Coassembly of exfoliated Ni-In LDHs nanosheets with DNA and infrared emissivity study

摘要

The biomolecule-inorganic hybrid materials are potential candidates for low infrared emissivity materials due to the combined functionalities of the biomolecules and the inorganic components. In this study, we describe a facile approach to fabricate DNA/layered double hydroxides (LDHs) nanohybrid by coassembly of exfoliated Ni-In LDHs nanosheets with DNA. In the assembly progress, exfoliated LDHs nanosheets and DNA with different initial DNA/LDHs mass ratio were mixed together, and the DNA intercalated LDHs nanohybrid was obtained only when the input DNA/LDHs mass ratio is ≤0.3 mg/mg. The structure and morphology of as-fabricated hybrid materials were characterized by X-ray diffraction (XRD), UV-Vis absorption spectra, Fourier transform infrared (FT-IR) spectra, thermogravimetry (TG), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results indicate that the reassembled product has layered structures incorporated with DNA biomolecule. The nanohybrid with expanding LDHs structure of d_(003) = 2.6 nm confirms the intercalation of DNA molecules into the LDHs interlayer. The helix chain oriented parallel to the basal plane of host layer forming ordered sandwich structure. The infrared emissivity value of the DNA/LDHs nanohybrid was then investigated. It was found that the infrared emissivity values were significantly reduced by coassembly of exfoliated LDHs nanosheets with DNA, which may be attributed to the synergistic effect and interfacial interaction between the DNA biomolecule and inorganic LDHs layers reinforced by the construction of ordered sandwich structure.