Preparation Of Nanoscale Materials Research Articles

Nanofabrication and Sensing Technology: from the Interface‐Mediated Mechanism Point‐of‐View

AbstractIn recent years, the field of sensing technology has experienced notable advancements, where sensing devices have emerged as pivotal tools in enhancing operational efficiency, cutting costs, and bolstering security across diverse sectors. In this context, the preparation of nanoscale materials and structures, including colloidal particle synthesis and lithographic structure fabrication will be discussed. The significance of managing the interface environment in sensor designs, with nanofabrication advancements enabling the development of innovative sensing devices, is highlighted. Control over the interface environment is argued not only dictates the capability of sensor designs but also opens avenues for next‐generation sensor fabrication and integration. By focusing on the interface‐mediated mechanism, this approach offers a comprehensive roadmap of this research area, its challenges and potential solutions, and prospective opportunities.

Ultrasonic-assisted, rapid preparation of mesoporous MnCO3 for electrochemical supercapacitor applications: A novel approach

Accounting for the methods opted in the preparation of nanoscale materials with high surface rea, average pore size and volume needs high energy and time-consuming processes. This work discloses a quick, scalable, and simple co-precipitation method for synthesizing MnCO3 for use in supercapacitors as a working electrode using MnSO4 and (NH4)HCO3 as the manganese and carbonate sources, respectively. As-synthesized sample is subjected to sonication at different periods for evaluating the effect of capacitance and the size of MnCO3 particles. Investigations using X-ray diffraction and X-ray photoelectron spectroscopy proves that MnCO3 can form the rhodochrosite phase and microscopical analyses reveals that nanograins smaller than 10 nm aggregated into spherical particles that were submicron in size. N2 adsorption–desorption isotherm isotherms validates the mesoporosity of MnCO3. The Galvanostatic charge–discharge cycling and cyclic voltammetry techniques examine the capacitance characteristics of mesoporous MnCO3 in both 0.1 Mg(ClO4)2 and Na2SO4 aqueous solutions. Mesoporous MnCO3 delivers a specific capacitance of 188F g−1 and 124F g−1 at a specific current of 0.33 A g−1 in both Mg(ClO4)2 and Na2SO4 aqueous solutions with a loading level of 1.5 mg cm−2. Additionally, mesoporous MnCO3 shows strong rate capability and stable cycle-life over 10,000 cycles. These demonstrates the mesoporous nanomaterials with high surface area and volume can enhance the energy storage capacitance of a supercapacitor.

Microemulsion nanoreactor applied for the synthesis of iron-based catalysts for carbon nanotube formation

Catalysts play an important role in the production of carbon nanotubes, and the preparation of catalysts has always been a hot topic. In this study, microemulsion nanoreactor was constructed and applied for the first time to prepare carbon nanotube catalysts. The natural “pool” formed with the oil phase as an external substance and the surfactant as the boundary provides a reactor stable at the nanometer level for the co-precipitation reaction of Fe (NO3)3•9H2O and Al (NO3)3•9H2O, and the precipitation reaction is more uniform and sufficient. The active ingredient of the catalyst has better dispersion. Carbon nanotubes are nucleated with the active ingredient as the site and have a smaller and uniform diameter. Moreover, we want to control the size of the reactor by changing the surfactant concentration. The best performance was obtained when the surfactant content is 14 %, with the hydration diameter of microemulsion prepared of about 50 nm, the particle size and specific surface area of catalyst of about 60 nm and 255.97 m2/g. The diameter of carbon nanotubes grown under the catalyst was mainly distributed between 6 and 13 nm, with low defect degree. The results show that the reverse microemulsion method has unique advantages in the preparation of nano-scale materials, and this study provides a reference for the preparation of carbon nanotubes catalysts using microemulsion nanoreactor.