Rapid Synthesis and Recycling of Carbonized Wood Catalyst Decorated with Co Nanoparticles for High-Efficiency Degradation of Rhodamine B

Abstract

Developing catalysts for purifying organic pollutants in wastewater is significant for environmental remediation. Herein, a high-temperature (1000 K) thermal shock (HTS) method is employed to rapidly synthesize a self-supporting catalyst consisting of cobalt (Co) nanoparticles (NPs) and carbonized wood (CW) within 2 s. Thanks to the porous structure of wood and uniformly distributed Co NPs, the wood catalyst exhibits excellent catalytic activity, achieving over 99% removal of 25 mg L⁻¹ Rhodamine B (RhB) within 10 min using the activated peroxymonosulfate advanced oxidation processes, while the leaching rate of Co ions is less than 1 mg L⁻¹. As a proof of concept, a continuous filter is constructed based on the CW catalysts for efficient RhB degradation in flowing water. With a flow rate of 20 mL min⁻¹, it maintains the removal of over 90% of RhB from wastewater for a duration of 2 h. Benefiting from the rapid synthesis of HTS method, a “deactivation-regeneration” strategy is proposed that extends the recycling cycles of wood catalysts to 20 times, surpassing most reported Co-based catalysts. Derived from renewable wood materials, this catalyst offers advantages of high efficiency, low cost, simple synthesis, and durability, showing great potential for application in various fields including water treatment, electrocatalytic conversion, and energy storage.