lett."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"16071","DOI":"10.1021\/am503913y","article-title":"Multiply twinned AgNi alloy nanoparticles as highly active catalyst for multiple reduction and degradation reactions","volume":"6","author":"Kumar","year":"2014","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"9410","DOI":"10.1039\/C5CC01131K","article-title":"Nitroarene reduction: A trusted model reaction to test nanoparticle catalysts","volume":"51","author":"Aditya","year":"2015","journal-title":"Chem. Comm."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"656","DOI":"10.1016\/j.jscs.2015.11.001","article-title":"Starch-supported gold nanoparticles and their use in 4-nitrophenol reduction","volume":"21","author":"Chairam","year":"2017","journal-title":"J. Saudi Chem. Soc."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1016\/j.jcis.2018.12.053","article-title":"One-pot green synthesis of bimetallic hollow palladium-platinum nanotubes for enhanced catalytic reduction of p-nitrophenol","volume":"539","author":"Wang","year":"2019","journal-title":"J Colloid Interface Sci."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"3783","DOI":"10.1039\/C8TA11604K","article-title":"Plasmonic Ru\/hydrogen molybdenum bronzes with tunable oxygen vacancies for light-driven reduction of p-nitrophenol","volume":"7","author":"Yin","year":"2019","journal-title":"J. Mater. Chem. A"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1016\/j.chemosphere.2016.12.103","article-title":"Anchoring of silver nanoparticles on graphitic carbon nitride sheets for the synergistic catalytic reduction of 4-nitrophenol","volume":"172","author":"Wang","year":"2017","journal-title":"Chemosphere"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"3188","DOI":"10.1039\/C5SC04714E","article-title":"Unprotected and interconnected Ru0 nano-chain networks: Advantages of unprotected surfaces in catalysis and electrocatalysis","volume":"7","author":"Anantharaj","year":"2016","journal-title":"Chem. Sci."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"3091","DOI":"10.1002\/anie.201511305","article-title":"Highly efficient transition metal nanoparticle catalysts in aqueous solutions","volume":"55","author":"Wang","year":"2016","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"402","DOI":"10.1039\/C7NJ03753H","article-title":"Preparation of metal oxide supported catalysts and their utilization for understanding the effect of a support on the catalytic activity","volume":"42","author":"Seth","year":"2018","journal-title":"New J. Chem."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"23448","DOI":"10.1039\/C5TA06875D","article-title":"Highly stable ruthenium nanoparticles on 3D mesoporous carbon: An excellent opportunity for the reduction reactions\u2020","volume":"3","author":"Kumar","year":"2015","journal-title":"J. Mater. Chem. A"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1110","DOI":"10.1007\/s10562-018-2313-8","article-title":"Ruthenium nanoparticles immobilized on nano-silica functionalized with thiol-based dendrimer: A nanocomposite material for oxidation of alcohols and epoxidation of alkenes","volume":"148","author":"Kashani","year":"2018","journal-title":"Catal. Lett."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Zheng, K., Shen, C., Qiao, J., Tong, J., Jin, J., and Zhang, P. (2018). Novel magnetically-recyclable, nitrogen-doped Fe3O4@Pd NPs for Suzuki\u2013Miyaura coupling and their application in the synthesis of crizotinib. Catalysts, 8.","DOI":"10.3390\/catal8100443"},{"key":"ref_21","first-page":"178","article-title":"Applications of iron oxide nano composite in waste water treatment\u2013dye decolourisation and anti\u2012microbial activity","volume":"2","author":"Subha","year":"2018","journal-title":"MOJ Drug Des. Develop. Ther."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1186\/s11671-018-2580-8","article-title":"A hydrothermal synthesis of Fe3O4@C hybrid nanoparticle and magnetic adsorptive performance to remove heavy metal ions in aqueous solution","volume":"13","author":"Ji","year":"2018","journal-title":"Nanoscale Res. Lett."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Jia, L., Zhang, W., Xu, J., Cao, J., Xu, Z., and Wang, Y. (2018). Facile fabrication of highly active magnetic aminoclay supported palladium nanoparticles for the room temperature catalytic reduction of nitrophenol and nitroanilines. Nanomaterials, 8.","DOI":"10.3390\/nano8060409"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"12231","DOI":"10.1007\/s10854-018-9334-3","article-title":"MWCNT decorated MnFe2O4 nanoparticles as an efficient photo-catalyst for phenol degradation","volume":"29","author":"Hazarika","year":"2018","journal-title":"J. Mater. Sci. Mater. Electron."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1222","DOI":"10.1002\/anie.200602866","article-title":"Magnetic nanoparticles: Synthesis, protection, functionalization, and application","volume":"46","author":"Lu","year":"2007","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2092","DOI":"10.1080\/19443994.2014.958538","article-title":"Effective removal of As(III) from drinking water samples by chitosan-coated magnetic nanoparticles","volume":"56","author":"Abdollahia","year":"2015","journal-title":"Desalination Water Treat."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1016\/j.progpolymsci.2004.12.001","article-title":"Heterogeneous catalysis on chitosan-based materials: A review","volume":"30","author":"Guibal","year":"2005","journal-title":"Prog. Polym. Sci."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1016\/j.jiec.2015.01.023","article-title":"Magnetic chitosan composite for adsorption of cationic and anionic dyes in aqueous solution","volume":"28","author":"Cho","year":"2015","journal-title":"J. Ind. Eng. Chem."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"302","DOI":"10.1186\/s11671-015-0916-1","article-title":"Green sonochemical synthesis of silver nanoparticles at varying concentrations of \u03ba-carrageenan","volume":"10","author":"Elsupikhe","year":"2015","journal-title":"Nanoscale Res. Lett."