Building Carbon-Based Versatile Scaffolds on the Electrode Surface to Boost Capacitive Performance for Fiber Pseudocapacitors.

In order to fabricate high performance fiber pseudocapacitors, the trade-off between high mass loading and high utilization efficiency of pseudocapacitive materials should be carefully addressed. Here, a solution that is to construct a carbon-based versatile scaffold is reported for loading pseudocapacitive materials on carbonaceous fibers. The scaffold can be easily built by conformally coating commercial pen ink on the fibers without any destruction to the fiber skeleton. Due to the high electrical conductivity and abundant macropore structure, it can provide sufficient loading room and a high ion/electron conductive network for pseudocapacitive materials. Therefore, their loading mass and utilization efficiency can be increased simultaneously, and thus the as-designed fibrous electrode displays a high areal capacitance of 649 mF cm-2 (or 122 mF cm-1 based on length), which is higher than most of the reported fiber pseudocapacitors. The simple and low-cost strategy opens up a new way to prepare high performance portable/wearable energy storage devices.