Binary Iron‐Manganese Cocatalyst for Simultaneous Activation of C‐C and C‐O Bonds to Maximally Utilize Lignin for Syngas Generation over InGaN

Solar‐powered lignin reforming offers a carbon‐neutral route for syngas production. This study explores a dual non‐precious iron‐manganese cocatalyst to simultaneously activate both C‐C and C‐O bonds for maximizing the utilization of various substituents of native lignin to yield syngas. By assembling with InGaN nanowires on a Si wafer, the as‐designed dual FeMn cocatalyst affords a measurable syngas evolution rate of 42.4 mol·gcat‐1·h‐1 from native lignin in distilled water with a high selectivity of 93% and tunable H2/CO ratios under concentrated light, leading to a considerable light‐to‐fuel efficiency of 11.8%. The high FeMn atom efficiency arising from the 1‐dimensional nanostructure of InGaN enables the achievement of a high turnover frequency (TOF) of 220896 mol syngas per mol FeMn per hour. By correlating exploration experiments, the critical role of the dual FeMn cocatalyst in the evolving mechanism of lignin and water toward syngas is disclosed at the atomic level. It is discovered that the synergetic iron‐manganese cocatalyst supported by InGaN nanowires enables simultaneous activation of C‐C and C‐O bonds with comparable minimized dissociation energies. This work demonstrates a new and earth‐abundant bifunctional cocatalyst for utilizing various substituents of lignin to produce syngas powered by sunlight beyond fossil fuels.