The interaction between negatively charged all-inorganic silicon quantum dots (Si QDs) and bovine serum albumin (BSA) is studied. It is shown that a small difference in the size of Si QDs affects the structure of Si QD–BSA composites significantly. When the diameter of Si QDs is 4 nm, a heterodimer (~20 nm) composed of one Si QD and one BSA molecule is a preferable and stable structure. On the other hand, when the diameter is 7 nm, the size of the composites increases to ~50 nm. The Si QD–BSA composites exhibit stable photoluminescence in the near-infrared range in phosphate-buffered saline.

To improve the stability of Cs2SnCl6 under aqueous/moisture environments, we applied a concept of artificial passivation by depositing a protective TiO2 coating of 10 nm on the surface of Cs2SnCl6. Static leaching experiments results indicate that the initial release rates of Cs+ and Cl− are decreased by 20–30 times with TiO2 coating, suggesting its possibility to improve the short-term water/environmental stability of Cs2SnCl6. An amorphous-to-crystalline phase transition in TiO2 film was observed, possibly resulting in degradation of Cs2SnCl6. However, the crystalline TiO2 film still remains after 21 days water exposure and can still act as an effective passivation layer to reduce the release rates of Cs+ and Cl- by as much as about 17 and 7 times, respectively, relative to static leaching without artificial coatings. Therefore, the water/environmental stability of metal halide perovskite Cs2SnCl6, which is a highly soluble molecular salt, can be enhanced by the nanoscale TiO2 coating as an artificial passivation film.

Thermal transport of pillared-graphene structure (PGS) supported on a copper substrate was investigated using equilibrium molecular dynamics. The results show that thermal conductivity along the graphene sheet in Cu-supported PGS ranges between 96.12 and 247.16 W/m K for systems with different dimensions at an interaction strength χ = 1. Thermal conductivity along carbon nanotube was found to range between 22.43 and 30.83 W/m K. The increase of interaction strength between Cu and carbon leads to a general decrease in thermal conductivity of PGS. The simulation results suggest that the thermal conductivity in Cu-supported PGS systems is governed by system geometry and phonon transport.