@article{scholars13340,
         journal = {Applied Surface Science},
            year = {2020},
       publisher = {Elsevier B.V.},
             doi = {10.1016/j.apsusc.2019.144978},
            note = {cited By 14},
          volume = {506},
           title = {Investigation on particle properties and extent of functionalization of silica nanoparticles},
        abstract = {Quantification of the extent of functionalization on silica nanoparticle surface is crucial in a variety of applications. This work aims to evaluate particle properties and extent of functionalization on silica nanoparticles synthesized under acidic and basic conditions via co-condensation of tetraethyl orthosilicate with 3-aminopropyltrimethoxysilane in the sol-gel process. The silica nanoparticles properties were analyzed via field emission scanning electron microscope, transmission electron microscopy, dynamic light scattering, and Brunauer-Emmett-Teller methods; whereas, the extent of functionalization was evaluated using Fourier transform infrared spectroscopy, X-ray photoelectron spectrometer, and thermogravimetric analyzer. Results showed that the functionalized silica nanoparticles have a lower tendency to agglomerate and highly monodispersed as compared to unfunctionalized. The surface areas of acid and base-catalyzed nanoparticles were obtained as 618.8 and 514.7 m2/g, respectively. FTIR spectra, XPS scans, and TGA curves confirmed the presence of alkyl and amine functional groups on the functionalized surfaces. The extent of functionalization (N/Si) was obtained as 0.296 and 0.196, and the percentages of functional groups attached on the surface were found to be 6.80 and 5.92 for acid and base-catalyzed nanoparticles, respectively. The overall results suggest that acidic catalysis is a better approach for the synthesis of surface-modified or organofunctionalized silica nanoparticles. {\^A}{\copyright} 2019 Elsevier B.V.},
             url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85076474092&doi=10.1016\%2fj.apsusc.2019.144978&partnerID=40&md5=a60051413d9839b0fcdae20b6465f7f2},
            issn = {01694332},
        keywords = {Catalysis; Condensation; Fourier transform infrared spectroscopy; High resolution transmission electron microscopy; Light scattering; Nanoparticles; Scanning electron microscopy; Silica; Sol-gel process; Spectrometers; Synthesis (chemical), 3-aminopropyl trimethoxysilane; Brunauer-Emmett-Teller method; Co-condensation; Field emission scanning electron microscopes; Functionalizations; Organofunctionalized silicas; Particle properties; Thermogravimetric analyzers, Silica nanoparticles},
          author = {Idris, A. and Man, Z. and Maulud, A. S. and Bustam, M. A. and Mannan, H. A. and Ahmed, I.}
}