Advances in tailoring the water content in porous carbon aerogels using RT-pulsed fluorination

Fluorination and its Effects on Electrocatalysts for Low‐Temperature Fuel Cells

“…Moreover, the thermal and chemical stabilities were enhanced without drastic structural changes and a decrease in electrical conductivity. [ 28 ]…”

“…Moreover, the thermal and chemical stabilities were enhanced without drastic structural changes and a decrease in electrical conductivity. [28] Moreover, this route allows the monitoring in real-time of the grafting thanks to the balance of the controlled injections of F 2 and the changes in the F 2 pressure inside the reactor. Grafting results in a decrease of the fluorine pressure whereas its increase evidences an over-fluorination.…”

“…Figure 1.Relative pressure (mbar) and pure molecular fluorine injections (mL min −1 ) managed at room temperature owing to pulsed fluorination method. Reproduced with permission [28]. Copyright 2022, Elsevier.…”

A review about the fluorination and oxyfluorination of carbon fibres

“…When the specific surface area is increased, through a nanostructuration (e.g. nanofibres [33] or multiwalled carbon nanotubes, MWCNTs [34]), or porosity [35], the reactivity increases as well the risk of decomposition under F2 atmosphere. It is important to note the risk of exfoliation when the reactive gas is introduced at high temperature with high reactive gas flux.…”

“…RT-pulsed fluorination has been developed for materials that cannot be fluorinated using direct fluorination (e.g. carbon aerogels, CA), due to their high specific surface areas or high sp 3 hybridised carbon amounts, with the objective to create a fluorination method less expensive than controlled fluorination [35]. It is similar to static fluorination, although the pre-calculated amount of fluorine is not introduced at once, but in several small injections, allowing to observe the fluorine absorption and reaction kinetics, divided into 4 steps according to the authors: after vacuum and fluorine first injection (step 1), fluorine rapidly reacts with CA, leading to a purification of the carbon lattice and fluorine grafting on the surface vacant sites of the carbon (step 2).…”