Raman spectroelectrochemistry is a fundamental technique to characterize single walled carbon nano-tube (SWCNT) films. In this work, we have performed the study of SWCNT films transferred to a glassy carbon electrode using a Langmuir-Schaefer method. Langmuir balance has allowed us to control the characteristics of the film that can be easily transferred to the electrode support. Time-resolved Raman spectroelectrochemistry experiments at scan rates between 20 and 400 mV s(-1) were done in two different solvents, water and acetonitrile. Spectroscopic results indicate that electron transfer of carbon nanotubes is a very fast process. The electrochemical process is reversible in acetonitrile and, on the contrary, nanotubes are degraded when the characterization is performed in water being the degradation independent on the scan rate. (C) 2014 Elsevier Ltd. All rights reserved.