Analyzing the Bolometric Performance of Vanadium Oxide Thin Films Modified by Carbon Nanotube Dispersions

Abstract

The influence of carbon nanotube (CNT) dispersions on the electrical properties and noise signal amplitude of VOx films is investigated. For a critical range of the CNT dispersion density on VOx films, the intrinsic properties of the VOx films are modified by the CNTs. The CNT concentrations reported in this work are about 0.3 μg/cm2 and 1.6 μg/cm2, allowing for low density and high density dispersions on the VOx film surface to be investigated. These values are higher than the percolation threshold of about 0.12 μg/cm2 for these films. The composite film exhibits a significant reduction in the temperature coefficient of resistance (TCR) (from ≈3.8% K−1 to ≈0.3% K−1) for high density dispersions. In contrast, while VOx–CNT composites with low density single wall CNT dispersions exhibit no significant change in TCR values, an approximate two orders of magnitude reduction in the low frequency 1/f noise is measured. The noise signal amplitude measured at 0.1 V and at 1.0 Hz reduces from 6 × 10−5V/(Hz) for VOx films to 5 × 10−7V/(Hz) for the low density SWCNT dispersion on VOx film and to 3 × 10−6V/(Hz) for the low density MWCNT dispersion on VOx film. The CNT concentration is the critical factor for yielding the observed changes in conductivity and low frequency noise. The results presented in this work provide a better understanding of VOx-based composites, thereby enabling the development of new, versatile and functional materials for device applications.

Fabrication and characterization of suspended La0.7Sr0.3MnO3 nanofibers for high-sensitive and fast-responsive infrared bolometer

“…In previous studies, numerous methods have been suggested to develop an affordable uncooled microbolometer, employing diverse materials such as Carbon Nanotubes (CNTs) [16][17][18][19][20][21][22][23][24], VO 2 nanowires [25], Germanium nanowires [26], Graphene [27], and spray-coated films consisting of Vanadium Oxide with CNTs [28], among others. While there is a limited body of literature discussing perovskite-based manganite fibers covering their various aspects [29][30][31][32][33][34], there is a significant gap in the literature when it comes to detailing the fabrication of suspended [16,17,28] manganite nanofibers on interdigitated electrodes (IDEs) for infrared sensing applications.…”