Numerous challenges in Europe are intimately related to the exploitation of foreign, currently non-renewable, and polluting energy resources. A well-known example lies in the use of petrol and methane as fuels in engines and heating systems. Europe is largely dependent on foreign countries in the import of these goods, yet its industrial and societal fabric is highly reliant on their immediate and reasonably-priced availability for consumption. Further, their combustion releases CO2 in the atmosphere, which plays a determining and detrimental role in the context of global warming and climate change. These criticalities have a negative impact at the environmental and socio-economic level, and underlie a number of geo-political dependences. In turn, enabling the cost-efficient upgrade of CO2 into fuels and other value-added chemicals would drive a positive change for the environment and for our society.
Notwithstanding several breakthroughs, the process to convert CO2 into fuels does not yet meet the techno-economic figures of merit that determine the viable commercialisation of CO2 recycling devices. The overarching goal of NANOCO2RE consisted in providing novel theoretical elements to identify better catalysts for CO2 upgrade. More in particular, the focus of the Action was centered towards the optimization of the performance of a class of system, which is a prominent candidate in enabling cost-efficient CO2 upgrade: Cu-based heterogeneous catalysts.
The figures of merit that describe the performance of heterogeneous catalysts are their activity, selectivity, and stability. The activity of a catalyst refers to the amount of reagent it transforms within a fixed unit of time. The selectivity of a catalyst describes its ability in converting the reagent into a single product, rather than a multiplicity. The stability of a catalyst labels its propensity in not diminishing its activity and/or selectivity when in operation, over a fixed period of time.
The catalytic activity, selectivity, and stability of a heterogeneous catalyst can be engineered by modifying a number of intrinsic and extrinsic variables. The catalyst size, composition, and shape belong to the former family. The chemistry of the support, solvent, and ligands interacting with the catalyst belong to the latter. The rational design of heterogeneous catalysts, in turn, hinges on the understanding of how to optimize the effects determined by this high-dimensional number of variables.
