Nano-materials for engineering application

Nano-materials have undergone tremendous advancement in recent years, specifically in the field of engineering applications. To demonstrate these advances, seven high quality articles have been presented in this Special Issue, including one review and six original research works in various fields of engineering applications.

Reference [1], ‘Polypropylene-based nanocomposites for high voltage direct current (HVDC) cable insulation’ (by Adnan, M. et al.), presents an excellent review of different aspects of nanomaterials used in cable insulation for HVDC applications. The review shows that nanocomposites based on polypropylene exhibit enhanced dielectric properties, making them suitable for DC high voltage applications. Electrical double-layer, multicore and multi-region structure models are used for nanocomposite materials. Different fabrication methods have been improved, such as ‘Intercalation method’, ‘Sol gel method’ and ‘In situ polymerisation’. The paper presents DC breakdown characteristics for nanofiller loading, followed by the different types and effects for different nanocomposites.

In Reference [2], ‘Structure for fast photonic medium on application of space-division multiplexing (SDM) communication using SiO₂ doped with GeO₂, and F materials’ (by Behera, B. et al.), an advanced doping structure has been found suitable for applications in SDM communication for a fast photonic medium. A few-mode fibre has been introduced which shows a very small bit-error-rate, confirming the suitability of the advanced doping structure.

In Reference [3], ‘Nickel-cobalt-zinc ferrite nanoparticles for radio-frequency/terahertz frequency-selective surface application’ (by Arya, M. et al.), an advanced nanoparticle structure has been introduced for radio-frequency/terahertz frequency-selective surface applications. Terahertz time domain spectroscopy was used for analysis which revealed that the saturation magnetisation, remanent magnetisation and coercivity increased with an increase in temperature from 50 to 300 K.

Reference [4], ‘Investigation on the partial discharge characteristics of eco-friendly nanofluid insulation of corn oil nanofluid’ (by Shantha Kumar M. et al.), has revealed phase-resolved partial discharge analysis useful features of corn oil nanofluid. The oil is biodegradable in nature and, moreover, the analysis with different percentages of SiO₂ has shown improvements of partial discharge inception voltage, reduction of the repetition rate, equivalent time length, magnitude, lower discharge activity due to a rise in the wave shape etc. Thus, the authors have shown that it can be considered eco-friendly as well as an alternate for mineral oils.

Reference [5], ‘Switching transient-based state of ampere-hour prediction of lithium-ion, nickel-cadmium, nickel-metal-hydride and lead acid batteries used in vehicles’ (by Ray, D.K. et al.), presents a state of ampere-hour prediction using wavelet-based statistical analysis. The method can effectively predict charge status of the selected batteries in terms of their capacity at very early stages of operation.

Reference [6], ‘Understanding the enhanced electrorheological effect of reduced graphene oxide-supported polyaniline dielectric nanoplates by a comparative study with graphene oxide as the support core’ (by Yuan, J. et al.), presents a comparative study with graphene oxide as the support core. The authors have given guidelines for designing high-performance electrorheological materials useful for practical engineering applications.

Reference [7], ‘High frequency measurement of dielectric permittivity and antimicrobial properties of polyaniline and graphite oxide nanocomposites’ (by Shubha, L.N. et al.), presents advanced technology for measuring dielectric permittivity and antimicrobial properties of selected nanocomposites. In the frequency range of 100 MHz–3 GHz, the investigation was carried out using an radio frequency Impedance Analyser for analysing dielectric responses of the composites. The authors found that the dielectric response decreases with an increase in frequency. Less dielectric constant was found at high frequencies as variation in the field is very rapid for the dipoles to align themselves. The dielectric constant was 25 at 1 GHz and it was found to be around 2 at 3 GHz for Polyaniline/Graphite Oxide (PANI/GO) composites with 30 wt% of GO. At 30% doping of GO, both dielectric loss and constant were found to be at maximum.

Some of above works have been presented at the IET's Flagship event ‘Michael Faraday IET International Summit (3–4 October 2020)’ in their early stages. The complete issue covers a review of nanomaterials in HVDC systems, advances in structures, modelling, utilities and measuring techniques of nanomaterials in engineering applications. Both low frequency and high frequency-based features have been included. It is hoped that this issue will bring forward more emerging issues of nanomaterials in engineering applications and will provide potential directions for future research.