Advancing Li-ion storage performance with hybrid vertical carbon/Ni_(3)S_(2)-based electrodes

Conversion-reaction induced charge storage mechanisms of transition metal sulphides have received considerable interest in designing high-capacity electrodes for electrochemical energy storage devices.However,their low conductivity and structural degradation during cycling limit their applications as energy storage devices.A combination of different nickel sulphide phases tailored with carbon nanostructures is suggested to address these limitations.Herein,a facile,two-step approach is demonstrated for fabricating a hybrid electrode,consisting of trinickel disulphide(Ni_(3)S_(2))formed on a metallic Ni nanoparticle supported by vertical carbon nanotubes(VCN)backbone in the form Ni_(3)S_(2)/Ni@VCN.Ni_(3)S_(2)/Ni@VCN electrodes were tested as anode for lithium-ion batteries,and the electrode featured outstanding lithiumstorage capabilities with a high reversible capacity(1113 m Ah g^(-1) after 100 cycles at 100 m A g^(-1)),excellent long-term cycling stability(770 m Ah g^(-1) after 500 cycles at 200 m A g^(-1)),and good rate capability.The resulting electrode performance is one of the best Li-ion storage capabilities in the Ni_(3)S_(2)-type anode materials described.A unique “broccoli-like”structure of polycrystalline Ni_(3)S_(2)capped on conductive VCN backbone helps the interface storage process and boosts lithium storage performance.

N-Graphene Nanowalls via Plasma Nitrogen Incorporation and Substitution: The Experimental Evidence

Incorporating nitrogen(N)atom in graphene is considered a key technique for tuning its electrical properties.However,this is still a great challenge,and it is unclear how to build N-graphene with desired nitrogen configurations.There is a lack of experimental evidence to explain the influence and mechanism of structural defects for nitrogen incorporation into graphene compared to the derived DFT theories.Herein,this gap is bridged through a systematic study of different nitrogen-containing gaseous plasma post-treatments on graphene nanowalls(CNWs)to produce N-CNWs with incorporated and substituted nitrogen.The structural and morphological analyses describe a remarkable difference in the plasma–surface interaction,nitrogen concentration and nitrogen incorporation mechanism in CNWs by using different nitrogen-containing plasma.Electrical conductivity measurements revealed that the conductivity of the N-graphene is strongly influenced by the position and concentration of C–N bonding configurations.These findings open up a new pathway for the synthesis of N-graphene using plasma post-treatment to control the concentration and configuration of incorporated nitrogen for application-specific properties.

Production of Volatile Moth Sex Pheromones in Transgenic Nicotiana benthamiana Plants

Plant-based bioproduction of insect sex pheromones has been proposed as an innovative strategy to increase the sustainability of pest control in agriculture.Here,we describe the engineering of transgenic plants producing(Z)-11-hexadecenol(Z11-16OH)and(Z)-11-hexadecenyl acetate(Z11-16OAc),two main volatile components in many Lepidoptera sex pheromone blends.We assembled multigene DNA constructs encoding the pheromone biosynthetic pathway and stably transformed them into Nicotiana benthamiana plants.The constructs contained the Amyelois transitella AtrΔ11 desaturase gene,the Helicoverpa armigera fatty acyl reductase HarFAR gene,and the Euonymus alatus diacylglycerol acetyltransferase EaDAct gene in different configurations.All the pheromone-producing plants showed dwarf phenotypes,the severity of which correlated with pheromone levels.All but one of the recovered lines produced high levels of Z11-16OH,but very low levels of Z11-16OAc,probably as a result of recurrent truncations at the level of the EaDAct gene.Only one plant line(SxPv1.2)was recovered that harboured an intact pheromone pathway and which produced moderate levels of Z11-16OAc(11.8μg g^(-1) FW)and high levels of Z11-16OH(111.4μg g^(-1)).Z11-16OAc production was accompanied in SxPv1.2 by a partial recovery of the dwarf phenotype.SxPv1.2 was used to estimate the rates of volatile pheromone release,which resulted in 8.48 ng g-1 FW per day for Z11-16OH and 9.44 ng g^(-1 )FW per day for Z11-16OAc.Our results suggest that pheromone release acts as a limiting factor in pheromone biodispenser strategies and establish a roadmap for biotechnological improvements.