Joint-Free Single-Piece Flexible Thermoelectric Devices with Ultrahigh Resolution p–n Patterns toward Energy Harvesting and Solid-State Cooling

Abstract

Joints widely exist in traditional organic electronic devices that are composed of p−n modules, including organic thermoelectric (TE) devices. They often harm the performance of the devices by increasing their electrical resistance and thermal resistance. Recently, a few joint-free approaches have been reported to fabricate TE devices with a single carbon nanotube (CNT) composite film. However, the resolution of p−n patterns is low, e.g., >100 μm, with a conventional printing/dropcasting method. Herein, a plasma treatment method was reported to fabricate joint-free TE devices with a single-piece flexible CNT composite film whose performance was higher than that of traditional devices in energy harvesting and solid-state cooling. In addition, this method provided p−n patterns with a high resolution of ∼1−2 μm which is promising for making future high integration level TE devices. This method can be extended to fabricate a broad range of high integration level organic electronic devices composed of p−n modules.

Anisotropic Electrical Conductivity and Isotropic Seebeck Coefficient Feature Induced High Thermoelectric Power Factor >1800 µW m−1 K−2 in MWCNT Films

“…The obtained materials were promising for active cooling (Peltier effect) as suggested in the literature, where high power factor and high thermal conductivity were required. [ 32,42 ]…”

“…In the meanwhile, these materials are especially promising for active cooling (Peltier effect) as suggested in the literature, where high thermal conductivity and high power factor were required. [32,42] The large scalable ability and low cost of these materials are also advantageous, which makes them promising in potential practical applications. This method may be extended to other 1D-material based TE composites to boost the development of high PF flexible materials.…”

“…In addition, these materials may also be promising in developing flexible TE devices for active cooling (Peltier effect) as suggested in the literature, where high thermal conductivity and high power factor were required. [32,42] This method could be potentially extended to other 1D materials based on organic-inorganic composites to boost the development of high PF flexible TE films.…”

“…The obtained materials were promising for active cooling (Peltier effect) as suggested in the literature, where high power factor and high thermal conductivity were required. [32,42] The stability test was performed for both MWCNT w3-TCNQ0.8-P1.5 and MWCNT w3-PEI7.0-P1.5 . Both of them exhibited good stability as shown in Figure S8, Supporting Information.…”

Acid enhanced zipping effect to densify MWCNT packing for multifunctional MWCNT films with ultra-high electrical conductivity

“…al. in the literature, where high power factor and high thermal conductivity were required 43 , 44 . values were also measured for the MWCNT films, which were in the order of (CSA-MWCNT) > (HCl-MWCNT) > (annealed-MWCNT) > (pristine-MWCNT) (Fig.…”