UV–vis-enhanced photothermal catalytic reforming of biomass model tar via LaMnxNi1-xO3 perovskite catalyst

Tar formation during biomass gasification reduces energy efficiency and poses a negative impact on downstream applications. A photothermal steam reforming (PTR) system based on LaMnxNi1-xO3 (0 ≤ x ≤ 1) perovskite was developed to convert tar into combustible gas. The effects of Mn substitution, temperature, and the steam to carbon ratio on PTR activity were investigated. Mn substitution increased the content of surface adsorbed oxygen and maintained the perovskite structure of LaMn0.4Ni0.6O3 (LM4N6). Moreover, LM4N6 showed improved optical absorption and electron-hole separation properties. LM4N6 presented 90 % carbon conversion during PTR at 400 °C. Due to the introduction of ultraviolet–visible light (UV–vis), LM4N6 obtained better catalytic activity and stability in PTR than in the thermal catalytic reforming process. Detailed characterization and experiments proved that UV–vis effectively activated Ni sites and the oxygen species on LM4N6 and formed a photothermal synergistic effect, which inhibited carbon deposition and improved catalytic activity and stability. This work provides a novel concept for the conversion and utilization of biomass tar at low temperatures.