Boron-doped high-entropy oxide toward high-rate and long-cycle layered cathodes for wide-temperature sodium-ion batteries

03-type layered metal oxides hold great promise for sodium-ion batteries cathodes owing to their energy density advantage.However,the severe irreversible phase transition and sluggish Na^(+)diffusion kinetics pose significant challenges to achieve high-performance layered cathodes.Herein,a boron-doped03-type high entropy oxide Na(Fe_(0.2)Co_(0.15)Cu_(0.05)Ni_(0.2)Mn_(0.2)Ti_(0.2))B_(0.02)O_(2)(NFCCNMT-B_(0.02))is designed and the covalent B-O bonds with high entropy configuration ensure a robust layered structure.The obtained cathode NFCCNMT-B_(0.02)exhibits impressive cycling performance(capacity retention of 95%and 82%after100 cycles and 300 cycles at 1 and 10 C,respectively)and outstanding rate capability(capacity of 83 mAh g^(-1)at 10 C).Furthermore,the NFCCNMT-B_(0.02)demonstrates a superior wide-temperature performance,maintaining the same capacity level(113,4 mAh g^(-1)@-20℃,121 mAh g^(-1)@25℃,and 119 mAh g^(-1)@60℃)and superior cycle stability(90%capacity retention after 100 cycles at 1 C at-20℃).The high-entropy configuration design with boron doping strategy contributes to the excellent sodium-ion storage performance.The high-entropy configuration design effectively suppresses irreversible phase transitions accompanied by small volume changes(ΔV=0.65 A3).B ions doping expands the Na layer distance and enlarges the P3 phase region,thereby enhancing Na^(+)diffusion kinetics.This work offers valuable insights into design of high-performance layered cathodes for sodium-ion batteries operating across a wide temperature.

Prognosis and outcome of intrauterine treatment of fetuses with critical congenital heart disease

Background:Intrauterine valvuloplasty is an innovative therapy,which promotes ventricular growth and function in some congenital heart diseases(CHDs).The technique remains challenging and can only be performed in a few centers.This study aimed to assess the feasibility and mid-term outcomes of fetal cardiac intervention(FCI)in fetuses with critical CHD in an experienced tertiary center.Methods:Five fetal aortic valvuloplasty(FAV)or fetal pulmonary valvuloplasty(FPV)procedures were performed in our fetal heart center between August 2018 and May 2022.Technical success was defined as crossing the aortic or pulmonary valve and balloon inflation,followed by evidence of increased blood flow across the valve and/or new regurgitation.Follow-up clinical records and echocardiography were obtained during the prenatal and postnatal periods.Results:Five fetuses received FAV or FPV,including critical aortic stenosis(n=2)and pulmonary atresia with intact ventricular septum(n=3).The mean maternal age was 33.0±2.6 years.The median gestational age(GA)at diagnosis was 24 weeks(range,22-26 weeks).The median GA at intervention was 29 weeks(range,28-32 weeks).All five cases underwent successful or partially successful procedures.One patient had pulmonary valve perforation without balloon dilation.No procedure-related deaths or significant complications occurred.However,one neonatal death occurred due to heart and renal failure.The median follow-up period was 29.5 months(range,8.0-48.0 months).The four surviving patients had achieved biventricular circulation,exhibited improved valve,and ventricular development at the last follow-up visit.Conclusion:Intrauterine FCI could be performed safely with good prognosis in critical CHD.

A Note on the Maximal Functions on Weighted Harmonic AN Groups

In this paper, the authors point out that the methods used by Li(2004, 2005,2007) can be applied to study maximal functions on weighted harmonic AN groups.