Rieche formylation of carbon nanotubes - one-step and versatile functionalization route

We present the direct and one-step Rieche formylation of carbon nanotubes (CNTs) as the most effective (4.00 mmol g(-1)) functionalization route via formylation. Indeed, classical methods, i.e. three-step protocols based on CNT oxidation-reduction-partial oxidation (COOH >> CH2OH >> CHO), were revealed as less effective and more troublesome. All CNT-CHO products were comprehensively analysed by cross-verified potentiometric titration, scanning electron microscopy (SEM), thermogravimetry (TGA), Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy.