*Article* **Structural Characterization, Global and Local Electrochemical Activity of Electroless Ni–P-Multiwalled Carbon Nanotube Composite Coatings on Pipeline Steel**

**Mara Cristina Lopes de Oliveira 1, Olandir Vercino Correa 2, Rejane Maria Pereira da Silva 2, Nelson Batista de Lima 2, Jefferson Thadeu Dias de Oliveira 1, Leandro Antônio de Oliveira 1 and Renato Altobelli Antunes 1,\***


**Abstract:** In this work, composite Ni–P-multiwalled carbon nanotube films were produced by electroless deposition. The main goal was to investigate the influence of multiwalled carbon nanotube loading on the local electrochemical behavior of the composite films, as probed by scanning electrochemical microscopy (SECM). The coatings were also characterized with respect to their crystalline structure, surface, and cross-section morphologies. Adhesion strength was examined by scratch tests. The global electrochemical behavior was evaluated by potentiodynamic polarization. The local electrochemical activity was investigated by probing the Fe2+ oxidation in the surface generation/tip collection mode of the SECM. The results revealed that multiwalled carbon nanotubes increased the adhesion strength and reduced the electrochemical activity on the surface of the coated samples.

**Keywords:** Ni–P/MWCNT composite coatings; electroless deposition; corrosion; scanning electrochemical microscopy
