Enhancing the capacity of supercapacitive swing adsorption CO2 capture by tuning charging protocols
Published: Nanoscale, 2022, 14, 7980-7984
Published: J. Mater. Chem. A., 2021, 9, 16006-16015
To reduce greenhouse gas emissions in line with the Paris agreement, a significant shift towards electric vehicles and renewable resources is required. The development of improved energy storage devices, including those that can charge and discharge more quickly than the existing commercial batteries that are in our phones and laptops, will be critical to facilitate these changes. These fast-charging energy storage devices are known as electric double-layer capacitors (EDLCs).
Unfortunately, current state-of-the-art EDLCs store too little energy and so are not used widely. One way to increase the amount of energy stored in an EDLC is to improve the materials that they are made from. Recently, a new class of materials for use in these devices has been discovered known as two-dimensional metal-organic frameworks (2D MOFs). These materials are formed from the coordination of metal ions to organic molecules to form highly porous structures as shown below. Their high porosity means they are very promising for use in EDLCS, and initial investigations confirmed this promise. They could lead to improvements in EDLC performances, allowing for their more widespread implementation. However, much is still unknown about this class of materials.
In this study, we compare the performances of two members of this family of materials in EDLCs to gain more information on their behaviour in energy storage devices. Specifically, we investigate how changes in the chemical structure of 2D MOFs impact the performance. We also compare the performance of one family member with a current material used in state-of-the-art industrial EDLCs, porous carbons, to assess their potential for use in commercial devices. The insights presented in this work will help to improve EDLCs made using this new class of materials in the future.