1成果简介 
　　锌离子混合超级电容器（ZIHSCs）因其兼具电池与电容器的优良特性而备受关注。本文，长春工业大学杨希佳、黄宇欣等在《Journal of Alloys and Compounds》期刊发表名为“T-Nb2O5/rGO@CC anode for ultralong-life zinc-ion hybrid supercapacitors”的论文，研究采用水热法与高温煅烧法相结合的协同策略，制备了以柔性碳布（CC）为基底的纳米球结构T-Nb₂O₅复合阳极材料，其表面涂覆有还原石墨烯氧化物（rGO）（T-Nb₂O₅/ rGO@CC），并搭配由废弃柑橘皮制备的分级超介孔活性炭阴极（ACcp@CC）。
　　rGO涂层结构抑制了充放电过程中内部纳米结构的体积膨胀，有效提升了机械稳定性。同时，rGO的三维导电网络有效补偿了Nb₂O₅固有的较差导电性。构建的ZIHSC在1 mA cm-2下展现出718.56 mF cm-2的电容值，并在1 mW cm-2下实现399.20 μWh cm-2的最大能量密度。此外，经过50,000次超长循环后，容量保持率仍达104.17%。组装的柔性器件不仅具备优异的机械性能，还在1 mA cm-2电流密度下实现389.89 mF cm-2的比电容，可为各类电子设备提供长期供电。本研究为铌基电极材料稳定复合结构的设计及超长循环性能研究提供了坚实的理论依据。
　　2图文导读

  
　　Fig. 1. The schematic illustration of the preparation of the T-Nb2O5/rGO@CC anode and ACcp@CC cathode, as well as the assembly process of the flexible ZIHSC.

　　图2. (a-c) SEM images of acid-treated CC at distinct resolutions. (d-f) SEM images of T-Nb2O5/rGO@CC at distinct resolutions. (g-j) SEM-EDS images of T-Nb2O5/rGO@CC. (k-m) TEM and HRTEM images of the materials took from T-Nb2O5/rGO@CC.

　　图3. Characterization of T-Nb2O5/rGO@CC: (a) XRD patterns, (b) Raman spectrum, (c) XPS survey, (d) Nb 3d, (e) O 1 s, (f) C 1 s, XPS spectrum of Nb2O5@CC: (g) Nb 3d, (h) O 1 s, (i) C 1 s.

　　图4. Characterization of ACcp: (a-c) SEM image of ACcp. (d) XRD patterns. (e) XPS survey spectra. (f) C 1 s spectrum. (g) Raman spectrum. (h) Nitrogen adsorption desorption isotherm of ACcp. (i) Aperture distribution of ACcp.

　　图5. (a, b) Three-electrode CV and GCD curves of T-Nb2O5/rGO and single-hydrothermal Nb2O5. (c) Comparison of EIS between T-Nb2O5/rGO@CC and single-hydrothermal Nb2O5@CC. (d) CV curves of T-Nb2O5/rGO@CC//ACcp at diverse current densities. (e) GCD curves of T-Nb2O5/rGO@CC//ACcp at diverse scanning rates. (f) EIS of T-Nb2O5/rGO@CC//ACcp@CC. (g) Cyclic stability test of aqueous T-Nb2O5/rGO@CC//ACcp@CC ZIHSC at 50 mA cm-2.

　　图 6. (a-b) SEM image of T-Nb2O5/rGO@CC after 50000 cycles. (c) XRD patterns of T-Nb2O5/rGO@CC after 50000 cycles. (d-e) SEM image of ACcp@CC after 50000 cycles. (f) XRD patterns of ACcp@CC after 50000 cycles.

　　图7. (a) Schematic diagram of flexible T-Nb2O5/rGO@CC//Zn(CF3SO3)2/PVA// ACcp ZIHSC. (b) CV curves. (c) GCD curve. (d) EIS for flexible devices. (e) CV curves of flexible ZIHSC at varying bending angles. (f) Illustration of the flexible apparatus driving a timer.
　　3小结 
　　综上所述，通过水热法和高温煅烧法，将还原石墨烯氧化物包覆的球形T-Nb₂O₅纳米颗粒沉积在柔性CC表面作为阳极。同时，通过处理柑橘皮获得ACcp@CC正极材料。采用Zn(CF₃SO₃)₂/PVA作为凝胶型电解质，组装的柔性可穿戴ZIHSC展现出卓越的电化学性能，在1 mA cm⁻²电流密度下实现惊人的比容量389.89 mF cm⁻²，同时保持优异的机械柔韧性和稳定性。更值得注意的是，其循环性能卓越，经过50,000次充放电循环后，循环保持率达104.17%。本研究为未来Nb₂O₅复合电极材料的研究提供了宝贵参考，表明其具有非常可观的商业潜力。
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