Heteroatom-Doped Carbon Nanotube Membranes from Waste Biomass for Photoelectro-Catalytic Water Purification

Printing and dyeing wastewater, that is discharged after textile printing and dyeing processing, can cause irreversible damage to the aquatic ecosystem and harm the health of human beings. Till now, completely and readily removing dye molecules from industrial wastewater using a single catalyst rather than the combination of several materials remains a significant challenge. Herein, in situ preparation of carbon nanotube membranes (N-CNTM and N-TiO2-CNTM) are reported that are doped using N with/without TiO2, respectively. These membranes can simultaneously function as an adsorber, a photo-catalyst, and an electrocatalyst to efficiently remove dye pollutes from industrial waste water. Further researches reveal that the formation of p-n type heterojunction inside of the N-CNTM and N-TiO2-CNTM, can improve the hole separation and charge storage abilities, resulting in the efficient removal of dyes in the industrial waste water. This work provides a promising approach for the preparation of functionalized carbon nanotubes derived from waste biomass for the treatment of industrial water, reflecting the concept of treating waste with waste. Using biomass tannic acid as the carbon source, N-TiO2-doped carbon nanotube membrane (N-TiO2-CNTM) are continuously prepared in situ. This membrane can simultaneously act as an adsorbent, photocatalyst, and electrocatalyst, effectively removing dye pollutants from industrial wastewater. image