In this work, we have synthesized hexapods AgCl crystals with mace pods for the first time. Diallyldimethylammonium chloride (DDA)-controlled stepwise evolution of AgCl crystals from octahedron to hexapods with mace pods are achieved by one-pot method. The intermediates have been captured which show the basic process of crystal growth. In this process, octahedra AgCl crystals firstly grow along the <100> direction and then change to grow in the <110> direction. At the same time, the size of AgCl grow from 2 μm to 20 μm. Due to the poor absorption of visible light by AgCl, sodium borohydride(NaBH4) is used to reduce AgCl hexapods with mace pods crystals. By changing the mole ratio(R) of NaBH4to AgCl, the new structure was reduced to obtain a series of Ag@AgCl microstructures. Visible light catalysis effects of the Ag@AgCl microstructures on degradation of methyl orange (MO) were investigated. The Ag@AgCl microstructures with R = 0.02 have a high photocatalytic performance, which completely degrades MO in 40 min.Keywords:hexapod AgCl;one-pot method;Ag@AgCl microstructure;MO degradation
Jiye Wang,Yazhou Qin,Qiaocui Shi,Luhong Wen,Lei Bi
The controllable preparation of crystals is a prerequisite for exploring their shape-dependent physicochemical properties. Herein, AgCl crystals with different morphologies including octahedron, trapezohedron (TPH), 12-pod and hexapods with mace pods were successfully prepared by a one-pot synthesis method. In the preparation process, ethylene glycol (EG) was used as a solvent and AgNO3 was used as a precursor of Ag+. In particular, the ionic liquid poly(diallyldimethylammonium chloride) (PDDA) not only acted as a Cl− ion precursor but also as a morphology-controlled stabilizer. We further explored the effects of temperature, ligand and precursor concentration on AgCl crystal growth. Moreover, we investigated the effect of Cl− concentration on the morphology of AgCl by adding different amounts of NaCl. We found that under the condition of the lower concentrations of Cl−, {111}-bound octahedral AgCl crystals will transform into TPH enclosed with the {311} facet as the concentration of Cl− ions increases. However, at medium concentrations of Cl−, {111}-bound octahedral AgCl crystals will transform into 3D 12-pod AgCl crystals as the concentration of Cl− ions increases. Under the condition of higher concentrations of Cl−, {111}-bound octahedral AgCl crystals will transform into hexapods with mace pods AgCl crystals as the concentration of Cl− ions increases. According to the experimental results, we proposed the growth mechanism of AgCl microcrystals. This work not only provides a new method for the synthesis of AgCl crystals with a tunable shape, but also helps to understand the crystal growth mechanism.
危险品化学品经营许可证（带存储）