Sustainable upgrading of biomass to high-value chemicals is greatly dependent on catalytic C-C/C-O bond cleavage of high selectivity. Here, an oxidation-enhanced photoelectrochemical protocol was developed to be capable of breaking different types of C-C bonds for efficiently producing aromatic carboxylic acids (85.0–99.8% yields) from lignin. Ni local electronic state of the prepared F-Fe 2 O 3 -Co:NiO x H y with excellent durability could be modulated, and high-valence Ni(Ⅳ) reactive species played a key role in the oxidative C-C bond scission of various lignin models. In-situ characterization and control experiments indicated that photocatalytic radical and electrocatalytic interface facilitated C-H/O-H delocalization, contributing significantly to the enhanced oxidation process. In addition, quantum calculations elaborated that photo-excited holes and Ni(Ⅳ) are key reactive species for enhancive electrocatalytic cleavage of different C-C bonds in lignin to exclusively furnish aromatic carboxylic acids. This research provides a renewable funnel strategy for using solar energy to produce high-value mono-functional products from biomass.
Designing efficient catalyst for the oxygen evolution reaction (OER) is of importance for energy conversion devices. The anionic redox allows formation of O-O bonds and offers higher OER activity than the conventional metal sites. Here, we successfully prepare LiNiO 2 with a dominant 3 d 8 L configuration ( L is a hole at O 2 p ) under high oxygen pressure, and achieve a double ligand holes 3 d 8 L 2 under OER since one electron removal occurs at O 2 p orbitals for Ni III oxides. LiNiO 2 exhibits super-efficient OER activity among LiMO 2 , R MO 3 (M = transition metal, R = rare earth) and other unary 3d catalysts. Multiple in situ/operando spectroscopies reveal Ni III →Ni IV transition together with Li-removal during OER. Our theory indicates that Ni IV (3 d 8 L 2 ) leads to direct O-O coupling between lattice oxygen and *O intermediates accelerating the OER activity. These findings highlight a new way to design the lattice oxygen redox with enough ligand holes created in OER process.
危险品化学品经营许可证（带存储）