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In this study, quaternized poly (arylene ether sulfone) (QNPAES) was synthesized using conventional nucleophilic aromatic polycondensation. We then developed a blended membrane composed of sulfonated poly (ether ether ketone) (SPEEK) using facile solution casting. A series of mixed hybrid membranes of SPEEK/QNPAES were prepared by varying the wt% of QNPAES mixed with SPEEK. The results showed that an appropriate amount of QNPAES (i.e., 6 wt%) could significantly improve the mechanical strength, proton conductivity and physicochemical properties of a prepared mixed membrane, as well as the proton exchange membrane fuel cell (PEMFC) performance and durability at relative humidity (RH) of 20%. Specifically, a SPEEK/QNPAES at 6 wt% provides a current output, power output and endurance of 0.431 A cm−2, 0.15 W cm−2 and over 900 h, respectively, at an RH of 20% and 60 °C. These results can be attributed to acid-base ionic crosslinking, which offers effective interfacial compatibility between SPEEK and QNPAES. A PEMFC with SPEEK/QNPAES membranes when used at 20% RH achieved significantly advanced performance and ultra-high, long-term durability compared with those of PEMFCs with bare SPEEK, suggesting that SPEEK/QNPAES membranes can be used as polymer electrolyte membranes. Proton transport of SPEEK/QNPAES acid-base blended membranes for PEFC performance and ultra-high, long-term durability over 900 h. [Display omitted] • QNPAES was synthesized using conventional nucleophilic aromatic polycondensation. • The SPEEK/QNPAES (6 wt%) demonstrated significantly improved proton conductivity. • Acid-base crosslinking offers effective compatibility between SPEEK/QNPAES. • The SPEEK/QNPAES provides maximum current output and power density. • The SPEEK/QNPAES exhibits long-term durability under 20% RH for 900 h. [ABSTRACT FROM AUTHOR]

Transition bimetallic compounds are exploited as high-capacity electrode materials for supercapacitors due to their abundant electroactive sites and electrical conductivity. However, it remains grand challenge to construct supercapacitor devices that deliver high energy density. Here, we report an attractive one-stone-two-birds strategy to develop metal organic frameworks (MOFs) derived cathodes and anodes consisting of zinc cobalt telluride integrated nitrogen doped carbon (ZnCoTe–N–C) and zinc cobalt nanoparticles encased nitrogen doped carbon nanotubes (ZnCo-NPs-N-CNTs), respectively. Particularly, ZnCoTe–N–C cathode exhibited high specific capacity of 192.77 mA h g−1, which was further improved by the presence of hierarchical molybdenum disulfides (MoS 2) nanosheets. Increased electrochemical active sites provided by MoS 2 nanosheets energizes both the capacity and stability of the electrode. Consequently, the ZnCoTe–N–C/MoS 2 electrodes showed a higher specific capacity of 342.55 mA h g−1 as well as excellent long-term stability. Besides, the ZnCo-NPs-N-CNTs demonstrated an initial capacity of 207.22 mA h g−1 and retained a high specific capacity even after 50 A g−1. The excellent electrochemical activity of the electrodes is attributed to the incorporation of redox rich bimetallic components and nitrogen rich carbon directly grown on the current collector, which reduces the dead volume and avoids volume expansion during charge discharge process. Finally, a hybrid asymmetric supercapacitor (HASCs) assembled using ZnCoTe–N–C/MoS 2 and ZnCo-NPs-N-CNTs delivered a high specific energy density and power density maintaining 93.6% of its capacitance after 20,000 cycles. This study expands a way to construct a hybrid supercapacitor with well-designed structure and superior performance for clean energy storage technologies utilizing minimum resources. [Display omitted] • ZnCo-MOF is utilized to obtain cathode and anode for hybrid supercapacitor. • Cathode: ZnCoTe–N–C/MoS 2 exhibited high specific capacity of 342.55 mA h g−1. • Anode: ZnCo-NPs-N-CNTs maintains excellent rate capability and stability. • HASCs delivered incredible specific energy density 108.41 W h kg−1. [ABSTRACT FROM AUTHOR]