This paper reports the successful preparation of Mg-doped VO2 nanoparticles via hydrothermal synthesis. The metal-insulator transition temperature (T(c)) decreased by approximately 2 K per at% Mg. The Tc decreased to 54 °C with 7.0 at% dopant. The composite foils made from Mg-doped VO2 particles displayed excellent visible transmittance (up to 54.2%) and solar modulation ability (up to 10.6%). In addition, the absorption edge blue-shifted from 490 nm to 440 nm at a Mg content of 3.8 at%, representing a widened optical band gap from 2.0 eV for pure VO2 to 2.4 eV at 3.8 at% doping. As a result, the colour of the Mg-doped films was modified to increase their brightness and lighten the yellow colour over that of the undoped-VO2 film. A first principle calculation was conducted to understand how dopants affect the optical, Mott phase transition and structural properties of VO2.

The modulation of metal-insulator transition (MIT) temperature and phase stability of thermochromic materials based on all the transition metal doped VO 2 were systematically studied using density functional theory (DFT) calculations. The free energies, formation enthalpies, and Fermi energies of transition metal doped VO 2 were evaluated from DFT calculations; the cell volumes and bulk moduli were obtained by fitting the free energies to the Birch-Murnaghan equation of states; and the decomposition enthalpies and entropies of the transition metal doped VO 2 were calculated using both experimental data and DFT calculations. Based on these results, the MIT temperature was associated with lattice distortion of VO 2 (M 1 ) upon doping, the expansion of cell volume and the decrease in bangle were associated with the decrease in MIT temperature, and the shrinkage of cell volume and the increase in b-angle were associated with the increase in MIT temperature. And it was also concluded that VO 2 (M 1 ) doped with high valence cations is more stable than those doped with low valence cations.These conclusions are consistent with experimental facts that W-, Mo-, and Re-are the most studied and the most effective dopants for the reduction of MIT temperature, and La-, Hg-, and Ag-doped VO 2 undergoes phase separation. In addition, DFT calculations without spin-polarization were also carried out, and the influence of spin-polarization was evaluated. Finally, scandium was proposed as a potential dopant for VO 2 in view of balanced comprehensive performance.

A novel route is proposed for the preparation of mesopore containing zeolite ZSM-5 via in situ hydrothermal treatment of a solution containing alkali-dissolved SBA-15 containing carbonized surfactant P123 in the mesopores; it exhibited prominent stability enhancement for methanol to propylene reaction.

Li-CO2 batteries are widely studied as a promising technology for greenhouse-gas CO2 fixation as well as for energy conversion and storage devices. Their further development, however, is hindered by the refractory discharge products, leading to large polarization voltage and low round-trip efficiency. Here, W2C nanoparticles embedded in the walls of carbon nanotubes (W2C-CNTs) are prepared successfully. An efficient Li-CO2 battery with a W2C-CNTs cathode displays ultralow charge voltage (3.2 V) and high round-trip efficiency (90.1%). The low polarization comes from electron-rich W atoms that break the stable triangle of CO3 2– via W–O bonds. The resulting amorphous discharge products could be readily and reversibly decomposed during charging. Raman and XAS spectra provide direct and solid evidence for the W–O bonds. Also, DFT calculations show there is electron transfer between the W2C surface and Li2CO3, resulting in a low decomposition barrier for Li2CO3 on the W2C substrate.

All-electric switching of perpendicular magnetization is a prerequisite for the integration of fast, high-density, and low-power magnetic memories and magnetic logic devices into electric circuits. To date, the field-free spin-orbit torque (SOT) switching of perpendicular magnetization has been observed in SOT bilayer and trilayer systems through various asymmetric designs, which mainly aim to break the mirror symmetry. Here, we report that the perpendicular magnetization of CoxPt100-x single layers within a special composition range (20 < x < 56) can be deterministically switched by electrical current in the absence of external magnetic field. Specifically, the Co30Pt70 shows the largest out-of-plane effective field efficiency and best switching performance. We demonstrate that this unique property arises from the cooperation of two structural mechanisms: the low crystal symmetry property at the Co platelet/Pt interfaces and the composition gradient along the thickness direction. Compared with that in bilayers or trilayers, the field-free switching in CoxPt100-x single layer greatly simplifies the SOT structure and avoids additional asymmetric designs.

Two series of BN-phenanthrenes, including the parental compounds, have been synthesized in an efficient manner from commercially available materials. Both parental BN-phenanthrenes are strongly fluorescent in solution. Their absorption and emission spectra are greatly dependent on the BN position and orientation. Moreover, the reactivities of the two series of BN-phenanthrenes toward electrophiles are completely different, and these species can be further functionalized by cross-coupling reactions.

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