Walnut shell/phenolic resin carbon electrodes via laser sintering and KOH activation

Currently, the application of 3D-printed biomass-based carbon electrodes is hindered by their suboptimal performance. This study utilizes walnut shell powder as a carbon source and employs selective laser sintering technology for the efficient 3D printing of a double-helix carbon precursor. High-performance biomass-based carbon electrodes are prepared through carbonization and potassium hydroxide (KOH) activation. Comparative studies on the microstructure and electrochemical performance of the carbonized and activated samples were conducted. Experimental results demonstrate that potassium hydroxide activation significantly enhances the microstructure of the carbon electrodes, leading to marked improvements in their electrochemical performance. During desalination experiments, the carbon electrodes exhibited excellent ion removal efficiency, with a maximum conductivity reduction rate of 0.2 μS/cm·min, confirming their feasibility in seawater desalination applications. This research validates the potential of walnut shell biomass for the preparation of 3D-printed carbon electrodes, addressing bottlenecks in traditional carbon electrode manufacturing processes while promoting efficient biomass utilization and environmental protection.