Expression of concern: In situ growth of N-doped carbon nanotubes from the products of graphitic carbon nitride etching by nickel nanoparticles

Expression of concern for 'In situ growth of N-doped carbon nanotubes from the products of graphitic carbon nitride etching by nickel nanoparticles' by Mariusz Pietrowski et al., Nanoscale Adv., 2024, 6, 1720-1726, https://doi.org/10.1039/D3NA00983A.