2 research outputs found
Molecular layer deposition of zeolitic imidazolate framework-8 films
Vapor-phase film deposition of metal–organic frameworks
(MOFs) would facilitate the integration of these materials into electronic
devices. We studied the vapor-phase layer-by-layer deposition of zeolitic
imidazolate framework 8 (ZIF-8) by consecutive, self-saturating reactions
of diethyl zinc, water, and 2-methylimidazole on a substrate. Two
approaches were compared: (1) Direct ZIF-8 “molecular layer
deposition” (MLD), which enables a nanometer-resolution thickness
control and employs only self-saturating reactions, resulting in smooth
films that are crystalline as-deposited, and (2) two-step ZIF-8 MLD,
in which crystallization occurs during a postdeposition treatment
with additional linker vapor. The latter approach resulted in a reduced
deposition time and an improved MOF quality, i.e., increased crystallinity
and probe molecule uptake, although the smoothness and thickness control
were partially lost. Both approaches were developed in a modified
atomic layer deposition reactor to ensure cleanroom compatibility
Supporting the improvement of air quality management practices: The “FAIRMODE pilot” activity
This paper presents the first outcomes of the “FAIRMODE pilot” activity, aiming at improving the way in which air quality models are used in the frame of the European “Air Quality Directive”. Member States may use modelling, combined with measurements, to “assess” current levels of air quality and estimate future air quality under different scenarios. In case of current and potential exceedances of the Directive limit values, it is also requested that they “plan” and implement emission reductions measures to avoid future exceedances. In both “assessment” and “planning”, air quality models can and should be used; but to do so, the used modelling chain has to be fit-for-purpose and properly checked and verified. FAIRMODE has developed in the recent years a suite of methodologies and tools to check if emission inventories, model performance, source apportionment techniques and planning activities are fit-for-purpose. Within the “FAIRMODE pilot”, these tools are used and tested by regional/local authorities, with the two-fold objective of improving management practices at regional/local scale, and providing valuable feedback to the FAIRMODE community. Results and lessons learnt from this activity are presented in this paper, as a showcase that can potentially benefit other authorities in charge of air quality assessment and planning