Electrochemical energy conversion technologies are regarded as an excellent pathways to achieve clean, efficient and sustainable energy production. Unfortunately, besides the latest advanced in nanotechnology, expensive noble metal alloys are still the preferred catalyst for reactions such as hydrogen evolution, or oxygen reduction, among others. However, in recent years, the production of disordered materials have opened an alternative approach to design electrocatalysts, where the presence of defects significantly modify the interaction with their surroundings transforming inactive materials into efficient electrocatalyst. Disordered and non-stoichiometric nanomaterials exhibit complex elemental composition and defective crystal structure, these issues difficult their design making necessary the use of computational tools to understand and properly engineer the electrocatalyst. The purpose of this project is to investigate the electronic and catalytic properties of disordered and non-stoichiometric nanomaterials by means of density functional theory.