Lignin is a promising feedstock for production of aromatic compounds and green energy. Here, based on cobalt-based bifunctional electrocatalysts, we have developed a new coupled system for efficient transformation of lignin to electricity, aromatic aldehydes and H2. A facile approach for preparing nanoflower-like catalysts has been developed by using high-current density electrodeposition of Co on Ni foam. The obtained electrode showed excellent performance for converting lignin to electricity in a direct lignin fuel cell (DLFC), and electro-oxidation of lignin to obtain aromatic aldehydes, as well as hydrogen evolution reaction in an electrolytic cell. The peak power density of the DLFC reached 196.1 mW‧cm–2. By using the DLFC as a power supply for lignin depolymerization and HER, endogenous electrons of lignin could be well transferred to water, resulting in formation of aromatic aldehydes and H2 without input of external electricity. The total aromatic aldehyde yields at the anodes of DLFC and the electrolytic cell were 2.90% and 3.34%, respectively, and the H2 production at the cathode of the electrolytic cell was 12.7 mL‧cm–2. This work thus can provide a novel system for lignin valorization and sustainable production of hydrogen.
