A facile and rapid method to synthesize graphene/layered double hydroxide(LDH)nanohybrids by a microwave technique is demonstrated.The synthesis procedure involves hydrothermal crystallization of Zn–Al LDH at the sam...A facile and rapid method to synthesize graphene/layered double hydroxide(LDH)nanohybrids by a microwave technique is demonstrated.The synthesis procedure involves hydrothermal crystallization of Zn–Al LDH at the same time in situ reduction of graphene oxide(GO)to graphene.The microstructure,composition,and morphology of the resulting graphene/LDH nanohybrids were characterized.The results confirmed the formation of nanohybrids and the reduction of graphene oxide.The growth mechanism of LDH and in situ reduction of GO were discussed.The LDH sheet growth was found to prevent the scrolling of graphene layers in resulting hybrids.The electrochemical properties exhibit superior performance for graphene/Zn–Al LDH hybrids over pristine graphene.The present approach may open a strategy in hybridizing graphene with multimetallic nano-oxides and hydroxides using microwave method.展开更多
In this study,tannic acid(TA)was investigated as flame retardant agent for PLA.Different strategies to modify its thermal degradation pathway have been explored in order to improve its charring effect.The first one co...In this study,tannic acid(TA)was investigated as flame retardant agent for PLA.Different strategies to modify its thermal degradation pathway have been explored in order to improve its charring effect.The first one consists in combining TA with organomodified montmorillonite(oMMT),and enables limiting the thermo-oxidative degradation of TA and promoting the formation of an effective char layer.Flame-retardant(FR)behavior of PLA-based composition has been found to be positively impacted by this combination since a reduction of the peak of Heat Release Rate(PHRR),more important than the value recorded when oMMT and tannic acid are used separately,has been obtained.The second strategy,in which tannic acid was associated with a biosourced phosphorousbased compounds,i.e.metallic phytate salt,evidenced another alternative allowing enhancing TA flame retardant effect at 30 wt%loading content.The third and last strategy explored aims to chemically modify TA via a chemical grafting of phosphoric acid groups.This phosphorylated TA was shown to present the most effective flame-retardant(FR)effect.However,an important reduction of PLA molecular weight was observed.展开更多
The reality of plastic pollution is no longer under debate:It has invaded our daily lives and is present all around us,with our oceans being no exception.In fact,a seventh“continent”has appeared in the oceans,compos...The reality of plastic pollution is no longer under debate:It has invaded our daily lives and is present all around us,with our oceans being no exception.In fact,a seventh“continent”has appeared in the oceans,composed of plastics and microplastics!Newspapers including Le Monde in France and The Guardian in United Kingdom recently headlined the record rate of microplastic accumulation in the Arctic Ocean.These headlines referred to an article published in Nature Communications[1]that reported the finding of up to 12000 plastic microparticles per liter of water frozen in the sea ice.Given this finding,what future solutions can counteract this particularly insidious pollution?展开更多
基金‘‘Région Wallonne’’and European Community(FEDER+1 种基金FSE)and F.R.S.-FNRS(Belgium)for financial supportfunded by the Interuniversity Attraction Poles Programme(P7/05)initiated by the Belgian Science Policy Office
文摘A facile and rapid method to synthesize graphene/layered double hydroxide(LDH)nanohybrids by a microwave technique is demonstrated.The synthesis procedure involves hydrothermal crystallization of Zn–Al LDH at the same time in situ reduction of graphene oxide(GO)to graphene.The microstructure,composition,and morphology of the resulting graphene/LDH nanohybrids were characterized.The results confirmed the formation of nanohybrids and the reduction of graphene oxide.The growth mechanism of LDH and in situ reduction of GO were discussed.The LDH sheet growth was found to prevent the scrolling of graphene layers in resulting hybrids.The electrochemical properties exhibit superior performance for graphene/Zn–Al LDH hybrids over pristine graphene.The present approach may open a strategy in hybridizing graphene with multimetallic nano-oxides and hydroxides using microwave method.
文摘In this study,tannic acid(TA)was investigated as flame retardant agent for PLA.Different strategies to modify its thermal degradation pathway have been explored in order to improve its charring effect.The first one consists in combining TA with organomodified montmorillonite(oMMT),and enables limiting the thermo-oxidative degradation of TA and promoting the formation of an effective char layer.Flame-retardant(FR)behavior of PLA-based composition has been found to be positively impacted by this combination since a reduction of the peak of Heat Release Rate(PHRR),more important than the value recorded when oMMT and tannic acid are used separately,has been obtained.The second strategy,in which tannic acid was associated with a biosourced phosphorousbased compounds,i.e.metallic phytate salt,evidenced another alternative allowing enhancing TA flame retardant effect at 30 wt%loading content.The third and last strategy explored aims to chemically modify TA via a chemical grafting of phosphoric acid groups.This phosphorylated TA was shown to present the most effective flame-retardant(FR)effect.However,an important reduction of PLA molecular weight was observed.
文摘The reality of plastic pollution is no longer under debate:It has invaded our daily lives and is present all around us,with our oceans being no exception.In fact,a seventh“continent”has appeared in the oceans,composed of plastics and microplastics!Newspapers including Le Monde in France and The Guardian in United Kingdom recently headlined the record rate of microplastic accumulation in the Arctic Ocean.These headlines referred to an article published in Nature Communications[1]that reported the finding of up to 12000 plastic microparticles per liter of water frozen in the sea ice.Given this finding,what future solutions can counteract this particularly insidious pollution?
