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Thermal conductive polymer composite prepared by 3D printing technology, which has a highly vertically oriented carbon fiber structure.

Newly one-dimensional hydroxyapatite nanowires are synthesized and applied in P(VDF–HFP) nanocomposites for energy storage application. Excellent Ud of ∼27.6 J cm−3 accompanied with high η of ∼72.9% at Eb of 650 MV m−1 are achieved.

Considering the significant threat of heat to electronic equipment and the heat dissipation problems existing in powerful systems, thermal management materials are in high demand. In conjunction with the increasing desire of dissipating heat and stabilizing temperature, high thermal conductivity and phase change latent heat are attracting more attention when designing thermal management material. This work proposes a strategy to combine phase change matrix and thermally conductive filler using freeze casting. The highest thermal conductivity reaches 23.1 W m-1 K-1 accompanied by 62 J g-1 phase change latent heat. Meanwhile, replacing ice with organic phase change material in freeze casting can result in an aligned structure. This discovery will pave a novel way for introducing thermal latent heat without abandoning the aligned structure.

Sandwich-structured polymer nanocomposites exhibit remarkable capacitive energy storage performance, including high energy density, great charge–discharge efficiency and excellent dielectric stability at elevated temperatures.

Simultaneous achievement of high thermal transportation performance and superior mechanical properties in a same thermal management composite film.

Correction for ‘Ultrahigh thermal conductive polymer composites by the 3D printing induced vertical alignment of carbon fiber’ by Zhenbang Zhang et al., J. Mater. Chem. A, 2023, https://doi.org/10.1039/D3TA01676E.

High-performance electrostatic capacitors are in urgent demand owing to the rapid development of higher power electronic applications. However, developing polymer-based composite films with both a high breakdown strength (Eb) and dielectric constant (er) is still a huge challenge. Here, hierarchically structured SrTiO3@SrTiO3 nanofibers (ST@ST NFs), in which crystalline SrTiO3 nanoparticles are embedded into the amorphous SrTiO3 nanofibers, are incorporated into the poly(vinylidene fluoride-co-hexafluoropropene) (P(VDF-HFP)) matrix to form a multiscale internal/external interface to break the paradox of a high er with decreased Eb, and that in turn gives rise to a remarkably improved energy storage capability. The percolation of the SrTiO3–SrTiO3 interfaces could promote interfacial polarization, resulting in a substantially increased er of the polymer nanocomposites at a rather low concentration of nanofillers. More importantly, the improved Eb of 630 MV m−1 is also achieved through the multiscale internal/external interface. These very favorable values give rise to an ultrahigh discharged energy density (Ud) of ∼25.26 J cm−3, which is 283% of the value of the pure P(VDF-HFP) film. A record enhancement ratio of Ud is achieved in this work among the previously reported results to the best of our knowledge. This approach provides a new dimension of interface engineering to adjust and improve the energy storage properties of polymer nanocomposites.

Vacuum filtration is a highly effective and easy scale-up approach and has been widely used to fabricate graphene monoliths, such as graphene paper and graphene frameworks for various applications. In general, the microstructure of filtrated monoliths exhibits layer-by-layer stacking of graphene sheets due to the directional flow-induced assembly process. In this work, we found that the horizontally oriented structure of filtrated graphene frameworks can be modulated to an approximately isotropic arrangement by lowering the lateral size of graphene sheets. This size-dependent microstructure transition from anisotropic to isotropic was further confirmed by measuring the in- and through-plane thermal conductivity of the graphene/epoxy composites with different arrangements of graphene frameworks as a filler. Optimally, we obtained an epoxy composite embedded with a quasi-isotropic graphene framework (QIGF) by a simple two-step process: vacuum filtration of small graphene sheets to obtain the framework followed by the infiltration of epoxy resin. Based on the interconnected graphene sheets with an approximately isotropic arrangement, QIGF provides heat channels of graphene–graphene along both the in- and through-plane directions within epoxy. With a low graphene loading of 5.5 wt%, QIGF/epoxy (QIGF/EP) presents in- and through-plane thermal conductivities of 10.0 and 5.4 W mK−1, respectively, which are equivalent to ∼55 and 29 times higher than those of neat epoxy. As compared to the current graphene/epoxy composites prepared by various methods, our QIGF/EP has the highest thermal conductivity value with this level of filler loading. Our findings provide an insight for the development of polymer composites for thermal management applications in industry.

Based on the fast growth of the device performance, there has been an increasing demand for handling the issue of thermal management in electronic equipments. Therefore, it is of great significance to improve the thermal conductivity of thermoplastics, which are commonly used in electronic components. However, the difficulty of graphene dispersion and strong interfacial phonon scattering restrict the heat dissipation performance of graphene/thermoplastic composites, especially in the case of polypropylene (PP) or polyethylene (PE). Here, we propose a single-step and versatile approach to fabricate graphene/thermoplastic composites with a remarkable thermal conductivity enhancement. The composites were prepared by coating graphene on polymer powder first, followed by hot pressing. As a result, an interconnected graphene framework can be developed in the thermoplastic matrix, leading to significant heat transfer enhancement of the composites. At a 10 wt% graphene content, the thermal conductivity reaches 1.84, 1.53, 1.43, and 1.47 W m−1 K−1 for PE, PP, PVA (poly(vinyl alcohol)), and PVDF (poly(vinylidene fluoride)) composites, respectively. Our finding provides a path to develop a variety of highly thermally conductive thermoplastic composites for use in heat dissipation and other thermal applications.

We report a facile and general approach for the synthesis of boron nitride nanosheet (BNNS)–metal nanoparticle (NP) composites at room temperature without adding any reducing agent. BNNS was exfoliated in hydroxide aqueous media using tip-sonication. The resulting BNNS possessed abundant hydroxyl groups which reduced the gold salt and enabled the in situ growth of uniform Au NPs on BNNS (average diameter of 17 nm). The as-synthesised BNNS–Au NP composite exhibited outstanding catalytic and electrocatalytic activities which were confirmed by its excellent performance in the chemical degradation of Rhodamine B and electrocatalytic oxidation of hydrazine, respectively. This method was also demonstrated to be a general approach for the preparation of other BNNS–metal NP composites by the in situ growth of Ag, Pd and Pt NPs on BNNS.

A rigid three-dimensional structure composed of silicon carbide (SiC) nanowire@graphene sheets (3DSG) was prepared using a high frequency heating process. The polyamide acid was then infused into the three-dimensional structure and imidized at 350 °C. The thermal conductivity of polyimide (PI)/3DSG composites with 11 wt% filler addition can be up to 2.63 W m−1 K−1, approximately a 10-fold enhancement when compared with the results obtained using neat PI. Furthermore, the 3DSG shows a better synergistic effect in thermal conductivity improvement, relative to a simple mixture of SiC nanowires and graphene sheets (GSs) fillers with the same additive content. The reinforced thermal properties can be attributed to the formation of efficient heat conduction pathways among GSs.