High-quality textured SnSe thin films for self-powered, rapid-response photothermoelectric application

The ultralow thermal conductivity and tunable thermoelectric properties of surfactant-free SnSe nanocrystals

“…Interestingly, both p-and n-type NCs show lower thermal conductivity values than the previously reported values for SnSe single crystals or solution-processed lm/pellet samples. 8,9,22,27,31 Ultralow thermal conductivities were observed in p-type SnSe NCs (0.19 to 0.1 W m À1 K À1 ) in the temperature region of 298-438 K. These values are the lowest gures achieved for solution-processed p-type SnSe NCs. On the other hand, MAI-treated n-type SnSe NCs showed slightly higher thermal conductivities of 0.2 to 0.14 W m À1 K À1 from 298 to 438 K. Interestingly, the ultralow thermal conductivity of 0.14 W m À1 K À1 at 438 K is a new record for n-type SnSe NCs.…”

“…9,12,15,[17][18][19][20] Other innovative strategies like phase texturing and nanostructuring have also been studied. 11,13,14,16,[21][22][23][24] However, we note that nanostructured SnSe has mostly been studied in the form of pellets, where aggressive processing and sintering can lead to a decrease in the nanocrystalline aspect of domains. The phase texturing of SnSe with another phase such as SnSe 2 presents challenges relating to controlling the growth of the two phases, and this is usually achieved via the time-dependent annealing of the lm.…”

“…14,25,26 On the other hand, sub-10 nm SnSe nanocrystals (NCs) could lead to the strong scattering of phonons at the grain boundaries and, hence, lower thermal conductivity. 10,14,22,27,28 Recently, ultralow thermal conductivity of 0.08 W m À1 K À1 was reported by Burton et al using nanostructured SnSe lm, with the lm obtained through an advanced thermal evaporation technique. 10 However, nanostructured SnSe NCs show high thermal conductivities when processed in the form of pellets, probably due to loss of the nanocrystalline aspect of the grains.…”

Series Photothermoelectric Coupling Between Two Composite Materials for a Freely Attachable Broadband Imaging Sheet

“…With the emergence of the Internet of Things (IoT) society, flexible and freely attachable photothermoelectric (PTE) sensing and visualization applications are increasingly becoming a major topic in the material and device investigation fields. To make flexible PTE sensing/imaging devices practically available, namely, comprehensively assuring the safety/quality of the social components via multiview broadband uncooled photomonitoring, diverse materials have been studied, including graphene, [ 1 ] carbon nanotubes (CNTs), [ 2,3 ] MoS2, [ 4 ] SnSe, [ 5 ] NbS3, [ 6 ] and PEDOT:PSS. [ 7 ] Among these candidates, randomly stacked CNT films demonstrate remarkable properties.…”

Robot-assisted, source-camera-coupled multi-view broadband imagers for ubiquitous sensing platform

“…Among the various potential photo-detection mechanisms, the PTE technique is chosen because it facilitates the proposed scheme via advantageous broadband operation compared to electronic-type detectors, and the advantageous uncooled characteristic of the photo-imager compared to photon-type devices 30 . Several studies have reported on different materials for functional photo-imagers, including graphene 31 , CNT 32 , MoS 2 33 , SnSe 34 , NbS 3 35 and PEDOT:PSS 36 . Among them, randomly stacked single-walled CNT (SWCNT) films are employed as the device channels in this study; this is because, when compared to the aforementioned materials, the CNT films collectively demonstrate high mechanical strength 37 , flexibility 38 and advantageous excellent uncooled broadband photo-absorption 39 .…”