N-doped Nb2O5 nanorods as photocatalyst for enhanced cleavage of C-C bond in lignin models

Lignin has limited potential for transformation into high-value-added chemicals due to the non-polar nature and high bond dissociation energy of its intramolecular C-C bonds. Herein, we synthesized an N-doped Nb 2 O 5 photocatalyst with rod-shaped structure through hydrothermal method followed by calcination for C-C bonds cleavage of β-O-4 type lignin model compound under simulated sunlight. The comprehensive characterization results demonstrated that N doping and the resultant oxygen vacancies significantly enhance visible light response intensity of Nb 2 O 5 , while also altering the valence band and conduction band position. The enhanced reducibility at high conduction band position facilitated the rapid reduction of O 2 to generate superoxide radicals, accelerating the separation of carriers. The N-doped Nb 2 O 5 catalyst achieved 90% lignin conversion, surpassing pristine Nb 2 O 5 (59%), with stable performance over 5 consecutive cycles. This work provides a reference for developing efficient C-C bond selective cleavage photocatalysts through doping strategies.