Graphene oxide for cellulose hydrolysis: how it works as a highly active catalyst?

Abstract

Graphene oxide (GO-ene), the two-dimensional carbon lattice decorated by abundant oxygen functionalities, is demonstrated as an efficient green catalyst towards selective hydrolysis of cellulose to glucose. The synergy of its carboxylic/phenolic groups and its layered, soft structure rendered GO-ene superior hydrolytic activity.

Chemocatalytic hydrolysis of cellulose into glucose over solid acid catalysts

“…Following their work, a great many of carbonaceous solid acid catalysts, which are generally prepared by the incomplete carbonization of natural organic matters and the subsequent sulfonation of the resulting amorphous carbons in the presence of concentrated sulfuric acid, fuming sulphuric acid or chlorosulfonic acid [186][187][188][189][190][191][192][193][194][195], have been designed for the hydrolysis of cellulose. For example, in 2008 and 2014, Onda et al [140] and Zhao et al [49] prepared an active carbon-(AC-SO 3 H) and a graphene oxide-based (GO-ene) solid acid catalysts, resulting in 40.5% and 49.9% glucose yields in aqueous solution at 150 • C for 24 h, respectively. In 2012 and 2013, glucose-(GC-SO 3 H) and sucrose-derived (SC-SO 3 H) solid acid catalysts were also synthesized by Guo et al [196] and Liu et al [197], and when they were applied in the presence of [BMIM]Cl, the yields of TRS with 72.7% and 71.0% were obtained at 110 • C and 120 • C for 4 h, respectively.…”

“…Sulfuric acid (H 2 SO 4 ), nitric acid (HNO 3 ), perchloric acid (HClO 4 ), phosphoric acid (H 3 PO 4 ), hydrochloric acid (HCl), hydrofluoric acid (HF) and formic acid (FA) are known as a typical type of homogeneous acids [40][41][42][43][44][45][46][47][48]. Although they exhibit reasonable prices and good catalytic activities, their practical applications are difficult due to a lot of problems including reactor corrosion, waste treatment and poor recyclability as well as severe reaction temperature [49][50][51][52][53][54]. In contrast to homogeneous acids, cellulases that can be derived from Trichoderma reesei, Aspergillus niger, Aspergillus nidulan and Penicilinium funiculosum are more selective and competitive to hydrolyze cellulose into glucose at lower reaction temperature [55][56][57][58][59].…”

Depolymerization of Cellulosic Biomass Catalyzed by Activated Carbons

“…In addition, good yields of glucose (50-60 %) were obtained by using graphene oxides, but graphene oxides became black precipitates having low activity after the reaction. The reaction temperature of 503 K is high enough to decompose oxygenated groups of graphene oxide to CO and CO 2 [ 11 ], which induce its aggregation. Thus, we studied the catalysis of more typical carbon materials for the hydrolysis of cellulose.…”

Electrocatalytic Oxidation of Cellulose to Gluconate on Carbon Aerogel Supported Gold Nanoparticles Anode in Alkaline Medium

“…From Figure S4, a band at~1631 cm´1 is observed occurring in the spectrum of HNO 3 activated CA, assigned to -COO´group [30]. According to the references [9,31,32], surface oxidized carbons are promising water-tolerant materials that also demonstrated high catalytic performance for hydrolysis of cellulose or cellobiose. This might be attributed to its favorable adsorption to oxygen atoms of the 1-4-glycosidic bonds in cellulose molecules, so as to benefit the catalytic performance.…”