ABSTRACT
Single crystals of PbS in the form pyramids with a high proportion of high energy {331} faces are obtained by the use of a novel reaction technique at the interface of water and toluene. The pyramids spontaneously form a monolayer spread across the entire water-toluene interface. The influence of deposition parameters such as temperature, solution concentration, reaction time on the nature and properties of interfacial films are studied. In addition, the effect of solvo-static parameters such as column height and interfacial area are investigated. The obtained films are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM).
ABSTRACT
A new, generic method to exercise control over the shape of crystallites is reported. Crystals of PbS are grown in the unusual form of pyramids at the water-toluene interface. The pyramids are single crystalline and adopt a unique growth habit (slow growth along [113] direction). The pyramids are exclusive products of the reaction and are obtained in the form of a monolayered film spread across the fluid interface. The origins of the growth habit and assembly lie in phenomena unique to the liquid-liquid interface. The dimensions of the pyramidal base can be controllably varied in the range 575-1260 nm. Crystallites of other forms such as rods and spheres can be obtained by varying the properties of the fluid interface.
Subject(s)
Energy Transfer , Lead/chemistry , Sulfides/chemistry , Crystallization , Microscopy, Electron, Scanning , Molecular Structure , Particle Size , Solutions/chemistry , Sulfides/chemical synthesis , Surface Properties , Toluene/chemistry , Water/chemistryABSTRACT
The synthesis of thin films and nanocrystalline matter at the interface of two liquids is emerging as an important area in synthesis of inorganic materials. The advances in this area are reviewed to highlight potential uses of this method. The current understanding of the deposition process is discussed.