Band Engineered I/III/V–VI Binary Metal Selenide/MWCNT/PANI Nanocomposites for Potential Room Temperature Thermoelectric Applications

Abstract

Room temperature thermoelectric studies are reported herein of ternary hybrids fabricated by ex situ processing involving polyaniline (PANI), multiwalled carbon nanotubes (MWCNTs), and binary metal selenide nanoparticles (MSe NPs) such as CuSe, Ag 2 Se, In 2 Se 3 , and Sb 2 Se 3 synthesized by using cyclohexeno-1,2,3-selenadiazole (SDZ) as selenium precursor. The presence of phase pure MSe NPs in ternary hybrids was confirmed by XRD analysis. FTIR analysis suggested a strong π−π interaction between PANI and MWCNTs. Electrical conductivities, Seebeck coefficients, and power factors of these band engineered ternary nanocomposites were investigated at room temperature. Ag 2 Se NPs/MWCNT/PANI (ASCP) showed p-type behavior with figure of merit (zT) of 0.012 at room temperature, while other hybrids exhibited n-type behavior. All of the ternary hybrids showed high electrical conductivities, and among ntype hybrids, CuSe NPs/MWCNT/PANI showed the best thermoelectric performance. The present work opens up an efficient approach to enhance the utility of metal chalcogenides as sensitizers in thermoelectric applications. The possible mechanism for charge transport is also discussed.

Transition Metal Selenides for Electrocatalytic Hydrogen Evolution Reaction

“…Apart from application in electrocatalytic hydrogen production as excellent cathodic catalysts, TMSs are also utilized as catalysts of oxygen evolution reaction (OER), oxygen reduction reaction (ORR) . Otherwise, attributed to TMSs’ intriguing physicochemical properties, they have been applied in extensive fields, e. g., photocatalysts, electrochemical energy storage devices (ion batteries, supercapacitors), dye‐sensitized solar cells, sensitivity glucose sensors, photodetectors, thermoelectric materials …”

“…[140] Otherwise, attributed to TMSs' intriguing physicochemical properties, they have been applied in extensive fields, [141] e. g., photocatalysts, [142] electrochemical energy storage devices (ion batteries, supercapacitors), [143] dye-sensitized solar cells, [144] sensitivity glucose sensors, [145] photodetectors, [146] thermoelectric materials. [147]…”

Recent Progress of Two-Dimensional Thermoelectric Materials

“…As a potential high-performance thermoelectric material, conductive polymers exhibit unique advantages such as a low thermal conductivity, flexibility, lightweight, and efficient solution processability [9,[198][199][200][201][202]. However, more work needs to be done to further improve their thermoelectric performance to use them in flexible and wearable thermoelectric devices.…”

Recent Advances in Polyaniline-Based Thermoelectric Composites

“…Therefore, properly modulating the interfacial interactions and interface energy barrier can be an effective approach for achieving high S and σ synergistically, either in binary or ternary hybrids. [88][89][90][91] For instance, Meng et al fabricated PANI-coated multi-walled CNTs sheet with CNT network sheet that served as the template for the deposition of polymer chains, forming PANI coating layer on the surface of CNTs. 19 The conductive CNT network and energy-filtering effect at interfaces which preferentially allow the high energy carriers to pass contribute to the improved σ and S, resulting in maximum PF of 5 μW m -1 K -2 at 84 wt% CNT, higher than individual constituent.…”