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Nanoporous materials possess low thermal conductivities derived from effective phonon scatterings at grain boundaries and interfaces. Thus nanoporous thermoelectric materials have full potential to improve their thermoelectric performance. Here we report a high ZTof 1.7 ± 0.2 at 823 K in p-type nanoporous polycrystalline SnSe fabricated viaa facile solvothermal route. We successfully induce indium selenides (InSey) nanoprecipitates in the as-synthesized SnSe matrix of single-crystal microplates, and the nanopores are achieved viathe decompositions of these nanoprecipitates during the sintering process. Through detailed structural and chemical characterizations, it is found that the extralow thermal conductivity of 0.24 W m–1K–1caused by the effective phonon blocking and scattering at induced nanopores, interfaces, and grain boundaries and the high power factor of 5.06 μW cm–1K–2are derived from a well-tuned hole carrier concentration of 1.34 × 1019cm–3viainducing high Sn vacancies by self-doping, contributing to high ZTs. This study fills the gap of achieving nanoporous SnSe and provides an avenue in achieving high-performance thermoelectric properties of materials.

The combination of high strength, great toughness, and high heat resistance for polymeric materials is a vital factor for their practical applications. Unfortunately, until now it has remained a major challenge to achieve this performance portfolio because the mechanisms of strength and toughness are mutually exclusive. In the natural world, spider silk features the combination of high strength, great toughness, and excellent thermal stability, which are governed by the nanoconfinement of hydrogen-bonded β-sheets. Here, we report a facile bioinspired methodology for fabricating advanced polymer composite films with a high tensile strength of 152.8 MPa, a high stiffness of 4.35 GPa, and a tensile toughness of 30.3 MJ/m3in addition to high thermal stability (69 °C higher than that of the polymer matrix) only by adding 2.0 wt % of artificial β-sheets. The mechanical and thermostable performance portfolio is superior to that of its counterparts developed to date because of the nanoconfinement and hydrogen-bond cross-linking effects of artificial β-sheets. Our study offers a facile biomimetic strategy for the design of integrated mechanically robust and thermostable polymer materials, which hold promise for many applications in electrical devices and tissue engineering fields.

Driven by the prospective applications of thermoelectric materials, massive efforts have been dedicated to enhancing the conversion efficiency. The latter is governed by the figure of merit (ZT), which is proportional to the power factor (S2σ) and inversely proportional to the thermal conductivity (κ). Here, we demonstrate the synthesis of high-quality ternary Bi2Te3–xSexnanoplates using a microwave-assisted surfactant-free solvothermal method. The obtained n-type Bi2Te2.7Se0.3nanostructures exhibit a high ZTof 1.23 at 480 K measured from the corresponding sintered pellets, in which a remarkably low κ and a shift of peak S2σ to high temperature are observed. By detailed electron microscopy investigations, coupled with theoretical analysis on phonon transports, we propose that the achieved κ reduction is attributed to the strong wide-frequency phonon scatterings. The shifting of peak S2σ to high temperature is due to the weakened temperature dependent transport properties governed by the synergistic carrier scatterings and the suppressed bipolar effects by enlarging the band gap.

Freestanding and flexible graphene/polyaniline composite paper was prepared by an in situanodic electropolymerization of polyaniline film on graphene paper. This graphene-based composite paper electrode, consisting of graphene/polyaniline composite sheets as building blocks, shows a favorable tensile strength of 12.6 MPa and a stable large electrochemical capacitance (233 F g−1and 135 F cm−3for gravimetric and volumetric capacitances), which outperforms many other currently available carbon-based flexible electrodes and is hence particularly promising for flexible supercapacitors.

We report a simple approach for the direct and nondestructive assembly of multi-sheeted single-walled carbon nanotube book-like macrostructures (buckybooks) with good control of the nanotube diameter, the sheet packing density, and the book thickness during the floating catalytic growth process. The promise of such buckybooks is highlighted by demonstrating their high capacitance and high-efficiency molecular separation by directly using them as a binder-free electrode and as a filter, respectively. Our approach also provides a flexible and reliable way to easily assemble various other types of nanotubes into book-like or even more sophisticated sandwich-like hybrid macrostructures, realizing the shape-engineering of one-dimensional nanostructures to macroscopic well-defined architectures for various applications.