In Situ Formation of Metal Oxide Nanocrystals Embedded in Laser-Induced Graphene

Abstract

Hybrid materials incorporating the advantages of graphene and nanoparticles have been widely studied. Here we develop an improved cost-effective approach for preparation of porous graphene embedded with various types of nanoparticles. Direct laser scribing on metal-complex-containing polyimide film leads to in situ formation of nanoparticles embedded in porous graphene. These materials are highly active in electrochemical oxygen reduction reactions, converting O2 into OH(-), with a low metal loading of less than 1 at. %. In addition, the nanoparticles can vary from metal oxide to metal dichalcogenides through lateral doping, making the composite active in other electrocatalytic reactions such as hydrogen evolution.

A Highly Stretchable Microsupercapacitor Using Laser‐Induced Graphene/NiO/Co3O4 Electrodes on a Biodegradable Waterborne Polyurethane Substrate

“…[40,41] More importantly, the high-magnification image in Figure 1e reveals that LIG is decorated evenly with small round convex particles, indicating a portion of the hybrid NiO/Co 3 O 4 nanoparticles were distributed on surface. [33] The presence of hybrid NiO/Co 3 O 4 nanoparticles were further confirmed by Raman, X-ray photoelectron spectroscopy (XPS), and transmission electron microscope (TEM) analyses, as will be discussed later. [43,44] Moreover, the water contact angles ( Figure S2, Supporting Information) clearly reveal that the gelatin ion ink is a key factor in converting the hydrophilic pristine LIG (114.5° ± 2.3°) into hydrophobic (22.1° ± 0.8°) NiO/Co 3 O 4 /LIG, which is well suited for the penetration of WPU.…”

“…Whereas these characteristic peaks are not apparent after the transferring process since the mixed metal oxides were wrapped by the WPU thin layer. [33] Figure 2d displays the Ni 2p spectra of NiO/LIG, NiO/Co 3 O 4 / LIG, and NiO/Co 3 O 4 /LIG-WPU. [33] Figure 2d displays the Ni 2p spectra of NiO/LIG, NiO/Co 3 O 4 / LIG, and NiO/Co 3 O 4 /LIG-WPU.…”

“…[30] To further tap this device's potential, two conditions should be satisfied. [33,34] Different nanomaterials including transition metal oxides, carbides, and sulfides, which enable rich redox reactions, could be introduced into LIG to fabricate hybrid MSCs. [31,32] In this sense, simple LIG electrodes without any decoration are insufficient.…”

Incorporating Graphene into Fuel Cell Design

“…Each image represents a different atomic defect: six OH groups (a); four OH groups and one oxygen atom (b); two OH groups and two oxygen atoms (c); and three oxygen atoms (d) prepared correctly. Figure 9.6 depicts the fabrication process for LIG with metal particles embedded into the network [43]. Briefly, the polyaniline and metal complex is dissolved in an aromatic solvent and cast onto an aluminium dish, where it is vacuum dried.…”

“…The metal-impregnated 3D graphene networks display differing catalytic performances to the ORR, all of which are superior to its LIG parent material. A cobalt metal complex incorporated into the LIG reduces the ORR potential to that of Pt/C [43]. Thus, a potential method for cheaper ORR cathodes may be achievable through this route.…”