A defect-complementary strategy for breaking the trade-off between gas permeance and catalytic activity in SiC catalytic membranes

Silicon carbide (SiC) catalytic membranes are promising for the simultaneous removal of NO and particulate matter from industrial flue gas, but catalyst-induced pore narrowing creates a trade-off between gas permeance and catalytic activity. Herein, we focus on pore-structure predesign and propose a defect-complementary strategy integrating particle-penetration suppression with catalyst-induced pore regulation. Large SiC particles were used to fabricate an enlarged-pore membrane without an intermediate layer, preventing particle penetration into the support and simplifying preparation. Subsequent controlled loading of VCeTi catalyst narrowed the enlarged pores to the desired size while introducing NH 3 -SCR functionality. This complementary pore-design strategy achieved high gas permeance and high catalytic activity by offsetting the initially enlarged pores with the catalyst-induced pore-narrowing effect, thereby breaking the permeance–activity trade-off. The optimized V/SiC-N50 catalytic membrane exhibited an average pore size of 9.9 μm and achieved 26% higher gas permeance than the conventionally prepared V/SiC-W40 membrane, together with over 90% NO removal efficiency at 250–430 °C and 99.99% PM 2.5 filtration efficiency. Moreover, the strategy was successfully extended to tubular catalytic membranes, demonstrating its scale-up potential. In summary, this work provides a novel strategy for fabricating high-performance SiC catalytic membranes and establishes a design paradigm extendable to other fields.