La-Doped SmZrO/PU-Coated Leather Composites with Enhanced Mechanical Properties and Highly Efficient Photocatalytic Performance.

Flexible La-doped SmZrO/polyurethane (PU) coated leather composites were synthesized using a one-step hydrothermal method, with highly efficient photocatalytic degradation properties by coating the La-doped SmZrO/PU emulsion onto the leather and drying it. The phase composition and optical properties of the as-prepared photocatalytic material were systematically characterized. The result revealed that La was doped in SmZrO successfully, and the prepared samples still possessed pyrochlore structure. The absorption edge of the prepared samples exhibited a red-shift with the increase in La doping, indicating that La doping could broaden the absorbance range of the La-doped SmZrO materials. The catalytic performance of La-doped SmZrO/PU composite emulsion coating on the photocatalytic performance of leather was studied with Congo red solution as the target pollutant. The results showed that the best photocatalytic property was found in the 5% La-doped SmZrO nanomaterial at a concentration of 3 g/L. The resulting 5% La-doped SmZrO nanomaterial exhibited a high specific surface area of 73.5 m/g. After 40 min of irradiation by a 450 W xenon lamp, the degradation rate of Congo red reached 93%. Moreover, after surface coating, the La-doped SmZrO/PU coated leather composites showed obviously improved mechanical properties, as the tensile strength of La-doped SmZrO/PU coated leather composites increased from 6.3 to 8.4 MPa. The as-prepared La-doped SmZrO/PU coated leather composites with enhanced mechanical properties and highly efficient photocatalytic performance hold promising applications in the treatment of indoor volatile organic compounds.