3D‐printed green and low‐cost porous g‐C3N4/geopolymer components for the removal of methylene blue from wastewater

Abstract In this study, we report that geopolymer materials containing different amounts of graphitic carbon nitride (g‐C 3 N 4 ) (C 3 N 4 /GP) can remove methylene blue (MB) using the synergistic effects of adsorption and photodegradation. A geopolymer containing 3 wt% g‐C 3 N 4 (3 wt%C 3 N 4 /GP) had the best MB removal efficiency of 94.62% within 60 min, under visible light. The results showed that geopolymers can act as carriers for g‐C 3 N 4 , and the relative amount of adsorbent and photocatalyst influences the removal of MB. 3 wt%C 3 N 4 /GP was also used for additive manufacturing by using direct ink writing technology. In order to improve the efficiency of MB removal, a pore‐forming agent (K12) was added in the synthesis process to prepare three‐dimensional‐printed porous C 3 N 4 /GP. The results showed that the porous C 3 N 4 /GP was effective in removing MB. This work provides a simple strategy for preparing efficient and green materials for removing organic pollutants.