title: Ultrasensitive Gold Nanostar-Polyaniline Composite for Ammonia Gas Sensing.
abstract: Gold in the form of bulk metal mostly does not react with gases or liquids at room temperature. On the other hand, nanoparticles of gold are very reactive and useful as catalysts. The reactivity of nanoparticles depends on the size and the morphology of the nanoparticles. Gold nanostars containing copper have rough surfaces and large numbers of active sites due to tips, sides, corners, and large surface area-to-volume ratios due to their branched morphology. Here the sensitivity of the gold nanostar-polyaniline composite (average size of nanostars ∼170 nm) toward ammonia gas has been investigated. For 100 ppm ammonia, the sensitivity of the composite increased to 52% from a mere 7% value for pure polyaniline. The gold nanostar-polyaniline composite even showed a response time as short as 15 s at room temperature. The gold nanostars act as a catalyst in the nanocomposite. The stability and sensitivity at different concentrations and the selectivity for ammonia gas were also investigated.
authors.affiliation: Indian Institute of Science Education and Research , Dr. Homi Bhabha Road, Pashan, Pune 411008, India.
authors.forename: Vished
authors.initials: V
authors.lastname: Kumar
authors.affiliation: Thin Film Materials Laboratory, Department of Physics, Shivaji University , Kolhapur 416004, India.
authors.forename: Vithoba
authors.initials: V
authors.lastname: Patil
authors.affiliation: Indian Institute of Science Education and Research , Dr. Homi Bhabha Road, Pashan, Pune 411008, India.
authors.forename: Amey
authors.initials: A
authors.lastname: Apte
authors.affiliation: Thin Film Materials Laboratory, Department of Physics, Shivaji University , Kolhapur 416004, India.
authors.forename: Namdev
authors.initials: N
authors.lastname: Harale
authors.affiliation: Thin Film Materials Laboratory, Department of Physics, Shivaji University , Kolhapur 416004, India.
authors.forename: Pramod
authors.initials: P
authors.lastname: Patil
authors.affiliation: Indian Institute of Science Education and Research , Dr. Homi Bhabha Road, Pashan, Pune 411008, India.
authors.forename: Sulabha
authors.initials: S
authors.lastname: Kulkarni