We exploit the unique properties of the nanoporous materials integrated in 2D photonic systems such as diffraction gratings toward spectroscopic-like, smart-phone assisted detection of VOCs.

MOF-based diffraction gratings sensors for styrene

These photonic MOF-heterostructures can be used as very low-cost sensing platforms compatible with smart-phone technology.

Selectivity by sorption kinetics

We demonstrate that the detection mode can be dynamic! Depending on the adsorption/desorption rates, dynamic selectivity towards vapors can be obtained.

O. Dalstein et al, Adv. Funct. Mater. 2016

Making photonic sensors out of cracks!

Formation of cracks in colloidal films is generally considered as major drawback for the fabrication of photonic devices. However, in controlled conditions the controlled drying of colloidal droplets results in the formation of parallel periodic cracks oriented by the evaporation front-line as observed in mud’s cracks.
In this contribution, we demonstrate for the first time that colloidal photonic devices can be fabricated by engineering cracks. In particular Metal-Organic Framework colloidal films (sub-50 nm MIL 101 or ZIF-8) can be crack-patterned during dip-coating deposition where the crack propagation is oriented by the evaporation front.

Have a look to the crack self-assembly mechanism here!

This versatile method allows preparation of periodic crack arrays with tunable periodicity, on large surface and on substrates having various chemical nature and geometry (including the inner surface of a tube) not achievable with other lithographic techniques.We show that arrays of periodic cracks diffract lights and can be used as photonic platform. We also propose a new concept of “on-demand” optical sensors, based on MOF diffraction gratings, with outstanding sensitivity, easily adjustable as function of the desired detection range.

O. Dalstein et al, Angew. Chem. 2017