Oriented-aggregation of organic organization: Morphology-controllable synthesis,surface photovoltage spectroscopy and morphology-dependent optical property

Assembled ZnQ₂·2H₂O microstructures, such as microsheet, sandwich-like structure and hexangular microflake, have been successfully prepared in CTAB microemulsion system through the stacking of ZnQ₂·2H₂O molecules and oriented aggregation of ZnQ₂·2H₂O original building blocks. Controlled experiments demonstrated that the morphologies of building block and final product could be readily tuned by reaction parameters, and a formation mechanism, involving re-precipitation, growth and oriented aggregation process, has been proposed on the basis of time-dependent experimental results. The obtained products were carefully characterized by X-ray powder diffraction (XRD), thermal gravimetric analysis (TGA), transmission electron microscope (TEM), field-emission scanning electron microscope (FESEM), FT-IR spectrum, UV–vis spectrum and photoluminescence (PL) spectrum. The surface photovoltage (SPV) of the obtained ZnQ₂·2H₂O microstructures was investigated by means of surface photovoltage spectroscopy (SPS) and field-induced surface photovoltage spectroscopy (FISPS). The SPS and FISPS revealed that the photogenerated charges of ZnQ₂·2H₂O could be separated distinctly and ZnQ₂·2H₂O possessed p-type semiconductor characteristics, respectively. Furthermore, UV–vis and PL spectra evidenced the optical properties of ZnQ₂·2H₂O were sensitive to its microstructure or morphology.