Dual/multiphase MWCNT–antimony-doped tin oxide (ATO) nanoparticle composites: an effective covalent fabrication approach

Three innovative preparation pathways for antimony-doped tin oxide (ATO)–multi-walled carbon nanotube (MWCNT) composites have been successfully tested. The designed covalent mode of attachment of both phases, i.e., 10–20 nm-sized ATO nanoparticles (NPs) onto 10–50-μm-long oxidized-MWCNTs (Ox-MWCNTs) and onto polythiophene–MWCNTs (PolyTh–MWCNTs) enabled the preparation of biphasic and triphasic composites, respectively. Triphasic composites made use of poly(thiophene-3-yl-acetic acid) or poly-3,4-ethylenedioxythiophene carboxylic acid polymers covalently grown/grafted onto Ox-MWCNTs, disclosing an outer polyCOOH shell available for later chemical manipulations. The whole set of resulting bi/triphasic ATO-decorated MWCNT composites have been fully analyzed for structural and morphology coherency with emphasis on both quantity and distribution of ATO NPs onto the MWCNT surface. In general, connecting polyTh polymeric phases improved ATO NP dissemination within composites. Moreover, the influence of such polyTh phases on the solid phase conductivity of resulting composites before and after heat sintering (350 °C, 3 h) has been readily investigated using an effective Powder Resistivity Measuring System. Such studies and relevant outputs clearly form a serious basis toward the development of various conductivity-relating applications and/or devices.