Lignin-based carbon nanofibrous scaffold: constructing a mechanically robust Bi2WO6/ZnIn2S4 Z-scheme heterojunction membrane for enhanced pollutant degradation and stable cyclability

Recent advancements in sustainable bio-sourced functional materials have focused on enhancing the valorization of lignin-derived biopolymers through innovative transformation methodologies. This study highlights breakthroughs in lignin-based Z-scheme heterojunction photocatalytic systems, emphasizing extended spectral responsiveness, optimized interfacial photoexcited carrier separation and reduced energy loss mechanisms. Two photocatalysts, Bi 2 WO 6 (BWO) and ZnIn 2 S 4 (ZIS) were co-engineered via a Z-scheme charge-transfer pathway using coaxial electrospinning and hydrothermal synthesis with lignin-based carbon nanofibers (CNFs), preserving the fibrous skeleton intact. The all-component photocatalytic nanomembrane exhibited superior mechanical strength (Young’s modulus = 20.38 MPa, toughness = 2.48 kJ/m 3 ) under wet conditions along with accelerated stabilization kinetics (1°C/min, representing a 10-fold increase), resulting in significant energy savings. Using methylene blue (MB) as a model pollutant, the CNFs@BWO/ZIS nanomembrane achieved 94.4% degradation efficiency ( k = 0.01664 min −1 ) after 120 min of solar irradiation, while maintaining excellent recyclability through five successive cycles. Furthermore, we elucidated the systematic mechanism of surface charge-carrier migration in the Z-scheme heterojunction and MB decomposition. This photocatalytic system utilizing sustainable biomass functional materials paves the way for wastewater treatment, with the goal of achieving peak carbon emissions and carbon neutrality. The alternative text for this image may have been generated using AI.