Gaurav Gupta

Bio: Gaurav Gupta is an academic researcher from Newcastle University. The author has contributed to research in topics: Oxygen evolution & Nanoparticle. The author has an hindex of 10, co-authored 28 publications receiving 258 citations. Previous affiliations of Gaurav Gupta include Imperial College London & Lancaster University.

Aggregation and adhesion of gold nanoparticles in phosphate buffered saline

Abstract: In applications in medicine and more specifically drug delivery, the dispersion stability of nanoparticles plays a significant role on their final performances. In this study, with the use of two laser technologies, dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA), we report a simple method to estimate the stability of nanoparticles dispersed in phosphate buffered saline (PBS). Stability has two features: (1) self-aggregation as the particles tend to stick to each other; (2) disappearance of particles as they adhere to surrounding substrate surfaces such as glass, metal, or polymer. By investigating the effects of sonication treatment and surface modification by five types of surfactants, including nonylphenol ethoxylate (NP9), polyvinyl pyrrolidone (PVP), human serum albumin (HSA), sodium dodecyl sulfate (SDS) and citrate ions on the dispersion stability, the varying self-aggregation and adhesion of gold nanoparticles dispersed in PBS are demonstrated. The results showed that PVP effectively prevented aggregation, while HSA exhibited the best performance in avoiding the adhesion of gold nanoparticle in PBS onto glass and metal. The simple principle of this method makes it a high potential to be applied to other nanoparticles, including virus particles, used in dispersing and processing.

Transformations of nanomaterials in the environment.

Abstract: Increasing use of engineered nanomaterials with novel properties relative to their bulk counterparts has generated a need to define their behaviors and impacts in the environment. The high surface ...

Durability challenges of anion exchange membrane fuel cells

Abstract: As substantial progress has been made in improving the performance of anion exchange membrane fuel cells (AEMFCs) over the last decade, the durability of AEMFCs has become the most critical requirement to deploy competitive energy conversion systems. Because of different operating environments from proton exchange membrane fuel cells, several AEMFC-specific component degradations have been identified as the limiting factors influencing the AEMFC durability. In this article, AEMFC durability protocol, the current status of AEMFC durability, and performance degradation mechanisms are reported based on the discussion during the US Department of Energy (DOE) Anion Exchange Membrane Workshop at Dallas, Texas, May 2019. With additional recent progress, we provide our perspectives on current technical challenges and future action to develop long-lasting AEMFCs.

Green hydrogen from anion exchange membrane water electrolysis: a review of recent developments in critical materials and operating conditions

Abstract: Hydrogen production using water electrolysers equipped with an anion exchange membrane (AEM), a pure water feed and cheap components such as platinum group metal-free catalysts and stainless steel bipolar plates (BPP) can challenge proton exchange membrane (PEM) electrolysis systems as the state of the art. For this to happen the performance of the AEM electrolyzer must match the compact design, stability, H2 purity and high current densities of PEM systems. Current research aims at bringing AEM water electrolysis technology to an advanced level in terms of electrolysis cell performance. Such technological advances must be accompanied by demonstration of the cost advantages of AEM systems. The current state of the art in AEM water electrolysis is defined by sporadic reports in the academic literature mostly dealing with catalyst or membrane development. The development of this technology requires a future roadmap for systematic development and commercialization of AEM systems and components. This will include basic and applied research, technology development & integration, and testing at a laboratory scale of small demonstration units (AEM electrolyzer shortstacks) that can be used to validate the technology (from TRL 2–3 currently to TRL 4–5). This review paper gathers together recent important research in critical materials development (catalysts, membranes and MEAs) and operating conditions (electrolyte composition, cell temperature, performance achievements). The aim of this review is to identify the current level of materials development and where improvements are required in order to demonstrate the feasibility of the technology. Once the challenges of materials development are overcome, AEM water electrolysis can drive the future use of hydrogen as an energy storage vector on a large scale (GW) especially in developing countries.