title: Application of Organophosphonic Acids by One-Step Supercritical CO2 on 1D and 2D Semiconductors: Toward Enhanced Electrical and Sensing Performances.
abstract: Formation of dense monolayers with proven atmospheric stability using simple fabrication conditions remains a major challenge for potential applications such as (bio)sensors, solar cells, surfaces for growth of biological cells, and molecular, organic, and plastic electronics. Here, we demonstrate a single-step modification of organophosphonic acids (OPA) on 1D and 2D structures using supercritical carbon dioxide (SCCO2) as a processing medium, with high stability and significantly shorter processing times than those obtained by the conventional physisorption-chemisorption method (2.5 h vs 48-60 h).The advantages of this approach in terms of stability and atmospheric resistivity are demonstrated on various 2D materials, such as indium-tin-oxide (ITO) and 2D Si surfaces. The advantage of the reported approach on electronic and sensing devices is demonstrated by Si nanowire field effect transistors (SiNW FETs), which have shown a few orders of magnitude higher electrical and sensing performances, compared with devices obtained by conventional approaches. The compatibility of the reported approach with various materials and its simple implementation with a single reactor makes it easily scalable for various applications.
authors.affiliation: ‡Department of Chemical and Biomolecular Engineering, National University of Singapore,4 Engineering Drive 4, Singapore 117585, Singapore.
authors.forename: Bhavesh
authors.initials: B
authors.lastname: Bhartia
authors.affiliation: §The Department of Chemical Engineering and Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel.
authors.forename: Nadav
authors.initials: N
authors.lastname: Bacher
authors.affiliation: ⊥Environmental and Water Technology Centre of Innovation, Ngee Ann Polytechnic, 535 Clementi Rd, Singapore599489, Singapore.
authors.forename: Sundaramurthy
authors.initials: S
authors.lastname: Jayaraman
authors.affiliation: §The Department of Chemical Engineering and Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel.
authors.forename: Salam
authors.initials: S
authors.lastname: Khatib
authors.affiliation: ∥Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602, Singapore.
authors.forename: Jing
authors.initials: J
authors.lastname: Song
authors.affiliation: ∥Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602, Singapore.
authors.forename: Shifeng
authors.initials: S
authors.lastname: Guo
authors.affiliation: ∥Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602, Singapore.
authors.forename: Cedric
authors.initials: C
authors.lastname: Troadec
authors.affiliation: ∥Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602, Singapore.
authors.forename: Sreenivasa Reddy
authors.initials: SR
authors.lastname: Puniredd
authors.affiliation: ‡Department of Chemical and Biomolecular Engineering, National University of Singapore,4 Engineering Drive 4, Singapore 117585, Singapore.
authors.forename: Madapusi Palavedu
authors.initials: MP
authors.lastname: Srinivasan
authors.affiliation: §The Department of Chemical Engineering and Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel.
authors.forename: Hossam
authors.initials: H
authors.lastname: Haick
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D002245:Carbon Dioxide / Q000737:chemistry*; D025924:Chromatography, Supercritical Fluid / Q000379:methods*; D003217:Conductometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008422:Materials Testing; D063065:Organophosphonates / Q000737:chemistry*; D012666:Semiconductors
chemical_list: D063065:Organophosphonates; D002245:Carbon Dioxide
keywords: modification; organophosphonic acid; sensor; silicon nanowire; supercritical carbon dioxde; volatile organic compound