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Thermoelectric power generators have attracted increasing interest in recent years owing to their great potential in wearable electronics power supply. It is noted that thermoelectric power generators are easy to damage in the dynamic service process, resulting in the formation of microcracks and performance degradation. Herein, we prepare a new hybrid hydrogel thermoelectric material PAAc/XG/Bi2Se0.3Te2.7 by an in situ polymerization method, which shows a high stretchable and self‐healable performance, as well as a good thermoelectric performance. For the sample with Bi2Se0.3Te2.7 content of 1.5 wt% (i.e., PAAc/XG/Bi2Se0.3Te2.7 (1.5 wt%)), which has a room temperature Seebeck coefficient of −0.45 mV K−1, and exhibits an open‐circuit voltage of −17.91 mV and output power of 38.1 nW at a temperature difference of 40 K. After being completely cut off, the hybrid thermoelectric hydrogel automatically recovers its electrical characteristics within a response time of 2.0 s, and the healed hydrogel remains more than 99% of its initial power output. Such stretchable and self‐healable hybrid hydrogel thermoelectric materials show promising potential for application in dynamic service conditions, such as wearable electronics. [ABSTRACT FROM AUTHOR]

The irresistible trend towards the higher power density of the next generation integrated circuits (ICs) has brought inevitable issues of electromagnetic interference and thermal runaway, which are hard to solve merely by polymer-based packaging materials. As demonstrated in this work, an epoxy-based composite with efficient electromagnetic wave (EMW) absorption and flame-retardant performances was fabricated to meet the needs. The combination of hollow carbon spheres (HCS) and multi-scale nickel ferrites (i.e., NF@HCS/NF) was proved to be a successful approach toward the strong absorption of incident EMW, with the lowest reflection loss (designated as RLmin) value of −59.5 dB at a matching thickness of 2.0 mm and an effective absorption bandwidth (EAB) of 2.9 GHz. Moreover, the NF@HCS/NF/EP composite exhibits high thermal stability and flame retardancy owing to the physical barrier effect of naturally non-combustible NF, with an 8% higher thermal decomposition temperature (T10% using here) and a 37.5% reduced total heat release (THR) value compared to pure EP. Besides, the NF@HCS/NF/EP composite possesses a volumetric resistivity of ∼3 × 1011 Ω cm and a low viscosity of ∼10 000 MPa s, indicating properties of high electrical insulation and fluidity. Such an NF@HCS/NF/EP composite with high EMW absorption, flame retardancy, electrical insulation, and fluidity suggests its potential in the advanced electronic packaging field. [ABSTRACT FROM AUTHOR]

The long‐term and stable operation of integrated circuits and microelectronics requires packaging epoxy resin (EP) exhibit high thermal conductivity for efficient heat dissipation, and excellent flame retardancy in case of thermal runaway. We achieved such EP composite via filling poly‐dopamine (PDA) modified nanoscale Al2O3 spheres and microscale h‐BN sheets. The PDA modification increases the compatibility between fillers and EP and largely reduces the viscosity, improving the dispersion of fillers in EP thus the thermal conductivity of EP composites. In addition, NH3, H2O, and N2 generated during the combustion of phenolic hydroxyls and aminos in PDA combined with the physical barrier effect of Al2O3 and h‐BN can improve the flame retardancy of EP composites. As a consequence, the EP composite filled with PDA modified Al2O3 (26.67 wt%) and h‐BN (13.33 wt%) (i.e., PDA‐BNAO/EP) shows a thermal conductivity of 1.192 W/mK (654.9% of EP), a peak heat release rate of 194.9 W/g (33.8% of EP), and total heat release of 15.2 kJ/g (54.5% of EP), respectively. What's more, the viscosity of PDA‐BNAO/EP is 20,443 mPa s, which is only 20% of BNAO/EP (whose viscosity is 102,281 mPa s). More importantly, the PDA‐BNAO/EP has good dynamic mechanical properties with the storage modulus of 14.69 Gpa, glass transition temperature of 91.9°C and good electrical insulation, which is desired for packaging of microelectronics. PDA‐BNAO/EP composite should be a promising candidate for widespread packaging materials of microelectronics. [ABSTRACT FROM AUTHOR]