Thermal nanoconduits inside catalyst particles enable efficient and durable steam methane reforming

Catalyst particles often develop internal temperature gradients – both spatially and between components (active phase vs. support) – that limit rates and accelerate coking and sintering during highly endothermic reactions. We treat intraparticle heat transport as an engineerable design parameter by embedding nanoscale silicon-carbide (SiC) networks within Ni/Al 2 O 3 , creating thermal conduits that homogenize local temperature fields without altering reactor hardware or manufacturing workflows. Finite-element heat-transfer modeling predicts markedly reduced radial temperature gradients for SiC-integrated architectures compared with alumina alone or previously reported core-shell strategies. Experiments in steam-methane reforming (SMR) validate these predictions: embedded SiC increases intrinsic activity (higher turnover frequency) and consistently boosts methane conversion and hydrogen yield versus the SiC-free catalyst, suppresses Ni sintering, and shifts carbon growth from amorphous encapsulating layers to less-deactivating filamentous morphologies, sustaining performance over extended operation. We establish intraparticle thermal management as a general catalyst-design lever that complements compositional and structural optimization.