The biochar-based composites were produced using procedures
suggested in previous studies [18,20,22], which all produced large
quantities of biochar/metal oxyhydroxide composites using onestep
pyrolysis. Varying amounts of AlCl3, FeCl3, and MgCl2 hexahydrate
were dissolved in solution with 60 mL of deionized (DI)
water. Five grams of cottonwood was mixed into the solution
and stirred until it was saturated. The mixture was dried