Insights on soot nanoparticle formation using advanced characterisation tools

The London and Paris city authorities' announcements aiming at a ban of diesel and gasoline light duty engines from their cities altogether gave raise to misinformation that is being presented in the popular press. The demise of the internal combustion engine (ICE) has been, however, greatly exaggerated as hybrids are a key part of the long term transport plan; mild hybrids with clean gasoline ICE are foreseen to be popular in small and medium sized cars, while heavy duty long haul will still be reliant on diesel, so will heavier commuter cars. Emissions regulations will over time be tightened within their allowable thresholds and extended to cover new pollutants. More specifically particulate emissions are likely to be altered to completely new number and size-based metrics with the likelihood of particle size threshold being as low as sub-ten nanometres. To date there are only limited studies available on GDI soot. In particular, the formation of soot under real-driving conditions has been scarcely covered. The complex morphology of soot nanoparticles plays an important role in determining their exact behaviour, and thus the myriad problems that they cause. This includes their effect on human health when inhaled, contribution to the greenhouse effect via absorption of visible light, degradation of marine habitats, and damage to the lubricating properties of engine oil formulations. Morphological characterisation is an important initial step in developing intelligent strategies to combat the problems caused by soot emissions.