Synthesis, Characterization, and Microwave Absorption Property of the SnO2Nanowire/Paraffin Composites

In this article, SnO2nanowires (NWs) have been prepared and their microwave absorption properties have been investigated in detail. Complex permittivity and permeability of the SnO2NWs/paraffin composites have been measured in a frequency range of 0.1–18 GHz, and the measured results are compared with that calculated from effective medium theory. The value of maximum reflection loss for the composites with 20 vol.% SnO2NWs is approximately −32.5 dB at 14 GHz with a thickness of 5.0 mm

Engineered pigment nanoparticles: bottom-up synthesis, characterization, and performance properties

High performance organic nanopigments are an increasingly important class of functional nanomaterials that possess physical properties ranging between molecular and bulk materials. These nanomaterials have been utilized in a variety of important commercial applications including coatings, printing, information storage, and display technologies [1]. We will discuss our recent work in developing a bottom-up approach for preparation of 3 different classes of high-performance organic nanopigments: 1) azo-laked Pigment Red 57:1 (LAK), 2) quinacridone Pigment Red 122 (QUIN), and 3) azobenzimidazolone (BZI) Pigments Yellow 151 and Red 175. The physical characteristics of the nanopigments were characterized by electron microscopy, dynamic light scattering (DLS), and powder X-ray diffraction (XRD), while their coloristic spectral properties, and dispersion thermal stability were investigated in various matrices. We identified relationships between pigment particle size and their coloristic as well as thermal stability properties for these nanopigments. High resolution transmission electron microscopy (HR-TEM) provided clear images of lattice fringes, and enabled us to determine the crystal orientation of the molecules packed within the QUIN and BZI pigment nanoparticles.Peer reviewed: YesNRC publication: Ye