In the field of construction, structural supercapacitors (SSCs) have been widely noticed due to their simultaneous functions of load-bearing and energy storage. Unfortunately, the currently available electrodes for SSCs are still aimed at application scenarios such as electronics and electric vehicles, and while their performance is good, they are not applicable to the construction sector, which is massive in scale and extremely cost-sensitive industry. Herein, after trade-off between cost and electrochemical performance, a novel low-cost 3D nanomaterial was designed through a facile approach aimed at increasing the areal energy density of SSCs. By growing Mg-Co double hydroxide nanomaterials directly on nickel foam, we achieved a large areal capacitance of 2577 mF/cm at 5 mA/cm (1136.7 F/g at 2.2 A/g). It also exhibits good cycling stability with a capacitance retention of 82.4 % after 10,000 cycles. In addition, SSCs using magnesium-cobalt double hydroxides achieves a high energy density of 285.6 μWh/cm at a power density of 6.31 mW/cm, which is superior to previously reported structural devices. This demonstrates that Mg-Co double hydroxide electrode has good suitability with SSCs and effectively improves the areal energy density of SSCs. Our proposed method also provides a faster and more reliable pathway for low-cost electrode preparation in SSCs, which may lead to the development of a new generation of SSCs.

中文翻译：

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用于土木工程高能量密度结构超级电容器的基于镁钴双氢氧化物的低成本电极


在建筑领域，结构超级电容器（SSC）因其同时具有承重和储能的功能而受到广泛关注。不幸的是，目前可用的SSC电极仍然针对电子和电动汽车等应用场景，虽然其性能良好，但不适用于规模庞大且成本极其敏感的建筑行业。在此，在成本和电化学性能之间进行权衡后，通过一种简便的方法设计了一种新型低成本3D纳米材料，旨在提高SSC的面能量密度。通过直接在泡沫镍上生长 Mg-Co 双氢氧化物纳米材料，我们在 5mA/cm 电流下实现了 2577 mF/cm 的大面积电容（在 2.2A/g 电流下为 1136.7F/g）。它还表现出良好的循环稳定性，10,000 次循环后电容保持率为 82.4%。此外，使用镁钴双氢氧化物的SSC在6.31mW/cm的功率密度下实现了285.6 μWh/cm的高能量密度，优于之前报道的结构器件。这表明Mg-Co双氢氧化物电极与SSCs具有良好的适应性，有效提高了SSCs的面能量密度。我们提出的方法还为 SSC 中的低成本电极制备提供了更快、更可靠的途径，这可能会导致新一代 SSC 的开发。