MXene coupled with molybdenum dioxide nanoparticles as 2D-0D pseudocapacitive electrode for high performance flexible asymmetric micro-supercapacitors

Recently,two-dimensional(2D)transition metal carbides and carbonitrides(MXenes),have shown great potential in micro-supercapacitors(MSCs).However,the maximum voltage output of symmetric MXene MSCs is limited to 0.6 V due to the oxidation effects at high anodic potentials.Herein,we developed asymmetric micro-supercapacitors(AMSCs)based on titanium carbide MXene(Ti_(3)C_(2)Tx)and MXene-MoO_(2) electrodes with an enlarged voltage window of 1.2 V,which is twice wider than that of symmetric MXene MSCs.The 2D-0D MXene-MoO_(2) microelectrode is fabricated by homogenous dispersing zerodimensional(0D)MoO_(2) nanoparticles into MXene layers to impede layers stacking and MoO_(2) nanoparticles aggregation.Notably,the AMSCs delivered good electrochemical performances of areal capacitance of ~19 mF cm^(-2) and volumetric capacitance of 63 F cm^(-3) at a scan rate of 2 mV s^(-1),and high energy density of 9.7 mW h cm^(-3) at a power density of 0.198 W cm^(-3).The AMSCs also presented exceptionally mechanical flexibility under different bending states and excellent cyclic stability,with 88% capacitance retention after 10000 cycles at a discharge current density of 0.5 mA cm^(-2).For practical application,the serially connected AMSCs are fully affordable to power electronics,which is beneficial for soft and wearable power devices.

基于苍耳子的堆积型疏松阳极用于提升微生物燃料电池的长期运行性能（英文）

基于堆积型阳极的微生物燃料电池因材料成本低且在大型反应器中适用性强,在实际应用中具有较好前景.但是,堆积结构常带来堵塞问题,因此基于堆积型阳极的微生物燃料电池通常稳定性较差.本文中,我们用生物炭堆积的疏松阳极来提升堆积型阳极微生物燃料电池的长期稳定性.生物炭由苍耳子直接炭化获得,保持了苍耳子特殊的外形,保证了其在制备成堆积型阳极后具有疏松的结构和良好的导电性.用于微生物燃料电池时,该生物炭堆积型阳极获得了与常用的活性炭材料堆积阳极相当的产电性能,且该燃料电池在150天的运行时间内产电性能无明显下降,而作为参照的活性炭堆积阳极燃料电池的性能呈现极大下降.这种良好的稳定性是因为生物炭堆积阳极的疏松结构减少了长期运行过程中的堵塞现象.这种基于苍耳子的生物炭材料可以作为高效稳定的微生物燃料电池阳极材料,有望在实际应用中大型化长期运行.