Tuning catalyst performance in methane dry reforming via microwave irradiation of Nickel-Silicon carbide systems

The dry reforming of methane (DRM) is a promising route for converting greenhouse gases such as methane (CH 4 ) and carbon dioxide (CO 2 ) into valuable syngas, hydrogen (H 2 ) and carbon monoxide (CO). However, traditional nickel (Ni)-based catalysts suffer from rapid deactivation due to carbon deposition and sintering, especially when supported on low thermal conductivity materials. In this work, a novel post-synthesis microwave irradiation (MIR) treatment is introduced to systematically optimize the performance of Ni – β – SiC and Ni – Ti – Cβ – SiC catalysts for DRM. Unlike previous studies that have used MIR during reaction or with different supports, this approach tunes the metal – support interactions and textural properties of Ni – β – SiC and Ni – Ti – Cβ – SiC catalysts by varying the MIR exposure time after catalyst synthesis. MIR post-treatment (10–25 s) increased the CH 4 conversion to 65 % and the CO 2 conversions to 62 % for Ni–β–SiC catalysts and improved the H₂/CO ratio to 0.80, with stable performance over 20 h. For Ni–Ti–Cβ–SiC, MIR (10–20 s) maintained CH 4 conversion up to 60 % and CO 2 conversion to 58 % over 20 h, while the untreated catalyst, though initially higher, deactivated rapidly. Excessive MIR (30 s) reduced performance for both catalyst types, underscoring the need for optimal exposure time. These findings demonstrate post-synthesis MIR provides a tuneable approach for enhancing both the activity and durability of Ni/SiC – based DRM catalysts through controlled modification of metal – support interactions. This work offers new insights for the design of robust catalysts aimed at greenhouse gas utilization and sustainable syngas production, with activity and stability enhancements linked to controlled changes in metal – support interactions. • Post-synthesis microwave treatment tunes Ni–SiC catalyst activity and stability for DRM. • Optimal microwave exposure boosts CH4 and CO2 conversions while reducing Ni sintering. • Ni–SiC shows enhanced long-term syngas yield and lower coking after MIR optimization • MIR shifts Ni–support interactions, with contrasting effects on Ti–C–SiC versus SiC.