Recent progress on dielectric polymers and composites for capacitive energy storage

Polymer dielectrics-based capacitors are indispensable to the development of increasingly complex, miniaturized and sustainable electronics and electrical systems. However, the current polymer dielectrics are limited by their relatively low discharged energy density, efficiency and poor high-temperature performance. Here, we review the recent advances in the development of high-performance polymer and composite dielectrics for capacitive energy storage applications at both ambient and elevated temperature (≥ 150 °C). We highlight the underlying rationale behind the material development by constructing the relationship between the physical properties of materials and their energy-storage capability. Challenges and future opportunities are discussed at the end of the review

Crosslinked fluoropolymers exhibiting superior high-temperature energy density and charge-discharge efficiency

Superior high-temperature discharged energy densities in comparison to those of the current dielectric polymers have been demonstrated in the crosslinked fluoropolymers

Fine-Tuning Stomatal Movement Through Small Signaling Peptides

As sessile organisms, plants are continuously exposed to a wide range of environmental stress. In addition to their crucial roles in plant growth and development, small signaling peptides are also implicated in sensing environmental stimuli. Notably, recent studies in plants have revealed that small signaling peptides are actively involved in controlling stomatal aperture to defend against biotic and abiotic stress. This review illustrates our growing knowledge of small signaling peptides in the modulation of stomatal aperture and highlights future challenges to decipher peptide signaling pathways in guard cells

Scalable Polymer Nanocomposites with Record High‐Temperature Capacitive Performance Enabled by Rationally Designed Nanostructured Inorganic Fillers

Next-generation microelectronics and electrical power systems call for high-energy-density dielectric polymeric materials that can operate efficiently under elevated temperatures. However, the currently available polymer dielectrics are limited to relatively low working temperatures. Here, the solution-processable polymer nanocomposites consisting of readily prepared Al2 O3 fillers with systematically varied morphologies including nanoparticles, nanowires, and nanoplates are reported. The field-dependent electrical conduction of the polymer nanocomposites at elevated temperatures is investigated. A strong dependence of the conduction behavior and breakdown strength of the polymer composites on the filler morphology is revealed experimentally and is further rationalized via computations. The polymer composites containing Al2 O3 nanoplates display a record capacitive performance, e.g., a discharged energy density of 3.31 J cm-3 and a charge-discharge efficiency of >90% measured at 450 MV m-1 and 150 °C, significantly outperforming the state-of-the-art dielectric polymers and nanocomposites that are typically prepared via tedious, low-yield approaches

Scalable Polymer Nanocomposites with Record High-Temperature Capacitive Performance Enabled by Rationally Designed Nanostructured Inorganic Fillers.

Next-generation microelectronics and electrical power systems call for high-energy-density dielectric polymeric materials that can operate efficiently under elevated temperatures. However, the currently available polymer dielectrics are limited to relatively low working temperatures. Here, the solution-processable polymer nanocomposites consisting of readily prepared Al2 O3 fillers with systematically varied morphologies including nanoparticles, nanowires, and nanoplates are reported. The field-dependent electrical conduction of the polymer nanocomposites at elevated temperatures is investigated. A strong dependence of the conduction behavior and breakdown strength of the polymer composites on the filler morphology is revealed experimentally and is further rationalized via computations. The polymer composites containing Al2 O3 nanoplates display a record capacitive performance, e.g., a discharged energy density of 3.31 J cm-3 and a charge-discharge efficiency of >90% measured at 450 MV m-1 and 150 °C, significantly outperforming the state-of-the-art dielectric polymers and nanocomposites that are typically prepared via tedious, low-yield approaches

Tuning Nanofillers in In Situ Prepared Polyimide Nanocomposites for High‐Temperature Capacitive Energy Storage

Modern electronics and electrical systems demand efficient operation of dielectric polymer-based capacitors at high electric fields and elevated temperatures. Here, polyimide (PI) dielectric composites prepared from in situ polymerization in the presence of inorganic nanofillers are reported. The systematic manipulation of the dielectric constant and bandgap of the inorganic fillers, including Al2O3, HfO2, TiO2, and boron nitride nanosheets, reveals the dominant role of the bandgap of the fillers in determining and improving the high-temperature capacitive performance of the polymer composites, which is very different from the design principle of the dielectric polymer composites operating at ambient temperature. The Al2O3- and HfO2-based PI composites with concomitantly large bandgap and moderate dielectric constants exhibit substantial improvement in the breakdown strength, discharged energy density, and charge–discharge efficiency when compared to the state-of-the-art dielectric polymers. The work provides a design paradigm for high-performance dielectric polymer nanocomposites for electrical energy storage at elevated temperatures

Scalable Polymer Nanocomposites with Record High-Temperature Capacitive Performance Enabled by Rationally Designed Nanostructured Inorganic Fillers.

Next-generation microelectronics and electrical power systems call for high-energy-density dielectric polymeric materials that can operate efficiently under elevated temperatures. However, the currently available polymer dielectrics are limited to relatively low working temperatures. Here, the solution-processable polymer nanocomposites consisting of readily prepared Al2 O3 fillers with systematically varied morphologies including nanoparticles, nanowires, and nanoplates are reported. The field-dependent electrical conduction of the polymer nanocomposites at elevated temperatures is investigated. A strong dependence of the conduction behavior and breakdown strength of the polymer composites on the filler morphology is revealed experimentally and is further rationalized via computations. The polymer composites containing Al2 O3 nanoplates display a record capacitive performance, e.g., a discharged energy density of 3.31 J cm-3 and a charge-discharge efficiency of >90% measured at 450 MV m-1 and 150 °C, significantly outperforming the state-of-the-art dielectric polymers and nanocomposites that are typically prepared via tedious, low-yield approaches

Tuning Nanofillers in In Situ Prepared Polyimide Nanocomposites for High-Temperature Capacitive Energy Storage

Modern electronics and electrical systems demand efficient operation of dielectric polymer-based capacitors at high electric fields and elevated temperatures. Here, polyimide (PI) dielectric composites prepared from in situ polymerization in the presence of inorganic nanofillers are reported. The systematic manipulation of the dielectric constant and bandgap of the inorganic fillers, including Al2O3, HfO2, TiO2, and boron nitride nanosheets, reveals the dominant role of the bandgap of the fillers in determining and improving the high-temperature capacitive performance of the polymer composites, which is very different from the design principle of the dielectric polymer composites operating at ambient temperature. The Al2O3- and HfO2-based PI composites with concomitantly large bandgap and moderate dielectric constants exhibit substantial improvement in the breakdown strength, discharged energy density, and charge–discharge efficiency when compared to the state-of-the-art dielectric polymers. The work provides a design paradigm for high-performance dielectric polymer nanocomposites for electrical energy storage at elevated temperatures