Cooperative structure of Li/Ni mixing and stacking faults for achieving high-capacity Co-free Li-rich oxides

Co-free Li-rich layered oxides(LLOs)are emerging as promising cathode materials for Li-ion batteries due to their low cost and high capacity.However,they commonly face severe structural instability and poor electrochemical activity,leading to diminished capacity and voltage performance.Herein,we introduce a Co-free LLO,Li_(1.167)Ni_(0.222)Mn_(0.611)O_(2)(Cf-L1),which features a cooperative structure of Li/Ni mixing and stacking faults.This structure regulates the crystal and electronic structures,resulting in a higher discharge capacity of 300.6 mA h g^(-1)and enhanced rate capability compared to the typical Co-free LLO,Li_(1.2)Ni_(0.2)Mn_(0.6)O_(2)(Cf-Ls).Density functional theory(DFT)indicates that Li/Ni mixing in LLOs leads to increased Li-O-Li configurations and higher anionic redox activities,while stacking faults further optimize the electronic interactions of transition metal(TM)3d and non-bonding O 2p orbitals.Moreover,stacking faults accommodate lattice strain,improving electrochemical reversibility during charge/discharge cycles,as demonstrated by the in situ XRD of Cf-L1 showing less lattice evolution than Cf-Ls.This study offers a structured approach to developing Co-free LLOs with enhanced capacity,voltage,rate capability,and cyclability,significantly impacting the advancement of the next-generation Li-ion batteries.

Synergy of porous structure and cation doping in Ta3N5 photoanode towards improved photoelectrochemical water oxidation

Herein,a cross-linked porous Ta3N5 film was prepared via a simple solution combustion route followed by a high-temperature nitridation process for photoelectrochemical(PEC) water oxidation.Meanwhile,the metal cations(Mg2+ and Zr4+) were incorporated into the porous Ta3N5 to enhance the PEC performance.The porous Mg/Zr co-doped Ta3N5 photoanode yielded a photocurrent density of 1.40 mA cm^(-2) at 1.23 V vs RHE,which is 5.6 times higher than that of the dense Ta3N5 photoanode.The enhanced performance should be ascribed to the synergistic effect of porous structure and cation doping,which can enlarge the electrochemical active surface area and accelerate the charge transfer by introducing ON substitution defects.Subsequently,Co(OH)2 cocatalyst was loaded on the Mg/Zr-Ta3N5 photoanode to negatively shift the onset potential to 0.45 V vs RHE and further improve the photocurrent density to 3.5 mA cm^(-2)at 1.23 V vs.RHE,with a maximum half-cell solar to hydrogen efficiency of 0.45%.The present study provides a new strategy to design efficient Ta3N5 photoelectrodes via the simultaneous control of the morphology and composition.

Applications of CRISPR/Cas genome editing in economically important fruit crops:recent advances and future directions

Fruit crops,consist of climacteric and non-climacteric fruits,are the major sources of nutrients and fiber for human diet.Since 2013,CRISPR/Cas(Clustered Regularly Interspersed Short Palindromic Repeats and CRISPR-Associated Protein)genome editing system has been widely employed in different plants,leading to unprecedented progress in the genetic improvement of many agronomically important fruit crops.Here,we summarize latest advancements in CRISPR/Cas genome editing of fruit crops,including efforts to decipher the mechanisms behind plant development and plant immunity,We also highlight the potential challenges and improvements in the application of genome editing tools to fruit crops,including optimizing the expression of CRISPR/Cas cassette,improving the delivery efficiency of CRISPR/Cas reagents,increasing the specificity of genome editing,and optimizing the transformation and regeneration system.In addition,we propose the perspectives on the application of genome editing in crop breeding especially in fruit crops and highlight the potential challenges.It is worth noting that efforts to manipulate fruit crops with genome editing systems are urgently needed for fruit crops breeding and demonstration.

Accelerating electron transport in Eosin Y by bidentately bridging on BaSnO_(3)for noble-metal-free photocatalytic H 2 production

The separation and transport of photogenerated carriers is regarded as a curial factor in photocatalytic H_(2)pro-duction.As known in solar cells and photoelectron-chemistry,to strengthen the electron conduction for effective utilization of carriers,the electron transport material(ETM)is widely applied.Herein,inspired by the function of ETM,we adopted barium stannate(BaSnO_(3),labeled as BSO)as an excellent ETM which had the merits of high electron mobility,suitable conduction band position and simple preparation,to adjust the carrier kinetics of dye Eosin Y(EY)-sensitized photocatalytic system.Detailly,the photocatalytic system with the spatial sepa-ration sites of photogenerated carriers excitation and water reduction reaction was elaborately constructed,that was,dye EY-sensitized BSO(EY/BSO)for photocatalytic H_(2)production.The photocatalytic H_(2)-production rate of EY/BSO(257𝜇mol·h^(−1)·g EY^(−1))in the absence of noble metals was 28.6 times higher than that of single EY(∼9𝜇mol·h^(−1)·g EY^(−1))under visible-light irradiation.With systematic and comprehensive characterizations,the formed electron transport channel by the bidentate bridging of EY on BSO could accelerate the transfer of photogenerated electrons from EY to BSO,promoting the effective separation of photogenerated carriers for the enhanced pho-tocatalytic performance.Moreover,the water reduction reaction for H_(2)production proceeded on the surface of BSO that acted as the H_(2)-evolution cocatalyst,avoiding the use of high-cost noble metals.Furthermore,based on the well-proved ETM-based concept in the EY/BSO system,La-doped BaSnO_(3)(LBSO)with better electron trans-port ability was adopted to construct EY/LBSO system(344𝜇mol·h^(−1)·g EY^(−1))which showed better photocatalytic activity than EY/BSO.