Towards electrochemical hydrogen storage in liquid organic hydrogen carriers via proton-coupled electron transfers

Green hydrogen is identified as one of the prime clean energy carriers due to its high energy density and a zero emission of CO_(2).A possible solution for the transport of H_(2)in a safe and low-cost way is in the form of liquid organic hydrogen carriers(LOHCs).As an alternative to loading LOHC with H_(2)via a two-step procedure involving preliminary electrolytic production of H_(2)and subsequent chemical hydrogenation of the LOHC,we explore here the possibility of electrochemical hydrogen storage(EHS)via conversion of proton of a proton donor into a hydrogen atom involved in covalent bonds with the LOHC(R)via a protoncoupled electron transfer(PCET)reaction:2nH^(+)+2ne^(-)+Rox■n H_(2)^(0)Rred.We chose 9-fluorenone/fluorenol(Fnone/Fnol)conversion as such a model PCET reaction.The electrochemical activation of Fnone via two sequential electron transfers was monitored with in-situ and operando spectroscopies in absence and in presence of different alcohols as proton donors of different reactivity,which enabled us to both quantify and get the mechanistic insight on PCET.The possibility of hydrogen extraction from the loaded carrier molecule was illustrated by chemical activation.

Seamless integration of bioelectronic interface in an animal model via in vivo polymerization of conjugated oligomers

Leveraging the biocatalytic machinery of living organisms for fabricating functional bioelectronic interfaces,in vivo,defines a new class of micro-biohybrids enabling the seamless integration of technology with living biological systems.Previously,we have demonstrated the in vivo polymerization of conjugated oligomers forming conductors within the structures of plants.Here,we expand this concept by reporting that Hydra,an invertebrate animal,polymerizes the conjugated oligomer ETE-S both within cells that expresses peroxidase activity and within the adhesive material that is secreted to promote underwater surface adhesion.The resulting conjugated polymer forms electronically conducting and electrochemically activeμm-sized domains,which are inter-connected resulting in percolative conduction pathways extending beyond 100μm,that are fully integrated within the Hydra tissue and the secreted mucus.Furthermore,the introduction and in vivo polymerization of ETE-S can be used as a biochemical marker to follow the dynamics of Hydra budding(reproduction)and regeneration.This work paves the way for well-defined self-organized electronics in animal tissue to modulate biological functions and in vivo biofabrication of hybrid functional materials and devices.