Liquid-Phase Catalytic Exchange of Hydrogen Isotopes over Ion Sputtering Platinum on Superhydrophobic Coatings

Graphical We proposed a “step by step” strategy of hydrophobic treatment before dispersing Pt nanoparticles to prepare Pt/SSNs/PDMS coating. The Pt/SSNs/PDMS could not only expose more active sites, but also effectively improve the utilization of Pt. The high utilization of Pt nanoparticles improves the economy of the catalysts. Liquid-phase catalytic exchange (LPCE) of hydrogen isotopes has extensive application in upgrading of recycled water and wastewater treatment. This low-temperature catalytic exchange requires hydrophobic catalysts for keeping high exchange efficiency and catalytic stability. To eliminate diffusional influences in conventional porous catalysts, we designed a flat catalyst coating with fully exposed platinum (Pt) active sites by two steps. The hydrophobic coating was firstly established by superhydrophobic silica nanospheres (SSNs) and then Pt nanoparticles were dispersed on the surface of coating by ion sputtering. By adjusting the time of ion sputtering, the catalytic exchange efficiency of optimized catalyst coating (50-Pt/SSNs/PDMS) improved up to 86% at 60 °C and maintained stability for at least 5 h, behaving high catalytic exchange efficiency and good stability. Besides, the turnover frequency of the 50-Pt/SSNs/PDMS was 1.7 times than that of “PDMS+Pt/SSNs” prepared by “glue+power” method. The “step by step” strategy can effectively improve the utilization of Pt and provide a new idea for the preparation of Pt-based hydrophobic catalysts.