The Influx_Studio (Paris) designed a vision for an urban cleaning machine which could also have social functions. The form was inspired by the Dragon Blood tree and the functions are similar to trees. The air cleaner is driven by energy gained by solar-panels on top of the structure.
The material used should be recycable PET (which is highly available).
It should also offer information about decarbonization. It's emphasized that these structures shouldn't replace regular trees but bring all the positive features of natural trees together!
Description at ArchDaily
For people understanding French there is also a descriptive video on youtube
The office's official homepage is under construction and the projects
are not really described, but on architizer it's said that they have a
"particular attention in sustainable matters".
But I couldn't find if Biomimicry is part of that in their office in general.
Marcus Hubl, excited if these "trees" will be realized! :)