Core-shell carbon-ceramic fibres by electrospinning and atomic layer deposition (ALD)

Electrospinning can be used to prepare submicron polymeric or composite fibres. Such fibres can be as precursors and subsequently pyrolysed into carbon fibres. The small fibre diameter, small pore size, and high surface area of the nanofibre web are properties that are advantageous for various applications including catalysis. In this study we prepare corrosion resistant and electrically conductive catalyst support structures utilizing electrospinning. In this presentation we present first results of the study carried out within project Catapult (novel CATAlyst structures employing Pt at Ultra Low and zero loadings for auTomotive MEAs; Supported by EU FCH-JU; Grant agreement no 325268). Our approach to produce core-shell carbon-ceramic catalyst supports include preparation of electrospun precursor fibres, stabilization and carbonization of precursor fibres into carbon, and atomic layer deposition (ALD) coating method to produce semi-conducting oxide layer onto carbon fibres. Electrospun fibre sheets are prepared from polyacrylonitrile (PAN) and mixture of PAN and carbon nanotubes (CNT) with lab scale electrospinning setup equipped with rotating drum collector in dry atmosphere. Stabilization and carbonization of web samples are carried out using tubular furnace suitable for roll-to-roll operation, and carbon samples are coated with niobium doped titanium oxide in ALD batch reactor. Conductivities of carbon fibres and ALD coated carbon fibres were around 5-20 S/cm.