Superior High‐Temperature Energy Density in Molecular Semiconductor/Polymer All‐Organic Composites

Abstract

High‐temperature dielectric polymers are in constant demand for the multitude of high‐power electronic devices employed in hybrid vehicles, grid‐connected photovoltaic and wind power generation, to name a few. There is still a lack, however, of dielectric polymers that can work at high temperature (> 150 °C). Herein, a series of all‐organic dielectric polymer composites have been fabricated by blending the n‐type molecular semiconductor 1,4,5,8‐naphthalenetetracarboxylic dianhydride (NTCDA) with polyetherimide (PEI). Electron traps are created by the introduction of trace amounts of n‐type small molecule semiconductor NTCDA into PEI, which effectively reduces the leakage current and improves the breakdown strength and energy storage properties of the composite at high temperature. Especially, excellent energy storage performance is achieved in 0.5 vol.% NTCDA/PEI at the high temperatures of 150 and 200 °C, e.g., ultrahigh discharge energy density of 5.1 J cm−3 at 150 °C and 3.2 J cm−3 at 200 °C with high discharge efficiency of 85–90%, which is superior to its state‐of‐the‐art counterparts. This study provides a facile and effective strategy for the design of high‐temperature dielectric polymers for advanced electronic and electrical systems.

(Bi1/6Na1/6Ba1/6Sr1/6Ca1/6Pb1/6)TiO3-based high-entropy dielectric ceramics with ultrahigh recoverable energy density and high energy storage efficiency

“…Temperature stability of energy storage properties is a pivotal index to evaluate the working status of capacitors under variable temperature or high-temperature environments. 61 Fig. 9(a) illustrates the unipolar P – E loops of x = 0.12 measured under 350 kV cm −1 at the temperature range of 25 °C to 180 °C.…”

Enhancing energy storage performance in Na0.5Bi0.5TiO3-based lead-free relaxor ferroelectric ceramics along a stepwise optimization route

“…Ceramic dielectric capacitors are capably competitive in electronic systems because of their high-power density, strong voltage resistance, and prominent reliability. [1][2][3] Their poor energy storage density, however, remains an impediment to meeting the demands for advanced electronic system integration and downsizing. 4,5 To compensate for this shortcoming, reduce energy loss, and adapt to diverse temperature conditions, ceramic capacitors with high energy storage density (W rec ), energy efficiency (h), and great thermal adaptation are required.…”

“…6 In this regard, relaxor ferroelectrics (RFEs) have a high DP value and a moderate E b , giving them advantages and superiorities over ferroelectrics (FEs), antiferroelectrics (AFEs), and linear dielectrics (LDs), all of which have advantages and disadvantages in energy storage applications. 3 Perovskite (Na 0.5 Bi 0.5 )TiO 3 (NBT)-based RFE ceramics have been extensively studied in the past decade. 4,5,[7][8][9][10][11][12][13][14][15] Because the valence electron conguration of Bi 3+ (6s 2 6p 0 ) is comparable to that of Pb 2+ and orbital hybridization between Bi 6p and O 2p normally generates a higher P m , prototypical NBT has a high P m greater than 40 mC cm −2 .…”

“…6 In this regard, relaxor ferroelectrics (RFEs) have a high Δ P value and a moderate E b , giving them advantages and superiorities over ferroelectrics (FEs), antiferroelectrics (AFEs), and linear dielectrics (LDs), all of which have advantages and disadvantages in energy storage applications. 3…”

Molecular Trap Engineering Enables Superior High‐Temperature Capacitive Energy Storage Performance in All‐Organic Composite at 200 °C

“…[ 21 ] More recently, a discharged energy density of 2.7 J cm −3 with 90% efficiency at 200 °C has been obtained in PEI doped with n‐type organic semiconductor 1,4,5,8‐naphthalenetetracarboxylic dianhydride (NTCDA). [ 22 ] Alternatively, the rational molecular design of polymers has been used to intrinsically enhance the capacitive energy storage performance. [ 23,24 ] For example, improved capacitive performance has been achieved at 150 °C in polyoxafluoronorbornene and poly(styrene‐ co ‐maleic anhydride) networks by controlling the bandgap and the energy levels of trap states, respectively.…”