Efficient removal of heat via thermal interface materials has become one of the most critical challenges in the development of modern microelectronic devices. However, traditional polymer composites present limited thermal conductivity even when highly loaded with highly thermally conductive fillers due to the lack of efficient heat transfer channels. In this work, vertically aligned and interconnected graphene networks are first used as the filler, which is prepared by a controlled three-step procedure: formation of graphene oxide liquid crystals, oriented freeze casting, and high-temperature annealing reduction under Ar. The obtained composite, at an ultralow graphene loading of 0.92 vol %, exhibits a high thermal conductivity (2.13 W m–1 K–1) that is equivalent to a dramatic enhancement of 1231% compared to the pure matrix. Furthermore, the composite also presents a much reduced coefficient of thermal expansion (∼37.4 ppm K–1) and increased glass transition temperature (135.4 °C). This strategy provides an insight for the design of high-performance composites with potential to be used in advanced electronic packaging.

As a potential energy carrier, hydrogen has surged up the priority list as part of broader decarbonization efforts and strategies to build or acquire a clean energy economy. Driven by...

Closing the carbon-, hydrogen-, and nitrogen cycle with renewable electricity holds promises for the mitigation of the facing environment and energy crisis, along with the continuing prosperity of the human society. Descriptors bridge the gap between the physicochemical factors of electrocatalysts and their boosted activity and serve as guiding principles during the rational design of electrocatalysts. The optimal adsorption strength of key intermediates is potentially accessed under the tendentious guidelines proposed by indicators, such as d-band center, ΔG H , E O* , coordination number (CN), bond length, etc. Here, in this review, a comprehensive summary of the recent advances achieved regarding the descriptors during the rational design of electrocatalysts that aims for the recycling of C/H/N-containing chemicals is offered. The review is initiated by providing the necessity of the development of efficient electrocatalysts and then the physics behind the d-band center is introduced. Then a summary of the recent progress relating to the development of electrocatalysts under the guidance of descriptors is reviewed. Following that, an extended discussion regarding the experimental or theoretical characterization of the d-band center and the descriptors beyond it is provided. Finally, perspectives and challenges in this area are offered.

A room-temperature NO2 gas sensor with excellent performances is fabricated using an MAPbI3 (MA = CH3NH3+) thin film.

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Compact graphene film electrodes with a high ion-accessible surface area have the promising potential to realize high-density electrochemical energy storage (or high volumetric capacitance), which is vital for the development of flexible, portable, and wearable energy storage devices. Here, a novel, ultrafast strategy for stitching graphene sheets into films, in which p-phenylenediamine (PPD) molecules are uniformly intercalated between the graphene sheets, is simply constructed at the ethanol/water interface. Due to uniformly interlayer spacing (∼1.1 nm), good wettability, and an interconnected ion transport channel, the binder-free PPD-graphene film with a high packing density (1.55 g cm) delivers an ultrahigh volumetric capacitance (711 F cm at a current density of 0.5 A g), high rate performance, high power and energy densities, and excellent cycling stability in aqueous electrolytes. This interfacial stitching strategy holds new promise for the future design of enhanced electrochemical energy-storage devices.

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