N-doped porous carbon material prepared via direct ink writing for the removal of methylene blue

N-doped porous carbon material has exhibited unique adsorption properties. However, it remains as a challenge to recycle the carbon adsorbent. In this work, a monolithic N-doped carbon material was manufactured via the direct ink writing, a conventional 3D printing technology. Melamine was used as source of nitrogen. It was added to the starch gelatin system to form the ink. The SiO2 microsphere was used as the template agent, which was dispersed in the ink. After the printing, the template was removed by washing with NaOH solution. The size of the SiO2 microsphere determines the pore size of the printed carbon monolithic adsorbent, which shows a high rate of removal of methylene blue, as an illustration. The printed adsorbent can be easily separated from the solution for the recyclable applications. The 3D printing strategy provides us a more convenient method to fabricate structured N-doped porous carbon materials beyond the adsorption of methylene blue.