RESUMO
Two-dimensional (2D) boron nanomaterials have received considerable attention due to their distinct physicochemical properties in contrast to bulk boron. However, the susceptibility to oxidation in air has limited their practical applications. In this study, we synthesize an environmentally stable bifunctionalized boron nanosheet via a wet chemical route. By lyophilization, we have hierarchically assembled the boron nanosheets into various well-ordered macroscopic forms, which exhibit unique structural features, such as stacking-induced nanochannels for proton transport. The resulting suprastructures show exceptionally high proton conductivity (â¼90 mS cm-1 at 85 °C) and humidity sensitivity (response >40 000% at 97% RH). These findings demonstrate the immense potential of boron nanomaterials in electrochemical applications.
RESUMO
A highly efficient g-C3 N4 photocatalyst is developed by a novel one-pot thermal polymerization method under a salt fog environment generated by heating the aqueous solution of urea and mixed metal salts of NaCl/KCl, namely SF-CN. Thanks to the synergistic effect of the oxygenation and chemical etching of the salt fog, the obtained SF-CN is an oxygenated ultrathin porous carbon nitride with an intermolecular triazine-heptazine heterostructure, meanwhile, shows enlarged specific surface area, greatly enhanced absorption of visible light, narrowed band gap with a lower conduction band, and an increased photocurrent response due to the effective separation of photogenerated holes and electrons, comparing to those of pristine g-C3 N4 . The theoretical simulations further reveal that the triazine-heptazine heterostructure possesses better photocatalytic hydrogen evolution (PHE) capability than pure triazine and heptazine carbon nitrides. In turn, SF-CN demonstrates an excellent visible light PHE rate of 18.13 mmol h-1 g-1 , up to 259.00 times of that of pristine g-C3 N4 .
