Magnetic field-enhanced catalytic mechanism for green syngas production from phenolic tar in biomass pyrolysis

Magnetic fields (MFs) present a promising strategy for enhancing catalytic performance in biomass tar reforming, though their underlying mechanisms remain incompletely understood. This study systematically investigated MF-induced enhancement of Ni-based catalysts for phenol cracking through integrated density functional theory (DFT) calculations and experimental validations. DFT calculations demonstrated that MF intensification induced an upshift in the Ni 3d-band center, enhanced orbital hybridization, and promoted electron transfer from Ni active sites to phenol molecules, consequently suppressing oxygen vacancy deactivation. Transition-state analysis revealed that MF optimized phenol adsorption configurations and reduced reaction energy barriers, facilitating radical-driven pathways. Experimental results showed that under an 80 mT MF at 700 °C, the Ni/CaO-Ca12Al14O33 catalyst achieved 98.7 % phenol conversion (a 33.2 % enhancement), with H2 and CO yields increasing by 25.1 % and 60.7 %, respectively, while CO2 emissions decreased by 37.5 %. Spectroscopic analyses (XPS, EPR) confirmed MF-mediated electron redistribution and oxygen radical suppression. These findings provide fundamental insights into MF-enhanced catalysis and advance the development of efficient, low-carbon biomass conversion technologies.