Development of an innovative combination of microanalytical techniques dedicated to unravelling internal structure of fine aerosol particles

Doctorant: Damian Siepka

Download the poster presenting the thesis project

   Heavily industrialized areas suffer from smog pollution that is often related to coal burning and also to the traffic. The most well-known example of smog is the London pea–souper smog, which occurred intermittently until the 50’s, when coal burning became forbidden. Besides visibility degradation, the London smog episodes caused serious health effects and excess deaths. A significant number of health problems related to atmospheric aerosols and fog droplets are believed to be more due to particles with diameters less than 10 μm, because these particles can penetrate deeply into the respiratory system. Much of the pollution-related adverse health effects may be closely related to the presence of ultrafine airborne particles. Recently, the role of PM1 and ultrafine particles in health related issues has been discussed. The importance of complex particulate matter analysis appears to be justified if we additionally consider a reduction in the productivity of the exposed urban and sub-urban ecosystems. The approved and well-received method of determination of chemical composition is bulk analysis of filter-collected particles. The main advantages of this type of analysis are: identification of the main components (chemical elements, compounds or ions), fast and validated analysis, facility in the statistical data treatment etc. On the other hand, there is still a lack of information about surface and internal structure composition of individual particles in all aerosol types. Only a few works were dedicated to the analysis of single particles by microanalytical techniques (microscopy and micro-spectroscopy) for ambient aerosols. On the other hand, there has been comprehensive parameterization carried out for urban airborne particles. The great potential of current techniques is set in a possibility to collect complex data about the chemical composition of the particles from a large range of fractions (discriminated by an aerodynamic diameter), both on the surface and in the core. Data on the composition may be further supplemented by morphological parameterization about shape and diameter (area–based particle size). Additionally, micro-spectroscopic techniques can be coupled into an analytical system, whereby each of them can provide different types of information for an individual particle in the sample using a non-destructive method of analysis.

   The main objective of current research is to apply combination of four microanalytical techniques: SEM/EDX, Raman microspectroscopy (RMS), ToF-SIMS and FTIR microspectroscopy to provide insight information about size, morphological features and chemical composition of urban aerosol particles from PM10, PM2.5 and PM1 fractions. The collected data will be supplemented by the complex parameterization of the particles by Scanning Electron Microscopy (SEM). In all steps of the designed analytical protocol, a procedure called Single Particle Analysis (SPA) will be used for statistically relevant number of particles in the sample. A fundamental part of this procedure is an application of Multivariate Statistical Methods. The final step of this project would be the formulation of analytical algorithm for fully automated procedure both in the analysis and statistical processing of objects in micro-scale, adopted in the analysis of urban aerosol particles collected in heavily urbanized areas.

  The scientific reliability for the procedure set forth in this project is participating the two academic institutions: LASIR CNRS (FR) and ICBN KUL (PL).  The scientific tutor in Poland is prof. Elżbieta Anna Stefaniak the director of Centre for Interdisciplinary Research of John Paul II Catholic University of Lublin. The scientific tutor in France is Dr. Sophie Sobanska, charge de recherche CNRS, habilitée à diriger des recherches (HDR).

Director in Poland: prof. Elżbieta Anna Stefaniak (supervisor)

Director in France: Dr. Sophie Sobanska, charge de recherche CNRS (co-supervisor)

Laboratories
joint thesis Université Lille 1 - Nicolaus Copernicus University in Torun

Center for Interdisciplinary Research of John Paul II Catholic University of Lublin (Poland) KUL / LASIR
 

Financing
BGF scholarship programme/LASIR