Triazine derivatives as metal-free electrocatalysts: do three nitrogen atoms mimic a metal?

Abstract

Environmental changes and climate concerns dictate the necessary transition to sustainable technologies based on green reactions. At the same time, catalysts for carbon dioxide reduction, nitrogen fixation and other electrochemical reactions should be cheap and stable, while exhibiting high selectivity and efficiency. Electrocatalytic reactions make it possible to obtain industrial products under ambient conditions, but this is still difficult and expensive. In the last few years, tremendous progress has been made in the study and application of triazine-based frameworks as catalytic systems and beyond without the use of expensive metals. This short perspective review mainly examines studies not older than five years (more than 75% of citations), with special emphasis being placed on the analysis of the latest research over the last two years (more than 30% of citations). It has been shown that the use of triazines is effective in the reactions of hydrogen evolution (HER), water splitting, oxygen evolution (OER), CO₂ reduction (CO₂RR), ammonia production (NO₃RR and NRR), etc. Based on this analysis, conclusions are drawn about the effectiveness of catalysts and the ways to increase their efficiency. In the near future, we should expect a breakthrough in increasing the hydrophilicity and porosity of triazine catalyst samples, as well as in the use of media in the form of ionic liquids and machine learning and computer modeling of electrode designs.