The role of nitrogen-carbon dots (NC) nano-particles in enhancing thermoelectric power functions of PEDOT:PSS/Te nano-composite films

Lately, thermoelectric materials have attracted attentions because they have the ability to generate electricity from a small amount of heat. Moreover, nano-composite materials based on conducting polymers are extensively applied due to their unique thermoelectric functions besides their flexibility, harmlessness, and abundance. In this regards, new nano-composite films based on Nitrogen doped Carbon nano-dots (NC) decorated Telluride (Te) nano-rods embedding into Poly(3,4-ethylene-dioxythiophene):Poly(styrenesulphonate) (PEDOT:PSS/Te-NC@) have been engineered for the thermoelectric applications. The impact of NC nano-dots on the anisotropic thermoelectric functions of the PEDOT:PSS/Te-NC@ was briefly studied. The thermoelectric functions of PEDOT: PSS/Te-NC@ nano-composite films are significantly improved by the decoration of NC nano-dots on the Te surfaces. 3 wt% NC nano-dots allow the through plane electrical conductivity (165.3 +/- 5 S/cm) to increase by similar to 5 times when compared with PEDOT:PSS/Te (31.9 +/- 4 S/cm) due to the creation of Te-NC@ conductive paths inside the films and the increase in the carrier mobility. At 3 wt% NC, the through plane Seebeck coefficient (95.3 +/- 3 mu V/K) decreases by similar to 1.5 times lower than PEDOT:PSS/Te (146.8 +/- 2 mu V/K), as well as, the through plane power factor increases to be 154.6 +/- 3 mu V/mK(2) due to the increase in both the carrier mobility and carrier concentration. Interestingly, under control through plane thermal conductivity behavior has been observed for PEDOT: PSS/Te-NC@ nano-composite films due to the creation of a gaseous atmosphere of nitrogen which occupies the defects and voids in the nano-composite. PEDOT:PSS/Te-NC@ nano-composite films exhibit a through plane figure of merit zT similar to 0.355 at a small amount of NC (3 wt%) at room temperature, which is considered one of the largest zT values as compared to their counterparts. Besides, the in plane thermoelectric functions have been briefly studied in order to introduce a full description for these thermoelectric materials.

Automated summary

Recently, there has been a growing interest in thermoelectric materials and nano-composite materials based on conducting polymers due to their unique thermoelectric functions as well as flexibility, harmlessness, and abundance. New nano-composite films based on Nitrogen doped Carbon nano-dots decorated Telluride nano-rods have been designed, showing significant improvements in their thermoelectric properties. The introduction of Nitrogen doped Carbon nano-dots led to enhanced electrical conductivity, decreased Seebeck coefficient, and increased power factor, resulting in improved thermoelectric performance of the composite films.