One of the promising supercapacitors for next-generation energy storage is zinc-ion hybrid supercapacitors. For the anode materials of the hybrid supercapacitors, three-dimensional (3D) graphene frameworks are promising electrode materials for electrochemical capacitors due to their intrinsic interconnectivity, excellent electrical conductivity, and high specific surface area. However, the traditional route by which 3D graphene frameworks are synthesized is energy- and time-intensive and difficult to apply on a large scale due to environmental risks. Here, we describe a simple, economical, and scalable method of fabricating grafoil (GF) directly into a graphite–graphene architecture. Both synthesizing of a porous structure and functionalization with interconnected graphene sheets can be simultaneously achieved using electrochemically modified graphite. The resultant graphite electrode provides a high capacitance of 140 mF/cm2 at 1 mA/cm2, 3.5 times higher than that of pristine grafoil, keeping 60.1% of its capacitance when the current density increases from 1 to 10 mA/cm2. Thus, the method to produce 3D graphene-based electrodes introduced in the current study is promising for the applications of energy storage devices.

Background : The cultivation of wild greens in a forest farming system is an attractive alternative to wild harvesting, due to its much lower production cost compared with conventional cultivation, and its provision of a second income to the landowner. Yet little is known about the conditions that would maximize the growth and antioxidant activities of wild greens in a forest farming system. Thus, this study was conducted to evaluate the optimal conditions that would maximize antioxidant activities of Ligularia fischeri (Ledeb.) Turcz., being cultivated in three different cultivation systems in Korea. Methods and Results : After the fibrous roots of L. fischeri were planted in three different cultivation systems, this study was conducted to assess the effect on health-related properties such as total phenolic contents, flavonoids, DPPH (1,1-diphenyl-2-picrylhydrasyl) free radical scavenging activities and reducing power. From these harvests in different sites, extracts were prepared using methanol. Total phenolic content in forest farming system (1.061 ㎎·GAE/㎖) was higher than that in other products harvested in conventional and greenhouse system (0.666㎎·GAE/㎖). Also, flavonoid content was higher in forest farming system (0.124 ㎎·QE/ ㎖), compared to conventional and greenhouse system (0.084 ㎎·QE/㎖). Conclusions : Antioxidant activity and cultivation system seem to correlate with total polyphenol and flavonoid contents.