Crack Formation on Crystalline Bismuth Oxychloride Thin Square Sheets by Using a Wet‐Chemical Method

Abstract

The morphology of nanocrystals is crucial in modulating their properties including optical, chemical and catalytic ones. For the intensively studied sheet-like structures, it is also important to engineer their detailed nanostructures on sheet surfaces. In this work, micron-sized bismuth oxychloride (BiOCl) thin square sheets in tetragonal matlockite-like phase and the corner-truncated ones were successfully synthesized by using a simple wet-chemical method. These square sheets could be partially etched, forming surface cracks with the size and density easily tuned. Two different types of cracks were observed on the surfaces of the corner un-truncated and truncated BiOCl square sheets. Surprisingly, radial cracks formed on the corner-truncated BiOCl sheets, which is attributed to the existence of physical stress during the etching and is highly related to the original nanostructure of the BiOCl sheets. This work provides a wet-chemical method for engineering surface cracks, especially radial cracks, on the surfaces of BiOCl nanosheets, which may be expanded to surface engineering of other nanosheets and will show a great potential in various fields. Nanocrystals, especially semiconductor ones, usually possess unique chemical, electrical, optical and magnetic properties compared to their bulk counterparts. [1][2][3][4][5][6] These properties are highly dependent on the chemical composition, size, shape and surface state of the nanocrystals. [3,[7][8][9][10][11] Therefore, controlled synthesis of nanocrystals is becoming a hot topic in many fields, and lots of efforts have been made to precisely control the morphology and surface state of the nanocrystals. [9,[12][13][14][15][16][17] Among various shaped nanocrystals, the sheet-like ones show promising properties and applications due to their structural simplicity, large surface area, easy charge separation, etc. [18][19][20][21] Sheet-like [a] R.

Modulating the Plasmon-Mediated Oxidation of p-Aminothiophenol with Asymmetrically Grafted Thiol Molecules

“…In analogy to the valence band (VB) and conduction band (CB) in a semiconductor, , the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) exist in an organic molecule, which can be easily adsorbed or grafted onto the surface of a plasmonic metal via physical interaction or chemical bonding. Therefore, adsorbing or grafting molecules on a plasmonic metal may become an effective way for modulation of the charge separation and plasmon-mediated chemical reactions.…”

Molecular Cocatalyst-Induced Enhancement of the Plasmon-Mediated Coupling of p-Nitrothiophenols at the Silver Nanoparticle–Graphene Oxide Interface

“…As important chemical reagents, aromatic azo compounds are widely used in industrial production of dyes, food additives, drugs, free radical initiators, and optical electronic components. − Traditionally, aromatic azo compounds are synthesized via transition-metal-catalyzed oxidation of aromatic amines. , However, the yield is low, and the toxic and harmful reagent of nitrous acid is used, unfriendly to the environment. , Recently, aromatic azo compounds have also been synthesized via plasmon-mediated reduction of nitroaromatic compounds at high efficiency − because of the high absorption coefficient and utilization efficiency of light in plasmonic nanostructures. − However, the potential of plasmonic nanostructures in chemical reactions is still not fully explored due to the limited lifetime of the plasmon-generated hot carriers. − It is necessary to develop new strategies to further enhance the rate and efficiency of the coupling reaction of nitroaromatic compounds.…”

Plasmon-generated hot holes for chemical reactions

“…Fujishima and Honda first realized the water splitting under solar illumination by using titanium dioxide (TiO2) as photocatalyst [6]. Since then, many semiconductor-based photocatalysts have been developed for photochemical reactions [7,8]. However, these semiconductor catalysts are usually limited by the large band gap (only ultraviolet and short wavelength visible light could be utilized) and the poor photo or chemical stability.…”