Graphene is a promising electrode material not only due to its intrinsic properties like good electrical conductivity, high mechanical strength and high chemical stability, but also because of its high theoretical surface area of 2630 m 2 g −1 . In this report, the effect of CVD parameters to the growth of high quality graphene on metal substrates by using plasma enhanced chemical vapor deposition (PECVD) was extensively studied. Interestingly, synthesizing high quality graphene by PECVD technique is not only depending on the CVD parameters, but also depending on the catalysts and its plasma sources. It was found that Ni and Cu are the most favored metal catalysts for PECVD graphene growth. With high solubility of carbon (> 0.1 at. %), Ni effectively promote the growth of multilayer graphene by PECVD. However, large-area synthesis has made relatively inexpensive Cu as one of the most attractive substrates for monolayer graphene growth. Further details on the potential use of different transition metal catalysts in synthesizing graphene and consequently the specific usage of graphene based devices are discussed in this report.

Supercapacitors, based on fast ion transportation, are among the most promising energy storage solutions that can deliver fast charging-discharging within seconds and exhibit excellent cycling stability. The development of a good electrode material is one of the key factors in enhancing supercapacitor performance. Graphene (G), an allotrope of carbon that consists of a single layer of carbon atoms arranged in a hexagonal lattice, elicits research attention among scientists in the field of energy storage due to its remarkable properties, such as outstanding electrical conductivity, good chemical stability, and excellent mechanical behavior. Furthermore, numerous studies focus on 2D materials that are analogous to graphene as electrode supercapacitors, including transition metal dichalcogenides (TMDs). Recently, scientists and researchers are exploring TMDs because of the distinct features that make 2D TMDs highly attractive for capacitive energy storage. This study provides an overview of the structure, properties, synthesis methods, and electrochemical performance of G/TMD supercapacitors. Furthermore, the combination of G and TMDs to develop a hybrid structure may increase their energy density by introducing an asymmetric supercapacitor system. We will also discuss the future prospect of this system in the energy field.

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Supercapacitors are highly promising energy devices with superior charge storage performance and a long lifecycle. Construction of the supercapacitor cell, especially electrode fabrication, is critical to ensure good performance in applications. This work demonstrates direct growth of vertically aligned carbon nanotubes (CNTs) on Fe–Ni based metal alloy foils, namely SUS 310S, Inconel 600 and YEF 50, and their use in symmetric vertically aligned CNT supercapacitor electrodes. Alumina and cobalt thin film catalysts were deposited onto the foils, and then CNT growth was performed using alcohol catalytic chemical vapour deposition. By this method, vertically aligned CNTs were successfully grown and used directly as a binder-free supercapacitor electrode to deliver excellent electrochemical performance. The device showed relatively good specific capacitance, a superior rate capability and excellent cycle stability, maintaining about 96% capacitance up to 1000 cycles.

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