Ultrathin nickel hydroxide nanosheet arrays grafted biomass-derived honeycomb-like porous carbon with improved electrochemical performance as a supercapacitive material

Abstract

Three-dimensional hierarchical honeycomb-like activated porous carbon pillared ultrathin Ni(OH)2 nanosheets (Ni(OH)2 NSs@HAPC) for use as supercapacitor materials were facilely synthesized. With an aid of pine cone flowers as a biomass source, HAPC conducting scaffolds were prepared by the alkali treatment and pyrolysis methods under an inert gas atmosphere. Subsequently, the Ni(OH)2 NSs were synthesized evenly on the surface of HAPC via a solvothermal method. The resulting HAPC and Ni(OH)2 NSs@HAPC composite materials offered free pathways for effective diffusion of electrolyte ions and fast transportation of electrons when employed as an electrode material. The Ni(OH)2 NSs@HAPC composite electrode exhibited excellent electrochemical properties including a relatively high specific capacitance (Csp) value of ~ 916.4 F/g at 1 A/g with good cycling stability compared to the pristine HAPC and Ni(OH)2 NSs electrodes. Such bio-friendly derived carbon-based materials with transition metal hydroxide/oxide composite materials could be a promising approach for high-performance energy storage devices because of their advantageous properties of cost effectiveness and easy availability.

Rationally designed transition metal hydroxide nanosheet arrays on graphene for artificial CO2 reduction

“…1 and Supplementary Note 1 ) and transition metal cations (Ni 2+ , Fe 3+ , Cu 2+ , Co 2+ ) leads to a firm adsorption of transition metal cations on the surface of GO 21 . At the beginning of the growth process, hexamethylenetetramine (HMTA) as a hydrolyzing agent can tardily decompose to liberate OH – ions, and then transition metal cations react with OH – ions to form dense transition metal hydroxides nuclei on the surface of GO 17 , 28 . The high density of transition metal hydroxide nuclei conduce to the vertical growth of nanosheets because the steric hindrance from adjacent seeds can hinder the in-plane direction growth 29 .…”

“…The analysis of Raman spectroscopy in Fig. 2b shows that peaks at 1353 and 1590 cm −1 are assigned to the D-band and G-band of GR, and the peak at 468 cm −1 is ascribed to Ni(OH) 2 28 , 38 . The well-identified Ni(OH) 2 and GR peaks in Ni(OH) 2 -10%GR composite indicate that Ni(OH) 2 nanosheet arrays have successfully grown on the GR platform.…”

“…2a, the diffraction peaks of Ni(OH) 2 at 8.7°, 17.3°, 33.4°, and 59.9°can be indexed to (003), (006), (101), and (110) planes of α-Ni(OH) 2 (JCPDS no. 38-0715) 28,35 . Two peaks at low angles (<20°) clearly indicate the layered structure of Ni (OH) 2 32 .…”

Comparison of acid exfoliators in carbon nanosheets synthesis from stinging nettle (Urtica dioica) for electrochemical applications

“…The preparation of nanostructured materials from waste materials has drawn tremendous interest in recent years 16 , 17 . Many researchers have demonstrated that carbon materials for use as adsorbent or electronic materials can be synthesized by potassium hydroxide from low-cost waste materials such as rice husk 18 , Acai stone 19 , corncob 20 , pine cone flower 21 , banana peel 22 , water hyacinth 23 , waste coffee grounds 24 , pineapple leaf fibre 25 , bamboo 26 , wood sawdust 27 , peanut shell 28 – 30 , jute 31 , gulfweed 32 and pomelo peel 33 . Nettle ( Urtica dioica ) is a plant widely distributed in many areas of Asia, Europe, America and Africa 34 .…”

In situ hydrothermal synthesis of MnO2 nanowires/wood derived activated carbon hollow fibers composite and its application in supercapacitor

“…However, previous studies showed that wood carbon materials exhibited moderate capacitive performance (Ma et al 2018). Therefore, a large amount of research has been devoted to maximally improving the low specific capacitance of biomassed carbon materials by adding heteroatoms (Peng et al 2016) or transition metal oxides (TMO) (Nagaraju et al 2017, Jiang et al 2018. TMO has the favorable capacitive characteristics and environmental friendliness (Augustyn et al 2014).…”