Preparation of Nickel-Decorated and Nitrogen-Doped Carbon Nanotubes for Highly Efficient Hydrogen Evolution Reaction by Hydrothermal Method

Abstract

The unique structure of nickel-decorated and nitrogen-doped carbon nanotubes (Ni-NCNTs) was prepared by hydrothermal method. Nickel acetate tetrahydrate, graphitic carbon nitride (g-C3N4), and isopropanol were used as raw materials in this moderate method. The Ni-NCNTs were synthesized successfully by calcination under the protection of nitrogen. Under different pyrolysis temperatures, carbon nanotubes begin to form at 700 °C, and Ni-NCNTs also show the best hydrogen evolution reaction performance. At a current density of 10 mA/cm2, the overpotential has reached 378 mV and the Tafel slope of the sample is 139 mV/dec. This work successfully presented that it is feasible to introduce Ni nanoparticles and nitrogen into CNTs to enhance the electrocatalytic performance, while the doping of transition metals, Ni, and nitrogen improves the conductivity of CNTs and increases the contact of active sites.

Biomass-Derived Mo2C@N, P Co-Doped Carbon as an Efficient Electrocatalyst for Hydrogen Evolution Reaction

“…Figure a depicts their XRD patterns, along with those of commercial Mo 2 C. In Mo 2 C@NPC, the diffraction peaks at 2θ = 34.4, 38.0, 39.4, 52.1, 61.5, 69.6, 74.6, 75.5° corresponded to (100), (002), (101), (102), (110), (103), (112), and (201) facets of hexagonal Mo 2 C, respectively (JCPDS No: 35-0787). Raman spectra showed the characteristic bands of the carbon matrix at 1350 (D-band) and 1595 cm –1 (G-band), in which the similar I D / I G ratios of SKF-derived carbon, Mo 2 C@NC, and Mo 2 C@NPC indicated consistent graphitization with obvious structural defects (Figure b) . N 2 sorption isotherms were obtained to measure the specific surface areas of samples.…”

“…Figure 2a 2b). 28 N 2 sorption isotherms were obtained to measure the specific surface areas of samples. As depicted in Figure 2c, SKF-derived carbon exhibited an isotherm of type IV with a visible hysteresis loop, suggesting mesoporosity.…”

Atomized Copper-Decorated Nitrogen-Doped Porous Carbon Fibers as a Self-Standing Air Cathode for Flexible Zinc–Air Batteries

“…In X-ray diffraction (XRD) patterns, two peaks are visible at about 25 and 43° (Figure a), attributed to the lattice planes (002) and (100) of graphitic carbon for both samples of NC@g-C 3 N 4 -PAN-2P1 and Cu–NC@g-C 3 N 4 -PAN-2P1, respectively. , The absence of a copper diffraction peak is another evidence that no Cu large nanoparticles were produced, and that the copper inside the catalyst is in the form of discrete Cu atoms stabilized by N 4 coordination (Cu–N 4 ). Similar results are observed for the NC@PAN and Cu–NC@PAN, NC@g-C 3 N 4 -PAN-1P1 and Cu–NC@g-C 3 N 4 -PAN-2P1 systems (Figure S4a,b).…”

Simultaneous Control of Formation and Growth of Asphaltene Solids and Wax Crystals Using Single-Walled Carbon Nanotubes: an Experimental Study under Real Oilfield Conditions

“…Regarding the environmental aspects of nanostructure materials, risks to human health and the environment should be recognized for successful implementation of the carbon nanotubes in industry. Recent studies on the environmental effects of different types of nanoparticles disclose that the harmfulness of nanoparticles depends on specific physiochemical and environmental factors, which can be handled during the synthesis. , Applications of carbon-based nanoparticles at high volume may raise environmental and public health concerns. − However, many research studies verify that applications of carbon nanotubes at low concentrations do not cause any major adverse effects. − Furthermore, it has been found that functionalization of the carbon nanotubes makes them generally biocompatible without any risk to health. − …”