Precise fabrication of porous one-dimensional gC3N4 nanotubes doped with Pd and Cu atoms for efficient CO oxidation and CO2 reduction

Rational design of graphitic carbon nitride nanostructures (gC(3)N(4)) is vital for various catalytic applications. Herein, we synthesized porous gC(3)N(4) nanotubes (gC(3)N(4)NTs) doped with Pd and Cu (Pd/Cu/gC(3)N(4)NTs) via the consecutive polymerization of melamine in an ethylene glycol solution containing the metal precursors followed by annealing. The gC(3)N(4)NTs, thus produced, possess a well-defined one-dimensional porous nanotube architecture, large surface area (240 m(2) g(-1)), and a homogenous dispersion of Pd and Cu with no need for templates and/or multistep reactions. This merits the CO oxidation activity of Pd/Cu/gC(3)N(4)NTs by 56 degrees C and 96 degrees C higher than that of Pd/gC(3)N(4)NTs and Cu/gC(3)N(4)NTs, respectively. The CO2 reduction activity of Pd/Cu/gC(3)N(4)NTs was a 5.5-fold higher than metal-free gC(3)N(4)NTs. Also, the UV-light irradiation enhanced the CO2 performance of Pd/Cu/gC(3)N(4)NTs by three times. The presented study may pave the way for the utilization of metal-doped gC(3)N(4)NTs in various applications.