The review considers the features of the processes of the electrochemical synthesis of nanostructures in ionic liquids (ILs), including the production of carbon nanomaterials, silicon and germanium nanoparticles, metallic nanoparticles, nanomaterials and surface nanostructures based on oxides. In addition, the analysis of works on the synthesis of nanoscale polymer films of conductive polymers prepared using ionic liquids by electrochemical methods is given. The purpose of the review is to dwell upon an aspect of the applicability of ILs that is usually not fully reflected in modern literature, the synthesis of nanostructures (including unique ones that cannot be obtained in other electrolytes). The current underestimation of ILs as an electrochemical medium for the synthesis of nanomaterials may limit our understanding and the scope of their potential application. Another purpose of our review is to expand their possible application and to show the relative simplicity of the experimental part of the work.

Polymer chains endow PILs with unique aggregation structures and morphologies that are inaccessible to monomeric ILs, making them a sustainable material and allowing them to be used in various applications.

Electropolishing of metal surfaces is a benign alternative to mechanical treatment. Ionic liquids are considered as green electrolytes for the electropolishing of metals. They demonstrate a number of advantages in comparison with acid aqueous solutions and other methods of producing smooth or mirror-like surfaces that are required by diverse applications (medical instruments, special equipment, implants and prostheses, etc.). A wide window of electrochemical stability, recyclability, stability and tunability are just a few benefits provided by ionic liquids in the title application. An overview of the literature data on electropolishing of such metals as Ti, Ni, Pt, Cu, Al, U, Sn, Ag, Nb, stainless steel and other alloys in ionic liquids is presented.

For the first time, the anodic behavior of platinum and titanium in ionic liquids (ILs) based on the imidazolium cation was investigated. ILs were established to possess a set of advantages compared with the traditional sulfuric acid electrolytes. It isn't necessary to maintain both a particular temperature and to use environmentally-harmful reagents, such as methanol or hydrofluoric acid, when electropolishing metals in IL media. The addition of propylene glycol to BMImCl (1 : 1) results in the formation of layers of titanium dioxide nanotubes on the metal surface.

The green and sustainable electrocatalytic conversion of nitrogen-containing compounds to ammonia is currently in high demand in order to replace the eco-unfriendly Haber–Bosch process. Model catalysts for the nitrate reduction reaction were obtained by electrodeposition of metal Co, Fe, and bimetallic Fe/Co nanoparticles from aqueous solutions onto a graphite substrate. The samples were characterized by the following methods: SEM, XRD, XPS, UV–vis spectroscopy, cyclic (and linear) voltammetry, chronoamperometry, and electrochemical impedance spectroscopy. In addition, the determination of the electrochemically active surface was also performed for all electrocatalysts. The best electrocatalyst was a sample containing Fe-nanoparticles on the layer of Co-nanoparticles, which showed a Faradaic efficiency of 58.2% (E = −0.785 V vs. RHE) at an ammonia yield rate of 14.6 μmol h⁻¹ cm⁻² (at ambient condition). An opinion was expressed to elucidate the mechanism of coordinated electrocatalytic action of a bimetallic electrocatalyst. This work can serve primarily as a starting point for future investigations on electrocatalytic conversion reactions to ammonia using model catalysts of the proposed type.