3D printed hierarchically porous zero-valent copper for efficient pollutant degradation through peroxymonosulfate activation

Abstract

Three-dimensional (3D) printing has demonstrated great potential in wastewater purification. Herein, a facile 3D printing strategy is utilized to prepare zero-valent copper (3D-ZVC). The obtained 3D-ZVC framework displays a hierarchically porous structure and a rough surface, which correspond to excellent mechanical robustness and catalytic performance in degrading multiple organic pollutants through peroxymonosulfate (PMS) activation. The 3D-ZVC/PMS/Vis system is capable of achieving a tetracycline (TC) degradation efficiency of over 96.5 % within 20 min, which greatly exceeds that of homogeneous Cu2+/PMS/Vis and contemporary powder/PMS/Vis systems as a result of the unique hierarchical porous structure and cycling of Cu(I)/Cu(II) in 3D-ZVC. Furthermore, the 3D-ZVC/PMS/Vis system exhibits a broad pH resistance range (3.21–10.18), spectacular adaptability, unparalleled stability, and excellent reusability after 23 successive cycles. Electrons and various reactive oxygen species, including SO4−, OH, O2−, and 1O2, are all involved in the decomposition of TC, with 1O2 playing a dominant role. The influence parameters and possible intermediates of the 3D-ZVC/PMS/Vis system are investigated. Toxicity estimation analysis indicates that the toxicity of TC degradation products has been significantly reduced, which is further confirmed through growth control experiments of bean sprouts. This study highlights a prospective and feasible application of 3D printing in environmental remediation through PMS activation.