Tapioca starch: An efficient fuel in gel-combustion synthesis of photocatalytically and anti-microbially active ZnO nanoparticles

• Published in: Materials characterization 2015-01, Vol.99, p.266-276
• Main Authors: Ramasami, Alamelu K., Raja Naika, H., Nagabhushana, H., Ramakrishnappa, T., Balakrishna, Geetha R., Nagaraju, G.
• Format: Article
• Language: English
• Subjects: ABSORPTION; AGAR; Anti-bacterial activity; Antibacterial properties; Bacteria; CRYSTAL STRUCTURE; DIFFUSION; ESCHERICHIA COLI; FOURIER TRANSFORMATION; Gel-synthesis; INFRARED SPECTRA; KLEBSIELLA; Klebsiella aerogenes; Manihot esculenta; NANOPARTICLES; NANOSCIENCE AND NANOTECHNOLOGY; PHOTOCATALYSIS; POROUS MATERIALS; PSEUDOMONAS; Pseudomonas aeruginosa; SCANNING ELECTRON MICROSCOPY; STAPHYLOCOCCUS; Starches; SYNTHESIS; Tapioca; Tapioca starch; TRANSMISSION; TRANSMISSION ELECTRON MICROSCOPY; ULTRAVIOLET RADIATION; X-RAY DIFFRACTION; Zinc oxide; ZINC OXIDES
• ISSN: 1044-5803; 1873-4189
• DOI: 10.1016/j.matchar.2014.11.017

Zinc oxide nanoparticles were synthesized by gel-combustion method using novel bio-fuel tapioca starch pearls, derived from the tubers of Manihotesculenta. The product is characterized using various techniques. The X-ray diffraction pattern correspond to a hexagonal zincite structure. Fourier transform infrared spectrum showed main absorption peaks at 394 and 508cm−1 due to stretching vibration of Zn–O. Ultravoilet–visible spectrum of zinc oxide nanoparticles showed absorption maximum at 373nm whereas the maximum of the bulk zinc oxide was 377nm. The morphology of the product was studied using scanning electron microscopy and transmission electron microscopy. The scanning electron microscopic images showed that the products are agglomerated and porous in nature. The transmission electron microscopic images revealed spherical particles of 40–50nm in diameter. The photocatalytic degradation of methylene blue was examined using zinc oxide nanoparticles and found more efficient in sunlight than ultra-violet light due to reduced band gap. The antibacterial properties of zinc oxide nanoparticles were investigated against four bacterial strains Klebsiella aerogenes, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aereus, where Pseudomonas aeruginosa and Staphylococcus aereus exhibited significant antibacterial activity in agar well diffusion method when compared to positive control. •ZnO nanoparticles have been prepared from a new bio-fuel, tapioca starch by gel combustion method.•XRD pattern revealed hexagonal zincite crystal structure with crystallite size 33nm.•ZnO nanoparticles exhibited a band gap of 2.70eV.•The ZnO nanoparticles exhibited superior degradation in sunlight in comparison with UV light.•The product showed a good anti-bacterial activity against two bacterial strains.