Effect of external electric field on the adsorption of ethylene oxide on pristine and Al-doped coronenes: A DFT study

The adsorption interactions between ethylene oxide (EO) molecule and pristine and aluminum-doped coronene (Al-coronene) were studied in the presence and absence of perpendicular external electric fields (EFs) with strengths [Formula: see text], [Formula: see text] and [Formula: see text] a.u. using density functional theory (DFT) calculations. The geometry optimizations and adsorption calculations were carried out by employing 6-31[Formula: see text]G** basis set. The changes in geometric and electronic structures after the adsorption were investigated to characterize the sensitivity of pristine and Al-coronene toward EO molecules. For all the studied systems, adsorption energies ([Formula: see text], band gap energy ([Formula: see text], Mulliken charge transfer, molecular electrostatic potential (MEP) and density of electron state (DOS) were calculated and discussed. According to the obtained results, the high impact of the applied EFs on the adsorption characteristics of EO molecules on the pristine and Al-doped coronenes showed that applying EF is a good strategy for enhancing the EO adsorption capability of the pristine and Al-doped coronenes, improving the potential application of coronene-based sensors for detection of EO in trace amounts.

Integrating AgI/AgBr biphasic heterostructures encased by few layer h-BN with enhanced catalytic activity and stability

Using freshly prepared water-soluble KBr crystal as facile, low-cost sacrificial template, AgBr nanocubes were synthesized through one-pot precipitation method, then navy bean shaped AgI/AgBr biphasic heterostructures were synthesized through anion-exchange reaction and encased within few-layer h-BN to obtain final product. The obtained heterostructured AgI/AgBr/h-BN composite without plasmonic noble metal nanoparticles was used as stable and high active photocatalyst for dye degradation under visible light irradiation, comparing both with self-prepared normal AgBr, AgBr cubes, AgI/AgBr navy beans and other related catalysts reported in the literature. The significant boosting of activity was attributed to the formation of AgI/AgBr interface and the coupling of few-layer h-BN, the latter of which not only effectively suppresses the reduction of silver ions but greatly enhance the charge separation. Furthermore, it was suggested that the photogenerated holes and superoxide radical were the main active species according to photoelectron chemical measurements, electron spin resonance spin-trap analysis and radical trapping experiments. Finally, the possible mechanism of enhanced photocatalytic activity and stability was discussed and proposed. The work demonstrates that engineering Ag-based semiconductor coupling with h-BN would profit the design strategy for low-cost, solar-driven photocatalysts.

Microwave-assisted rapid synthesis of graphene-analogue hexagonal boron nitride (h-BN) nanosheets and their application for the ultrafast and selective adsorption of cationic dyes from aqueous solutions

Graphene-analogue hexagonal boron nitride (h-BN) nanosheets are successfully synthesizedviaa facile and fast microwave-assisted method in 10 min and used as a novel adsorbent for the ultrafast removal of cationic organic dyes in aqueous solution.