Doped Polyaniline/Graphene Composites for Photothermoelectric Detectors

Abstract

The development of photothermoelectric (PTE) detectors has drawn much attention and is a hot research topic because of their superiority of converting broadband terahertz to mid-infrared radiation energy without any bias support in ambient conditions. However, earlier work in PTE detectors is complicated by a sophisticated fabrication process, uncontrollable formation, poor flexibility, and intractable material instability. Herein, we apply doped polyaniline (PANI)/graphene composites on poly(ethylene terephthalate) substrates to propose a new type of PTE detectors. The facile fabrication process, involving tip sonification and magnetic stirring, enhances the dispersion of homogeneously aqueous graphene. Besides the uniformity of the composite, the bias-free photodetector exhibits its highly sensitive responsivity by tuning the graphene concentration, achieving a peak detectivity of 6.8 × 10 7 cm Hz 1/2 W −1 and responsivity of 2.5 V W −1 . In addition, various bending radii (−1.5 to 1.5 cm) and more than 300 multiple bending cycles demonstrate remarkable flexibility of the doped-PANI/graphene composite. We further simulate human interactions by setting fingers 3−5 mm away from detectors and moving fingertips along the perpendicular direction toward the detector in multiple attempts to exhibit a rapid, high-performance photovoltage response of 10 μV. Overall, the striking doped-PANI/graphene composite PTE detectors manifest satisfactory broadband detectivity and provide insights into abundant applications in nondestructive health monitors, future optical detectors, and wearable Internet of Things (IoT) devices.

Recent Advances in the Nanomaterials, Design, Fabrication Approaches of Thermoelectric Nanogenerators for Various Applications

“…Moreover, the insolubility of PANI makes it more stable in humid environments than PEDOT:PSS. [39] To increase the low Seebeck coefficient and increase electrical conductivity, many studies investigate combining PANI with carbon nanomaterials like CNTs, [184] graphene [185] and graphene oxide. [186] Wu et al [183] fabricated an PANI/SWCNTs thin film that exhibited a high electrical conductivity of 3000 S cm −1 and a Seebeck coefficient of 40 µV K −1 (4-times-higher than pristine PANI).…”

“…Moreover, the insolubility of PANI makes it more stable in humid environments than PEDOT:PSS. [ 39 ] To increase the low Seebeck coefficient and increase electrical conductivity, many studies investigate combining PANI with carbon nanomaterials like CNTs, [ 184 ] graphene [ 185 ] and graphene oxide. [ 186 ] Wu et al.…”

System design of large-area vertical photothermoelectric detectors based on carbon nanotube forests with MXene electrodes

“…10,11 The PTE detectors based on multi-layer graphenes also show similar issues. 12 Additionally, the unstable ambient properties of black phosphorus and the toxic Pb element of perovskites also limit extended research. 13 Polymer-based composites face the challenges of low infrared absorption and temperature endurance.…”

Flexible Multi-Element Photothermoelectric Detectors Based on Spray-Coated Graphene/Polyethylenimine Composites for Nondestructive Testing

“…Among these photon energy conversions, PTE, transferring photon energy within the photothermal and thermoelectric process, 7 is outstanding due to broadband detectivity from terahertz to visible range, room-temperature working conditions without any bias support, and feasible array integration. 8 Such advantages provide potential applications in industry monitoring, 9 biomedical delivery, 10 food safety, 11 wearable Internet of Things (IoTs), 12 and energy harvest. 13 Currently, a wide range of PTE nanomaterials have been investigated, such as graphene, 14 MXene, 15 black phosphorus, 16 transition metal dichalcogenides, 17,18 reduced graphene oxide, 19 carbon nanotubes, 20 gallium compounds, 21 indium arsenide, 22 and three-dimensional microporous graphene.…”

“…Therefore, the recent understanding of absorbing IR wavelength mechanisms, including the bolometric effect, photovoltaic effect, and photothermoelectric (PTE) effect, attracts considerable and increasing attention. Among these photon energy conversions, PTE, transferring photon energy within the photothermal and thermoelectric process, is outstanding due to broadband detectivity from terahertz to visible range, room-temperature working conditions without any bias support, and feasible array integration . Such advantages provide potential applications in industry monitoring, biomedical delivery, food safety, wearable Internet of Things (IoTs), and energy harvest …”