“…350 The functionalized acidic carbons from inexpensive sources, including natural organic carbon matter (such as sugars, carbohydrates, cellulosic materials, and lignin), have been achieved by several researchers. 341,[351][352][353] Besides this, agro waste such as husk, straw, seed cover, cow manure, corn cob, 342,343,354,355 carbonaceous waste from industries (char, oil pitch, coke, glycerol) 346,348,356,357 and polymer resins 349,358,359 were also used. Various carbon supports (e.g., zeolite-templated carbons, mesoporous carbons, active carbon) 352,353,360,361 and more recently nanostructured carbons (such as graphene, graphene oxide, carbon nanotubes, and carbon dots) 362-367 have been exploited for the same purpose.…”