Lakshman Neelakantan

Bio: Lakshman Neelakantan is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Corrosion & Materials science. The author has an hindex of 14, co-authored 40 publications receiving 496 citations. Previous affiliations of Lakshman Neelakantan include Ruhr University Bochum & Max Planck Society.

Effect of ternary element addition on the corrosion behaviour of NiTi shape memory alloys

Abstract: The goal of this study is to compare the corrosion behaviour of selected ternary nickel titanium (NiTi)-based alloys (Ni45Ti50Cu5, Ni47Ti50Fe3 and Ni39Ti50Pd11) with a binary, pseudoelastic Ni50.7Ti49.3 alloy. We examine the influence of the ternary elements on the corrosion behaviour using standard electrochemical techniques. All measurements were done in a physiological solution (0.9% NaCl) simulating a body temperature of 37 ± 1 °C. The influence of Cu and Pd addition on the surface oxide film was characterised by X-ray photoelectron spectroscopy (XPS). The results revealed that, the localised corrosion resistance of these ternary alloys is lower than the binary NiTi alloy. By comparing the different NiTi-based alloys, the following relation has been proposed for their localised corrosion resistances: NiTiCu < NiTiFe < NiTiPd < NiTi. Depth profiling by XPS showed that the surface oxide film on all the investigated NiTi-based alloys is mainly of TiO2, however, the NiTiPd and NiTiCu alloys showed metallic ternary element distributed within TiO2 layer.

Anodic Aluminum Oxide Template Assisted Synthesis of Copper Nanowires using a Galvanic Displacement Process for Electrochemical Denitrification

Abstract: Metallic nanowires find widespread applicability, and a variety of synthesis techniques are available. Among these, template assisted deposition offers flexibility in terms of material and dimensio...

A Review on TiO2 Nanotubes: Influence of Anodization Parameters, Formation Mechanism, Properties, Corrosion Behavior, and Biomedical Applications

Abstract: In this article, influence of anodization parameters on the formation of tubes, tube dimensions, formation mechanism, properties of TiO2 nanotubes (TNT), and their applications in biomedical field are reviewed. The fabrication of TNT of a different shape such as pore size, length, and wall thickness by varying anodization parameters including electrolytes, pH, voltage, electrolyte bath temperature, and current density is examined and discussed. The crystallographic nature of the nanotube obtained by various methods has also been discussed. Finally, the article concludes by examining the key properties including the corrosion aspect and various applications in biomedical field in depth.

Electrocatalytic reduction of nitrate - a step towards a sustainable nitrogen cycle.

Abstract: Nitrate enrichment, which is mainly caused by the over-utilization of fertilisers and industrial sewage discharge, is a major global engineering challenge because of its negative influence on the environment and human health. To solve this serious problem, many technologies, such as the activated sludge method, reverse osmosis, ion exchange, adsorption, and electrodialysis, have been developed to reduce the nitrate levels in water bodies. However, the applications of these traditional techniques are limited by several drawbacks, such as a long sludge retention time, slow kinetics, and undesirable by-products. From an environmental perspective, the most promising nitrate reduction technology is enabled to convert nitrate into benign N2, and features low cost, high efficiency, and environmental friendliness. Recently, electrocatalytic nitrate reduction has been proven by satisfactory research achievements to be one of the most promising methods among these technologies. This review provides a comprehensive account of nitrate reduction using electrocatalysis methods. The fundamentals of electrocatalytic nitrate reduction, including the reaction mechanisms, reactor design principles, product detection methods, and performance evaluation methods, have been systematically summarised. A detailed introduction to electrocatalytic nitrate reduction on transition metals, especially noble metals and alloys, Cu-based electrocatalysts, and Fe-based electrocatalysts is provided, as they are essential for the accurate reporting of experimental results. The current challenges and potential opportunities in this field, including the innovation of material design systems, value-added product yields, and challenges for products beyond N2 and large-scale sewage treatment, are highlighted.

Impact of surface topography and coating on osteogenesis and bacterial attachment on titanium implants.

Abstract: Titanium (Ti) plays a predominant role as the material of choice in orthopaedic and dental implants. Despite the majority of Ti implants having long-term success, premature failure due to unsuccessful osseointegration leading to aseptic loosening is still too common. Recently, surface topography modification and biological/non-biological coatings have been integrated into orthopaedic/dental implants in order to mimic the surrounding biological environment as well as reduce the inflammation/infection that may occur. In this review, we summarize the impact of various Ti coatings on cell behaviour both in vivo and in vitro. First, we focus on the Ti surface properties and their effects on osteogenesis and then on bacterial adhesion and viability. We conclude from the current literature that surface modification of Ti implants can be generated that offer both osteoinductive and antimicrobial properties.