Layered α-TiCl3: Microsheets on YSZ substrates for ethylene polymerization with enhanced activity

The transition metal halide α-titanium(III) chloride (α-TiCl3) is a layered two-dimensional compound and a well-established Ziegler-Natta catalyst for the polymerization of ethylene. A new synthesis technique is used to obtain thin sheets of α-TiCl3 that show exceptional physical properties in contrast to their bulk counterparts, due to an enlarged surface-to-volume ratio. Chemical vapor transport (CVT) of α-titanium(III) chloride directly on substrates results in microsheets that exhibit an improved catalytic effect. For rational planning of synthesis conditions, thermodynamic simulations of occurring gas phase equilibria were performed. Based on these calculation results, crystal growth succeeded by adding GaCl3 via pure short term CVT in a temperature gradient of 700 K to 600 K on yttrium-stabilized zirconia (YSZ) substrates. Phase pure, as-grown, single crystal sheets with high crystallinity and thicknesses of around 4 µm were obtained. These thin sheets of α-TiCl3 on YSZ substrates were implemented a...