RESUMEN
3D graphene-based materials offer immense potentials to overcome the challenges related to the functionality, performance, cost, and stability of fuel cell electrocatalysts. Herein, a nitrogen (N) and sulfur (S) dual-doped 3D porous graphene catalyst is synthesized via a single-row pyrolysis using biomass as solitary source for both N and S, and structure directing agent. The thermochemical reaction of biomass functional groups with graphene oxide facilitates in situ generation of reactive N and S species, stimulating the graphene layers to reorganize into a trimodal 3D porous assembly. The resultant catalyst exhibits high ORR and OER performance superior to similar materials obtained through toxic chemicals and multistep routes. Its stability and tolerance to CO and methanol oxidation molecules are far superior to commercial Pt/C. The dynamics governing the structural transformation and the enhanced catalytic activity in both alkaline and acidic media are discussed. This work offers a unique approach for rapid synthesis of a dual-heteroatom doped 3D porous-graphene-architecture for wider applications.
RESUMEN
Recently, layered transition-metal dichalcogenides (TMDs) have gained great attention for their analogous graphite structure and high theoretical capacity. However, it has suffered from rapid capacity fading. Herein, we present the crumpled reduced graphene oxide (RGO) decorated MoS2 nanoflowers on carbon fiber cloth. The three-dimensional framework of interconnected crumpled RGO and carbon fibers provides good electronic conductivity and facile strain release during electrochemical reaction, which is in favor of the cycling stability of MoS2. The crumpled RGO decorated MoS2 nanoflowers anode exhibits high specific capacity (1225 mAh/g) and excellent cycling performance (680 mAh/g after 250 cycles). Our results demonstrate that the three-dimensional crumpled RGO/MoS2 nanoflowers anode is one of the attractive anodes for lithium-ion batteries.
