Carbon Dioxide Catalytic Conversion to Chemicals and Fuels with Non-noble Metal Complexes

Among the major challenges for scientists in the current times, the search for renewable, continuous and portable sources of non-fossil based fuels, combined with the reduction of greenhouse gases such as carbon dioxide, are at the forefront of worldwide attention, both from academic and industrial point of view. Global CO2 emissions reached 35.7 Gt in 2014, translating into an atmospheric CO2 concentration of 408.84 ppm, a 56% increase since the 1990s. The use of hydrogen as energy vector is now considered as a valuable alternative to fossil fuels if produced from renewable sources and combined with low or zero emissions of carbon dioxide. The catalytic reduction of CO2 is a possible answer due to its potential as hydrogen storage method and use of this abundant substrate as C-1 feedstock. An overview of the main developments in homogenously catalysed processes leading to the current state-of-the-art will be here discussed. Another important issue to address is the economical viability of the processes, that are now mainly based on precious metal catalysts. Many research groups worldwide are studying how to replace these catalysts with non-precious counterparts, without affecting the overall process efficiency. Examples of recent contributions, including results from our research group, will be here summarised.