Electrocatalytic and Photocatalytic Approaches to Lignin Conversion

Solar energy driven C–C bond cleavage in a lignin model compound with a D–π–A organic dye-sensitized photoanode

“…Fluorine-doped tin oxide glass was purchased from Hartford Glass Co., Inc. Tetrabutylammonium hexauorophosphate (TBAPF 6 ) was purchased from TCI. 9-Azabicyclo [3,3,1]nonan-3-one-9-oxyl was purchased from Sigma-Aldrich. The LMC, 1-(4-hydroxy-3,5-dimethoxyphenyl)-2-(2-methoxyphenoxy)propane-1,3-diol, was purchased from SY Innovation and used without further purication or modication.…”

“…Lignin is one of the most abundant natural aromatic resources on Earth and is recognized as a potential feedstock for alternative fuels and chemicals. 1 Lignin valorization requires a cost effective means of driving the energy intensive conversion of lignin to value-added monomeric chemicals (e.g., vanillin, catechol, and phenol) that are important raw materials for the production of bioplastics, adhesives, and pharmaceuticals. [2][3][4][5][6][7][8][9] In addition, lignin is reported as a precursor for a polymeric composite that can be used for various energy applications.…”

Enhanced Photocatalytic Alcohol Oxidation at the Interface of RuC-Coated TiO2 Nanorod Arrays

“…Lignocellulosic biomass including cellulose, hemicellulose, and lignin represents a potential substitute for petroleum-based carbon sources by converting to value-added fuels and commodity chemicals. , Lignin valorization through conversion to low-molecular-weight aromatic compounds has been considered as a sustainable alternative source to petroleum for the chemical industry. , Recent studies for lignin valorization have focused on chemical, electrochemical, and/or photocatalytic strategies for depolymerization under mild conditions to produce well-defined and targeted value-added aromatic chemical building blocks. − In particular, oxidation of the 2° benzylic C α –OH alcohol in the β-aryl ether linkage, which is the most abundant linkage in lignin, is a critical step toward cleaving the lignin polymer backbone to produce targeted aromatic compounds. Previous studies have reported the chemical, electrochemical, or photoelectrochemical oxidation of the benzylic C α –OH group in lignin model compounds with the use of nitroxyl radicals (e.g., 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO), N -hydroxyphthalimide (NHPI)) as a hydrogen atom transfer mediator (HAT) (Figure ).…”