The pyrolysis behavior and biochar characteristics of Jerusalem artichoke straw with cerium nitrate

The pyrolysis behavior of Jerusalem artichoke straw with cerium nitrate was analyzed by thermogravimetric analyzer coupled with Fourier-transform infrared spectroscopy. Then the cerium oxide doped biochar was ob-tained from the pyrolysis of Jerusalem artichoke straw impregnated with cerium nitrate. And the electrochemical characteristics and physical structures of the cerium oxide doped biochar from different pyrolysis temperatures were analyzed. TG results showed that the addition of cerium nitrate reduced the reaction energy and pyrolysis temperature, facilitating the pyrolysis reaction. FTIR results revealed that H2O, CO2, CO, CH4, C-O, C--O, and aromatic C--C were released during the pyrolysis. The cyclic voltammetry curves, galvanostatic charge-discharge curves, and electrochemical impedance spectroscopy curves of the electrode modified with cerium oxide doped biochar indicated that the biochar derived from higher pyrolysis temperature showed a better enhancing effect for electrochemical properties. Nanostructured cerium oxide was observed on the surface rather than in the pores of biochar. The existence of a crystalline structure with a mixture of Ce3+/Ce4+ oxidation states further confirmed the formation of nanostructured cerium oxide. The finding revealed that cerium oxide doped biochar composites showed the potential for a wide application in electrochemistry.