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SnCdxTe materials were synthesized by the zone-melting method for the thermoelectric performance study. The X-ray diffraction results show that the lattice parameter decreases with increasing x, following the Vegard's law of rock-salt structure SnTe and CdTe. Besides, the room temperature Seebeck coefficients of the SnCdxTe system enhance to > 60 μV/K, larger than those of Cd-doped SnTe synthesized by spark plasma sintering. A large power factor of ~ 25 μW/cmK is achieved in SnCd0.12Te at 820 K, which rivals those of high performance PbTe-based materials. As a result, the highest ZT of ~1.03 at 820 K was achieved for SnCd0.12Te.

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The fabrication of core/shell charged polymer brushes-grafted hollow silica nanoparticles (PSPMA-g-HSNPs) is reported. Because of the excellent hydration capability of the shells consisting of charged polymer brushes, the functional nanoparticles can achieve a good lubricating effect in aqueous media via hydration lubrication mechanism. The mesoporous hollow silica cores endow the nanoparticles with drug loading-release capability. Aspirin, as a useful drug for treating arthritis, was employed to carry out in vitro drug loading and release studies. It is clear that brushes-modified hollow silica exhibited long-term drug release performance. The combination of lubrication and drug loading capabilities results in the great clinical potential of new multifunctional nanoparticles as injectable joint lubricant fluid in arthritis treatment.

Thermoresponsive microgels, poly(N-isopropylacrylamide)-graft-poly(ethylene glycol) (PNIPAAm-g-PEG), were synthesized via emulsifier-free emulsion polymerization and the tribological property as water lubricating additive was studied. The microgels had good thermoresponsive collapse/swelling performance with lower critical solution temperature (LCST) ca. 38.4 °C. The rheological characterization and tribological tests showed that the microgels had a good lubricating performance in aqueous lubrication through interfacial physisorption and hydration lubrication, but the friction coefficient was impacted by temperature (below and above LCST). The tunable thermosensitive tribological property was attributed to the hydrophobic interaction and the enhanced interfacial absorption, which were both triggered by the elevated temperature. Furthermore, in order to avoid the water erosion in aqueous lubrication, the microgels were used together with 1H-benzotriazoles (BTA). Because of the good antifriction and anticorrosion property of BTA and the interplay between microgels and BTA, the microgels/BTA exhibited a synergistic effect in aqueous lubrication and the tribological property was more sensitive around the LCST. The present work is beneficial to understanding the tribological property of responsive microgels in aqueous lubrication and provides a novel approach for achieving low-friction through soft matters.

A novel superhydrophilic material, charged polymer brushes-grafted magnetic core-shell-corona composite nanoparticles (Fe3O4@SiO2@PSPMA), was developed to harvest water through the hydration effect. Because of both the strong hydration capability and the good swelling performance, the negatively charged polymer brushes, PSPMA brushes, endow the composite nanoparticles with superhydrophilicity and a good water-absorbing performance like a sponge, while the magnetic Fe3O4 cores allow easy separation of Fe3O4@SiO2@PSPMA nanoparticles with absorbed water from oil/water mixture under an external magnetic field. The functional particles have the capability of harvesting water droplets whether floating on an oil surface or in the oil. This water-absorbing material uses selective wettability to harvest water and achieve oil-water separation and may be useful in finding novel approaches for recycling water from sewage and removing water in the petroleum industry.

Tin selenite (SnSe) has attracted significant attention due to its record thermoelectric figure of merit (ZT = 2.6 at 923 K) of its single crystal. However, the polycrystalline SnSe processes considerably less ZTs (⩽1.1). In this study, we investigate the thermoelectric properties of Ag-doped polycrystalline SnSe, which was synthesized via zone melting and hot pressing. By comparing our results and previous reports of Ag-doped single crystals and polycrystals, we determine that the high texturing degree is essential for achieving good thermoelectric performance in polycrystalline SnSe. The zone-melted Sn 0.99 Ag 0.02 Se shows better thermoelectric performance than the Ag-doped SnSe single crystal in the entire temperature range, exhibiting a peak ZT of 1.3 at 793 K.

SnSe has attracted increasing attention as a promising thermoelectric material. In this work, a horizontal vapor transfer method was developed to synthesize high-quality, fully dense, and stoichiometric SnSe single crystals, which enables an evaluation of the transport properties inherent to SnSe along the bc-plane. The electronic transport properties can be well-understood by a single parabolic band model with acoustic phonon scattering, enabling insights into the fundamental material parameters determining the electronic properties. The lattice thermal conductivity (κ l ) decreases from 2.0 W m −1 K −1 at 300 K to 0.55 W m −1 K −1 at 773 K. It is revealed that an increase in hole concentration, an involvement of low-lying bands for transport, and a further reduction in κ l would all enable p-type SnSe to be a promising eco-friendly thermoelectric material. This work not only provides a fundamental understanding of the charge transport but also guides the further improvement of thermoelectric SnSe.