NiFe2O4/Poly(1,6-heptadiyne) Nanocomposite Energy-Storage Device for Electrical and Electronic Applications

ACS Omega. 2018 Nov 12;3(11):15256-15266. doi: 10.1021/acsomega.8b02306. eCollection 2018 Nov 30.

Abstract

In present study, we have synthesized intrinsically conductive poly(1,6-heptadiynes) via cyclopolymerization technique, and further it is composited with the NiFe2O4 to fabricate pellet for electrical and electronic applications. The synthesized polymer I-V characteristics were obtained by two-probe measurement technique. The results suggest that the high current density of the synthesized polymer was in the range of 1.2 × 10-5-3.1 × 10-5 S/cm, which attributes to the potentially induced hoping charge-carrier mechanism within the conjugated poly(1,6-heptadiynes). NiFe2O4 and NiFe2O4/poly(1,6-heptadiynes) composite pellets were fabricated by utilizing hydraulic pelletizer. The sample's electrical measurements were performed via broad-band dielectric impedance spectroscopy, wherein the composite permittivity was about ε = 45 (100 Hz to 10 kHz), which attributes to the NiFe2O4 and poly(1,6-heptadiynes) phases; further, this describes the capacitance, which improved from 0.3 to 0.1 pf at 1 kHz. Also, these results suggest the reduced equivalent series resistance (72.1-1 MHz), which attributes to the incorporated intrinsically conducting poly(1,6-heptadiynes). Thus, the reduced dissipation factor (DF = 0.0032) was observed from impedance characteristics of a nanocomposite. Moreover, the improved Q-factor was observed, which was about 8.1-310 at 1 kHz. The resistance and capacitance time constant was also computed to be about 0.29 μs at 1 kHz for NiFe2O4/poly(1,6-heptadiynes) nanocomposite. Furthermore, the nanocomposite-enabled capacitor gravimetric energy density and power densities were calculated to be about 0.00575 mJ/g and 9.91 W/g, respectively. Additionally, thermal threatening, that is, heat generated within the capacitor, P loss is also estimated for the nanocomposite capacitor, which improved from 0.0006 to 8.9 × 10-6, and these results suggest improved nanocomposite thermal stability. Further, the delineated quantities were compared to the commercially available configurations of tantalum hybrid capacitors and Al and Ta electrolytic capacitors, including carbon electrochemical capacitors, which suggest that the reported nanocomposites could be a suitable candidate for electrical and electronic applications.