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1496","DOI":"10.1021\/cm300301c","article-title":"Superparamagnetic MFe2O4 (M = Fe, Co, Mn) nanoparticles: Tuning the particle size and magnetic properties through a novel one-step coprecipitation route","volume":"24","author":"Pereira","year":"2012","journal-title":"Chem. Mater."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"3930","DOI":"10.1002\/cctc.201700649","article-title":"Highly active ruthenium supported on magnetically recyclable chitosan-based nanocatalyst for nitroarenes reduction","volume":"9","author":"Liew","year":"2017","journal-title":"ChemCatChem"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1265","DOI":"10.1002\/jbm.a.32466","article-title":"Development of new chitosan\/carrageenan nanoparticles for drug delivery applications","volume":"92","author":"Grenha","year":"2010","journal-title":"J. Biomed. Mater. Res. A"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Li, C., Hein, S., and Wang, K. (2013). Chitosan-carrageenan polyelectrolyte complex for the 512 delivery of protein drugs. Biomaterials.","DOI":"10.5402\/2013\/629807"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1071\/SR06083","article-title":"The prediction of soil carbon fractions using mid-infrared-partial least square analysis","volume":"45","author":"Janik","year":"2007","journal-title":"Aust. J. Soil. Res."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"2122","DOI":"10.1039\/c3gc42004c","article-title":"Ruthenium on chitosan: A recyclable heterogeneous catalyst for aqueous hydration of nitriles to amides","volume":"16","author":"Baig","year":"2014","journal-title":"Green Chem."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"D\u00edaz-Hern\u00e1ndez, A., Gracida, J., Garc\u00eda-Almend\u00e1rez, B.E., Regalado, C., N\u00fa\u00f1ez, R., and Amaro-Reyes, A. (2018). Characterization of magnetic nanoparticles coated with chitosan: A potential approach for enzyme immobilization. J. Nanomater.","DOI":"10.1155\/2018\/9468574"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"107101","DOI":"10.1088\/1674-1056\/22\/10\/107101","article-title":"Growth of monodisperse nanospheres of MnFe2O4 with enhanced magnetic and optical properties","volume":"22","author":"Rafique","year":"2013","journal-title":"Chin. Phys. B"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"5131","DOI":"10.1039\/C4RA15865B","article-title":"Gold-supported magnetically recyclable nanocatalysts: A sustainable solution for the reduction of 4-nitrophenol in water","volume":"5","author":"Rocha","year":"2015","journal-title":"RSC Adv."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"5436","DOI":"10.1039\/c0jm00456a","article-title":"Controllable incorporation of Ag and Ag\u2013Au nanoparticles in carbon spheres for tunable optical and catalytic properties","volume":"20","author":"Tang","year":"2010","journal-title":"J. Mater. Chem."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"27526","DOI":"10.1039\/C4RA16792A","article-title":"PdO nanoparticles enhancing the catalytic activity of Pd\/carbon nanotubes for 4-nitrophenol reduction","volume":"5","author":"Wang","year":"2015","journal-title":"RSC Adv."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"23230","DOI":"10.1039\/C5TA05092H","article-title":"Polymer-templated synthesis of hollow Pd-CeO2 nanocomposite spheres and their catalytic activity and thermal stability","volume":"3","author":"Du","year":"2015","journal-title":"J. Mater. Chem. A"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"2885","DOI":"10.1021\/la902950x","article-title":"Photochemical green synthesis of calcium-alginate-stabilized Ag and Au nanoparticles and their catalytic application to 4-nitrophenol reduction","volume":"26","author":"Saha","year":"2010","journal-title":"Langmuir"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"6609","DOI":"10.1039\/C4NR00826J","article-title":"Covalently functionalized carbon nanotube supported Pd nanoparticles for catalytic reduction of 4-nitrophenol","volume":"6","author":"Gu","year":"2014","journal-title":"Nanoscale"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"16425","DOI":"10.1039\/C4RA01866D","article-title":"Reduction of 4-nitrophenol catalyzed by silver nanoparticles supported on polymer micelles and vesicles","volume":"4","author":"Geng","year":"2014","journal-title":"RSC Adv."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"2692","DOI":"10.1039\/C8DT04663H","article-title":"Ordered mesoporous silica cubic decorated with silver nanoparticles: A highly active and recyclable heterogeneous catalyst for the reduction of 4-nitrophenol","volume":"48","author":"Fan","year":"2019","journal-title":"Dalton Trans."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"5553","DOI":"10.1021\/acscatal.6b00635","article-title":"The Impact of Gold Nanoparticle Stabilizing Ligand on Colloidal Catalytic Reduction of 4-Nitrophenol","volume":"6","author":"Ansar","year":"2016","journal-title":"ACS Catal."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1002\/(SICI)1097-4628(19970103)63:1<125::AID-APP13>3.0.CO;2-4","article-title":"Novel hydrophilic chitosan-polyethylene oxide nanoparticles as protein carriers","volume":"63","author":"Calvo","year":"1997","journal-title":"J. Appl. Polym. Sci."}],"container-title":["Catalysts"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4344\/9\/3\/254\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T12:38:19Z","timestamp":1760186299000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4344\/9\/3\/254"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,3,12]]},"references-count":47,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2019,3]]}},"alternative-id":["catal9030254"],"URL":"https:\/\/doi.org\/10.3390\/catal9030254","relation":{},"ISSN":["2073-4344"],"issn-type":[{"value":"2073-4344","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,3,12]]}}}