Synthesis and Characterization of Layered Perovskite-type Organic-inorganic Hybrids(C_nH_(2n+1)NH_3)_2(CH_3NH_3)_(m-1)Pb_mI_(3m+1)(n=5-10,m=1,2)

Layered organic-inorganic hybrids(C_nH_(2n+1)NH_3)_2(CH_3NH_3)_(m-1)Pb_mI_(3m+1) containing monolayer(m=1) and bilayer(m=2) perovsikte were synthesized by reactions in solution.The influences of the reactant ratio,solvent,reaction temperature,and reaction time on the structures of the products were investigated.The structures and the properties of the hybrids were characterized using X-ray diffraction(XRD),scanning electron microscopy(SEM),and ultraviolet and visible(UV) absorption spectroscopy.The XRD patterns and the SEM images demonstrate that the pure bilayer perovskite hybrids are obtained.The UV-vis spectra indicate that the number of the inorganic perovskite layer(m) has greater impact on the band gap than the number of the carbon atoms(n).The band gap of bilayer hybrids(around 1.9 eV) is significantly less than that of monolayer hybrids(around 2.2 eV).