Zeolitic imidazolate framework (ZIF)-derived porous carbon materials for supercapacitors: an overview Rabia Ahmad, a Usman Ali Khan, a Naseem Iqbal * a and Tayyaba Noor b The present analysis focuses on the synthetic methods used for the application of supercapacitors with various mysterious architectures derived from zeolitic imidazolate frameworks (ZIFs). ZIFs represent an emerging and unique class of metal–organic frameworks with structures similar to conventional aluminosilicate zeolites, consisting of imidazolate linkers and metal ions. Their intrinsic porous properties, robust functionalities, and excellent thermal and chemical stabilities have resulted in a wide range of potential applications for various ZIF materials. In this rapidly expanding area, energetic research activities have emerged in the past few years, ranging from synthesis approaches to attractive applications of ZIFs. In this analysis, the development of high-performance supercapacitor electrodes and recent strategies to produce them, including the synthesis of various heterostructures and nanostructures, are analyzed and summarized. This analysis goes via the ingenuity of modern science when it comes to these nanoarchitecture electrodes. Despite these significant achievements, it is still difficult to accurately monitor the morphologies of materials derived from metal–organic frameworks (MOFs) because the induction force during structural transformations at elevated temperatures is in high demand. It is also desirable to achieve the direct synthesis of highly functionalized nanosized materials derived from zeolitic imidazolate frameworks (ZIFs) and the growth of nanoporous structures based on ZIFs encoded in specific substrates for the construction of active materials with a high surface area suitable for electrochemical applications. The latest improvements in this field of supercapacitors with materials formed from ZIFs as electrodes using ZIFs as templates or precursors are discussed in this review. Also, the possibility of usable materials derived from ZIFs for both existing and emerging energy storage technologies is discussed. 1. Introduction In addition to batteries, supercapacitors are relatively new devices that are capable of producing high power rates. Although supercapacitors deliver thousands of times more power than batteries, they cannot hold the same amount of charge as batteries, normally 3–30 times less. Hence, super- capacitors can prove to be ideal for certain applications that need power outbursts, but not those where high energy storage capacity is required. 1–3 Supercapacitors can also be used in battery-based energy storage systems (ESS) to congure their energy and power capabilities, boost the capacity, achieve the energy and power requirements and increase the lifespan. 4,5 The power output of supercapacitors compared to electro- lytic capacitors is very low, while their specic energy is many times higher. 3,6 Supercapacitors are of interest because they are an improvement over batteries and conventional capacitors, which can store signicant quantities of energy at lower power densities (1 kW kg 1 ) due to their storage mechanism. Fig. 1 shows that a battery can provide almost 150 W h kg 1 of energy density, which is basically around 10 times the capability of an electrochemical capacitor. In terms of energy density, batteries do not have the potential to reach electrochemical capacitor values. Batteries barely reach 200 W kg 1 , approximately 20 times less than the estimated output of electrochemical capacitors. 7,8 This is because batteries suffer drawbacks such as a sudden decrease in efficiency due to fast charging cycles or cold ambient temperatures; they are expensive to sustain and have short service lives. 2,9 However, Ragone plots do not clarify some other key parameters, such as total cost, cycle stability or safety. To obtain a better understanding of the benets and drawbacks of a certain energy storage technology, these criteria must be described separately. Hence, this is a very signicant factor when considering that supercapacitors are not only able to discharge in a small a US-Pakistan Center for Advanced Studies in Energy (USPCAS-E), National University of Sciences and Technology (NUST), Islamabad 44000, Pakistan. E-mail: naseem@ uspcase.nust.edu.pk; Tel: +92-51-90855281 b School of Chemical and Materials Engineering (SCME), National University of Sciences and Technology (NUST), Islamabad 44000, Pakistan Cite this: RSC Adv. , 2020, 10, 43733 Received 7th October 2020 Accepted 13th November 2020 DOI: 10.1039/d0ra08560j rsc.li/rsc-advances This journal is © The Royal Society of Chemistry 2020 RSC Adv. , 2020, 10, 43733–43750 | 43733 RSC Advances REVIEW Open Access Article. Published on 08 December 2020. Downloaded on 9/10/2021 1:12:37 PM. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. View Article Online View Journal | View Issue