Free-electrodeposited anodic stripping voltammetry sensing of Cu(II) based on Ti3C2Tx MXene/carbon black

A proof-of-principle concept for free-electrodeposited anodic stripping voltammetry (ASV) sensing of Cu 2+ is proposed by using Ti 3 C 2 T x MXene/carbon black (Ti 3 C 2 T x @CB) nanohybrids as electrode materials. Owing to the high adsorption and reduction capability of Ti 3 C 2 T x towards Cu 2+ , Ti 3 C 2 T x MXene enables Cu 2+ to be immobilized and self-reduced directly to form Cu 0 on the Ti 3 C 2 T x @CB electrode surface. As a result an oxidation peak current appears from the re-oxidation of Cu 0 via differential pulse voltammetry. Carbon black (CB) was introduced to prevent Ti 3 C 2 T x Mxene aggregation and improve the related electron transfer as well as enhance their surface area. After optimizing various conditions, a considerable low limit of detection (4.6 nM) and a wide linear range (0.01–15.0 μM) for Cu 2+ were achieved at the working potential from − 0.3 V to 0.0 V (vs SCE). Relative standard deviation (RSD) of eight individual Ti 3 C 2 T x @CB electrodes is 3.72%, and the recoveries from tap water sample and lake water sample were in the ranges of 97.0–108% and 104–107%, respectively. Graphical abstract