A plasma-assisted pulsed heating approach for efficient methane pyrolysis

Plasma-assisted pulsed heating enables non-equilibrium CH 4 pyrolysis. • Decouples CH 4 activation and surface dehydrogenation via temporal control • CO 2 plasma removes carbon deposits and enables catalyst regeneration. Methane pyrolysis is a promising low-carbon alternative to steam methane reforming for hydrogen production, but conventional thermocatalytic approaches are limited by methane activation and high-temperature sintering, leading to low conversion and catalyst deactivation. Here, we develop a plasma-assisted pulsed heating (PPH) strategy that accesses a non-equilibrium reaction regime through dynamic plasma–thermal cycling. This approach uses a bifunctional carbon paper as both the discharge ground electrode and heating resistor to achieve localized, transient, strong electric fields (>3 × 10 6  V/m) and high temperatures (>1500 K). These conditions enable plasma-assisted methane activation and promote surface dehydrogenation by pulsed heating, resulting in high H 2 yield. As a result, PPH achieves 95% CH 4 conversion over a Ni–Fe/SiO 2 catalyst in a 0.1 CH 4 /0.9 He mixture at a pulsed-heating voltage of 46 V and a discharge voltage of 5 kV. Under pure CH 4 conditions, the minimum energy consumption of 27 kWh/kg H 2 , approximately half the typical energy consumption of water electrolysis, is achieved at a pulsed-heating voltage of 46 V and a discharge voltage of 3 kV. Beyond methane pyrolysis, this work establishes a generalizable framework for coupling non-equilibrium plasma chemistry with dynamic thermal control, with implications for chemical manufacturing. Download: Download high-res image (66KB) Download: Download full-size image