Ultralow charge-discharge voltage gap of 0.05 V in sunlight-responsive neutral aqueous Zn-air battery

Rechargeable neutral aqueous zinc-air batteries(ZABs)are a promising type of energy storage device with longer operating life and less corrosiveness compared with conventional alkaline ZABs.However,the neutral ZABs normally possess poor oxygen evolution reactions(OERs)and oxygen reduction reactions performance,resulting in a large charge–discharge voltage gap and low round-trip efficiency.Herein,we demonstrate a sunlight-assisted strategy for achieving an ultralow voltage gap of 0.05 V in neutral ZABs by using the FeOOH-decorated BiVO4(Fe-BiVO_(4))as an oxygen catalyst.Under sunlight,the electrons move from the valence band(VB)of Fe-BiVO_(4) to the conduction band producing holes in VB to promote the OER process and hence reduce the overpotential.Meanwhile,the photopotential generated by the Fe-BiVO_(4) compensates a part of the charging potential of neutral ZABs.Accordingly,the energy loss of the battery could be compensated via solar energy,leading to a record-low gap of 0.05 V between the charge and discharge voltage with a high round-trip efficiency of 94%.This work offers a simple but efficient pathway for solar-energy utilization in storage devices,further guiding the design of high energy efficiency of neutral aqueous ZABs.

A gene that underwent adaptive evolution, LAC2 (LACCASE), in Populus euphratica improves drought tolerance by improving water transport capacity

Drought severely limits plant development and growth;accordingly,plants have evolved strategies to prevent water loss and adapt to water deficit conditions.However,experimental cases that corroborate these evolutionary processes are limited.The LACCASEs(LACs)family is involved in various plant development and growth processes.Here,we performed an evolutionary analysis of LACs from Populus euphratica and characterized the functions of LACs in Arabidopsis and poplar.The results showed that in PeuLACs,multiple gene duplications led to apparent functional redundancy as the result of various selective pressures.Among them,PeuLAC2 underwent strong positive selection.Heterologous expression analyses showed that the overexpression of PeuLAC2 alters the xylem structure of plants,including thickening the secondary cell wall(SCW)and increasing the fiber cell length and stem tensile strength.Altogether,these changes improve the water transport capacity of plants.The analysis of the physiological experimental results showed that PeuLAC2-OE lines exhibited a stronger antioxidant response and greater drought tolerance than WT.Three genes screened by transcriptome analysis,NAC025,BG1,and UGT,that are associated with SCW synthesis and drought stress were all upregulated in the PeuLAC2-OE lines,implying that the overexpression of PeuLAC2 thickened the SCW,improved the water transport capacity of the plant,and further enhanced its drought tolerance.Our study highlights that genes that have undergone adaptive evolution may participate in the development of adaptive traits in P.euphratica and that PeuLAC2 could be a candidate gene for molecular genetic breeding in trees.