Nb2O5 plays a unique role in supported metal catalysts for lignin hydrodeoxygenation. As a support material, Nb2O5 improves the dispersion and prevents sintering of metal nanoparticles during lignin hydrodeoxygenation. Studies have shown that Nb2O5 supported metal catalysts such as Ru/Nb2O5 and NiMo/Nb2O5 have higher activity and stability for lignin hydrodeoxygenation compared to catalysts without Nb2O5.