Search

Advanced aqueous batteries are promising for next generation flexible devices owing to the high safety, yet still requiring better cycling stability and high capacities in wide temperature range. Herein, a polymeric acid hydrogel electrolyte (PAGE) with 3 M Zn(ClO4)2 was fabricated for high performance Zn/polyaniline (PANI) batteries. With PAGE, even at −35 °C the Zn/Zn symmetrical battery can keep stable for more than 1 500 h under 2 mA cm−2, and the Zn/PANI battery can provide ultra‐high stable specific capacity of 79.6 mAh g−1 for more than 70 000 cycles at 15 A g−1. This can be mainly ascribed to the −SO3−H+ function group in PAGE. It can generate constant protons and guide the (002) plane formation to accelerate the PANI redox reaction kinetics, increase the specific capacity, and suppress the side reaction and dendrites. This proton‐supplying strategy by polymeric acid hydrogel may further propel the development of high performance aqueous batteries. [ABSTRACT FROM AUTHOR]

A 2D zinc(II)-based metal–organic framework (Zn-MOF) formulated as [Zn(bimpy)(1,4-ndc)]·H2O (1, bimpy = 3,5-bis(1-imidazolyl)pyridine and 1,4-ndc = 1,4-naphthalenedicarboxylic acid) was synthesized by solvothermal reaction. Complex 1 exhibits high water and pH-independent stability. It can detect Fe3+ and ascorbic acid (AA) as a "turn-off" fluorescence probe and a "turn-on" fluorescence probe in aqueous solution with high sensitivity and selectivity, respectively. The detection limits of 1 for Fe3+ and AA are about 8.82 × 10−7 M and 6.12 × 10−7 M, respectively. The fluorescence intensity of the Fe3+@1 system can be obviously recovered after adding AA due to the reduction of Fe3+, which exhibits a fluorescence "turn-on" signal (turn-off–on) for Fe3+@1 toward AA with a low detection limit (3.53 × 10−7 M). Complex 1 still exhibits good detection of Fe3+ and AA after washing and using for five cycles. Additionally, two different multi-input molecular logic gates are established. One is used to distinguish the effect of Fe3+ and Fe2+ on the fluorescence of complex 1, and the other is to further explain the regulation of Fe3+ and AA on the fluorescence of complex 1. This work shows that complex 1 is the first MOF-based "turn-on" fluorescent probe for both Fe3+ and AA in aqueous solution. [ABSTRACT FROM AUTHOR]