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Aqueous zinc-ion batteries (AZIBs) are an emerging sustainable and safer technology for large-scale electrical energy storage. Here, we report the synthesis of hybrid materials consisting of V2O5 nanoribbons (NRs) and reduced graphene oxide (rGO) nanosheets as AZIB cathode materials by divalent metal cation-mediated coprecipitation. The divalent metal ions M2+ (Zn2+ and Mn2+) effectively neutralize the negative charges on the surface of microwave-exfoliated crystalline V2O5 NRs and graphene oxide (GO) nanosheets to form a strongly bound assembly. After thermal annealing in a nitrogen atmosphere, GO is converted into rGO with higher electrical conductivity while the layers in V2O5 NRs are expanded by M2+ intercalation. When only Zn2+ ions are used during coprecipitation, the produced Zn-V2O5 NR/rGO hybrid shows a very high reversible specific capacity of ∼395 mAh g–1 at 0.50 A g–1 but suffers from poor stability. This is improved by mixing Mn2+ with Zn2+ ions during coprecipitation. The (Mn + Zn)-V2O5 NR/rGO hybrid shows a slightly lower specific capacity of ∼291 mAh g–1 at 0.5 A g–1 but a substantially improved long-cycling stability and better rate performance due to the stronger binding of Mn atoms in the V2O5 host that serve as stable pillars to support the expanded V2O5 layers.

This study reports the preparation of a set of hybrid materials consisting of Molybdenum disulfide (MoS2) nanopatches on reduced graphene oxide (rGO) nanosheets by applying the microwave specific heating of...

Highly conducting freestanding graphene (FSG) was synthesized by the simple vacuum filtration method and utilized as a cathode current collector for (fluorine doped tin oxide) FTO free quasi‐dye sensitized solar cell (q‐DSSC). Subsequently,conducting polymers (CPs) viz., polyaniline (PANI) and poly(3,4‐ethylene‐di‐oxythiophene) (PEDOT) was decorated on FSG surface by electrochemical polymerization which acts as a electrocatalytst for Pt free q‐DSSC. Entirely, the FSG/CPs affords as a novel cathode architecture for FTO/Pt free electrode for q‐DSSCs. Remarkably, the FSG paper electrode exhibits lower sheet resistance (9‐11 Ω sq‐1) than the FTO which was directly utilized as current collector. Interestingly, the FSG/CPs based cathode shows an improved electro‐catalytic behaviour towards tri‐iodide reduction and in particularly, the photovoltaic performance of FSG/PEDOT shows power conversion efficiency (PCE) of 5.4 % compared with Pt/FTO of 5.1 %. It can be stated that synergetic effect of FSG/PEDOT proves to be a cost effective and efficientsubstitute for cathodes in q‐DSSC.