The Nature of the Isolated Gallium Active Center for Propane Dehydrogenation on Ga/SiO2

Single-site Ga/SiO 2 catalysts exhibit up to 99% C 3 H 6 selectivity at 4% propane conversion with an initial rate of 5.4 × 10 −4 (mole C 3 H 6 ) (mole Ga) −1 s −1 during propane dehydrogenation (PDH) at 550 °C. Following pre-treatment in H 2 at 550 °C, only four-coordinate, Ga 3+ –O Lewis acid sites are observed under reaction conditions. At 650 °C in H 2 , an additional isolated Ga site with lower Ga–O coordination ( N Ga−O