Lignin-derived carbon as rapid charge-transfer bridge for efficient solar-driven H2O2 production over CN/Mxene heterojunction

Graphitic carbon nitride (g-C3N4, 3 N 4 , CN) has been recognized as an environmentally friendly, and promising photocatalyst, particularly for solar-driven synthesis of hydrogen peroxide (H2O2). 2 O 2 ). Heterostructure engineering to decorated CN is an effective approach for boosting photocatalytic H2O2 2 O 2 production. However, the current challenge lies in the efficient transmission of interfacial charge carriers. Herein, we propose a breakthrough approach to synthesize g-C3N4/Mxene 3 N 4 /Mxene (CNM) M ) composites with lignin-derived carbon (L) as a bridge for electron transfer. The optimal ternary heterojunction (CNM,L) M,L ) demonstrated its impressive performance (0.75 mmol/L) for photocatalytic H2O2 2 O 2 production, which was three times higher than that of pristine CN. The significance of lignin-derived carbon in g-C3N4/Mxene 3 N 4 /Mxene composites not only improves light adsorption, but also promotes electron transfer between the interfacial g-C3N4 3 N 4 and Mxene during the oxygen reduction reaction (ORR) process for H2O2 2 O 2 evolution. This work provides an eco-friendly design of lignin-derived carbon, which efficiently tunes the photo-generated charge transfer of CN-based photocatalysts for H2O2 2 O 2 generation.