Anomalous temperature coefficient of resistance in graphene nanowalls/polymer films and applications in infrared photodetectors

Abstract

Graphene nanowalls (GNWs) exhibit outstanding optoelectronic properties due to their peculiar structure, which makes them a great potential in infrared (IR) detection. Herein, a novel IR detector that is composed of polydimethylsiloxane (PDMS) and designed based on GNWs is demonstrated. Such detector possesses an anomalous temperature coefficient of resistance of 180% K −1 and a relatively high change rate of current (up to 16%) under IR radiation from the human body. It primarily attributes to the ultra-high IR absorption of the GNWs and large coefficient of thermal expansion of PDMS. In addition, the GNW/PDMS device possesses excellent detection performance in the IR region with a responsivity of ~1.15 mA W , which is one or two orders of magnitude larger than that of the traditional carbon-based IR detectors. The significant performance indicates that the GNW/PDMS-based devices reveal a novel design concept and promising applications for the future new-generation IR photodetectors.

Preparation and Bolometric Responses of MoS2 Nanoflowers and Multi-Walled Carbon Nanotube Composite Network

“…The strong nonlinear behavior resulted from the temperature-sensitive interconnection among graphene flakes [51]. In the literature, it was found that the temperature coefficient of resistance of graphene nanowall-polymer films changed from around 6%/K at 25 • C to 180%/K at 40 • C due the thermal strain effect [64]. Thus, the strain effect on CNTs is expected to contribute to the higher TCR of the CNT-MoS 2 composite network.…”

Recent Developments in Printing Flexible and Wearable Sensing Electronics for Healthcare Applications

“…The sensors were responsive despite being insulated with an overlying layer as protection against all these environmental variations. Graphene nano-wells show tremendous temperature coefficients of resistance (i.e., 180% K −1 ), which is an interesting development for the detection of human body temperature [ 129 ]. A biocompatible conductive green electrolyte is another attractive candidate for in vivo and in vitro body temperature measurements [ 46 ].…”

Graphene Quantum Dot-Decorated Vertically Oriented Graphene/Germanium Heterojunctions for Near-Infrared Photodetectors

“…VOG, a vertical structure formed by the overlap of longitudinally grown graphene films, not only possesses similar electrical characteristics as graphene films but also exhibits excellent light absorption from the near-infrared (NIR) to infrared (IR) region because of the edge effects and uniform index of refraction at the interface. − The unique structural/electrical properties of VOG are advantageous to the transport of photo-generated carriers and decrease recombination on the surface . Direct growth of VOG on arbitrary substrates by plasma-assisted chemical vapor deposition (PACVD) ensures the high quality of Schottky junction and improves the device performance. , Besides, GQDs as a novel class of carbon nanomaterials have undergone tremendous development in the past few years because of the unique electronic, optical, and chemical properties in conjunction with quantum confinement and edge effects. , Compared to traditional graphene derivatives, the enhanced solubility of GQDs is ideal for solution processing, thus boosting the production yields.…”

“…17−19 The unique structural/ electrical properties of VOG are advantageous to the transport of photo-generated carriers and decrease recombination on the surface. 20 Direct growth of VOG on arbitrary substrates by plasma-assisted chemical vapor deposition (PACVD) ensures the high quality of Schottky junction and improves the device performance. 18,21 Besides, GQDs as a novel class of carbon nanomaterials have undergone tremendous development in the past few years because of the unique electronic, optical, and chemical properties in conjunction with quantum confinement and edge effects.…”