Trihigh tricontinuous graphene cathode enables a 1.1 s charge, 250,000 cycle life, wide temperature range Al-ion battery.

A conceptually new defect-free principle is proposed for designing graphene cathode of aluminum-ion battery: the fewer the defects, the better the performances. Developed through scalable approach, defect-free graphene aerogel cathode affords high capacity of 100 mAh g under an ultrahigh rate of 500 C, exceeding defective graphene and previous reports. This defect-free principle can guide us to fabricate better graphene-based electrodes.

Graphene aerogel microlattices (GAMs) hold great prospects for many multifunctional applications due to their low density, high porosity, designed lattice structures, good elasticity, and tunable electrical conductivity. Previous 3D printing approaches to fabricate GAMs require either high content of additives or complex processes, limiting their wide applications. Here, a facile ion‐induced gelation method is demonstrated to directly print GAMs from graphene oxide (GO) based ink. With trace addition of Ca2+ ions as gelators, aqueous GO sol converts to printable gel ink. Self‐standing 3D structures with programmable microlattices are directly printed just in air at room temperature. The rich hierarchical pores and high electrical conductivity of GAMs bring admirable capacitive performance for supercapacitors. The gravimetric capacitance (Cs) of GAMs is 213 F g−1 at 0.5 A g−1 and 183 F g−1 at 100 A g−1, and retains over 90% after 50 000 cycles. The facile, direct 3D printing of neat graphene oxide can promote wide applications of GAMs from energy storage to tissue engineering scaffolds.

Polymer-based thermal interface materials (TIMs) with excellent thermal conductivity and electrical resistivity are in high demand in the electronics industry. In the past decade, thermally conductive fillers, such as boron nitride nanosheets (BNNS), were usually incorporated into the polymer-based TIMs to improve their thermal conductivity for efficient heat management. However, the thermal performance of those composites means that they are still far from practical applications, mainly because of poor control over the 3D conductive network. In the present work, a high thermally conductive BNNS/ epoxy composite is fabricated by building a nacre-mimetic 3D conductive network within an epoxy resin matrix, realized by a unique bidirectional freezing technique. The as-prepared composite exhibits a high thermal conductivity (6.07 W m −1 K −1 ) at 15 vol% BNNS loading, outstanding electrical resistivity, and thermal stability, making it attractive to electronic packaging applications. In addition, this research provides a promising strategy to achieve high thermal conductive polymer-based TIMs by building efficient 3D conductive networks.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adfm.201900412. graphene [12] (1-16 W m −1 K −1 ), and carbon nanotubes [13] (CNTs, 0.5-5 W m −1 K −1 ) are usually included in the polymer matrix. Among all those fillers, boron nitride (BN) is particularly outstanding for its high thermal conductivity, excellent electrical insulation, and low cost. [14] During the last decade, although many efforts have been made to develop BN-based polymer composite, [15][16][17][18] its real application as TIM is greatly hindered for its moderate thermal conductivity. This could be mainly attributed to the insufficient manipulation of the 3D conductive network. For the same reason, currently reported composites are usually thin films although there is an urgent need for bulk BN-based composite with high thermal conductivity.Here, a BN/epoxy composite with a nacre-mimetic 3D conductive network was constructed by a bidirectional freezing technique. [19][20][21] The boron nitride nanosheets (BNNS) were assembled into an aerogel with long-range aligned lamellar layers, followed by infiltration of epoxy resin. The highly organized 3D conductive network provides prolonged phonon pathways, yielding a much higher thermal conductivity (6.07 W m −1 K −1 ) at a relatively low BN loading (15 vol%) comparing to the similar composites in the literature. Together with its excellent electrical resistivity (2 × 10 12 Ω cm) and thermal stability (glass transition temperature: 120 °C), our composite may find wide applications including TIM for the advanced electronic packaging technology. Keywords3D conductive network, bidirectional freezing, boron nitride, long-range lamellar structure, thermal interface material

Continuous MXene/graphene fibers are fabricatedviawet-spinning assembly strategy, from which fiber-constructed supercapacitors are obtained that exhibit both high capacitance and flexibility.