## 5 Applications
### Energy Storage
If these temperatures are sufficiently high, there is a possibility of material evaporation. The temperature rise may also result in release of thermal stress of the material that, in turn, results in different microstructures of the synthesized material. [PERSON] et al. [130] reported the P-milling method to prepare few layers graphene using different milling media such as germanium oxide, iron oxide, zinc oxide, boron nitride, and tungsten carbide. The relation between number of layers formed and inductive capacity of milling media were investigated. The nanocomposite of germanium (Ge) nanoparticles wrapped with few layered graphene (Ge@FLG) via dielectric barrier discharge plasma (DBDP) assisted method was demonstrated by [PERSON] et al. [40]. In this study, nanocomposites with preprocessed (P-milled Ge powder for 5 h and expandable graphite heated at 1000 \({}^{\circ}\)C) and DBDP for 10 h in the presence of argon atmosphere exhibited superior anode performance for lithium-ion battery compared to nanocomposites prepared by the same precursors, but without the DBDP and conventional ball milling route. The aggregation of particles started after exceeding the milling time more than 10 h resulted in a decrease in the electrochemical performance. The Ge@FLG nanocomposite showed nearly 90 \(\Omega\) lower resistance for charge transportation and capacity of 846.3 mA h g\({}^{-1}\) with 86% of retention rate. In the study by [PERSON] et al. [129], a comparative electrochemical performance of anode material prepared by Sn-C nanocomposite via dielectric barrier discharge plasma assisted milling (DBDP) (PM) and conventional milling (CM) method was reported. A Sn-C composite prepared by PM and CM with 10 h of milling (PM-10 h and CM-10 h, respectively, showed different microstructural composition. While a non-homogenous dispersion of Sn particles in graphite matrix was observed in CM-10 h, the Sn-C composite showed homogenous dispersion of multi-scale Sn particles in graphite matrix via PM-10 Sn-C composite. In plasma state, the charged particles impacted the Sn powder surface with high speed and high energy, resulting in local temperature rise followed by release of the thermal stress. The expansion resulting from the release of thermal stress was uniformly distributed and observed to be homogeneously embedded in graphite matrix. This technique showed that the graphite layers were not damaged as in the case of CM. Coulombic efficiency and capacity at initial stage was observed to be 61.8% and 818.7 mA h g\({}^{-1}\) in PM-10 h composite while 47.9% and 727.4 mA h g\({}^{-1}\) observed in CM-10 h composite. Thus, the PM-10 h composite exhibited superior electrochemical performance than the CM-10 h composite. The required milling time is much shorter in the P-milling process than other milling techniques. Therefore, the P-milling route has significant advantages in synthesizing the material with nano scale and, particularly, resulting in different microstructures due to high chemical reactivity, large surface area, and low temperature operation. The Mg-based hydrogen (H\({}_{2}\)) storage materials and group IV-A elements synthesized by the P-milling method were reported to exhibit remarkable performance as energy storage materials [131]. In another study, a nanocomposite of carbon quantum dots and cobalt sulfide (CQDs/CoS\({}_{2}\)) prepared by the ball milling assisted hydrothermal route reported by [PERSON] et al. [132]. In this study, CQDs were prepared by the microwave radiation assisted method. The nanocomposite with highly porous morphology with surface attached CQDs provides a large surface area, extra ion storage spaces, and fast ion transportation pathways may promote to enhance the supercapacitor performance. The electrochemical characteristics of CQDs/CoS\({}_{2}\) nanocomposite and pure CoS\({}_{2}\) (without decoration of CQDs) were tested by the cyclic voltammetry (CV), galvanostatic charge\(-\)discharge (GCD), and electrochemical impedance spectroscopy (EIS) studies.