Agasthiyaraj Lakshmanan

Bio: Agasthiyaraj Lakshmanan is an academic researcher from SRM University. The author has contributed to research in topics: Materials science & Air filter. The author has an hindex of 1, co-authored 4 publications receiving 5 citations.

Synthesis of CTAB-Functionalized Large-Scale Nanofibers Air Filter Media for Efficient PM2.5 Capture Capacity with Low Airflow Resistance

Abstract: Ambient particulate matter air pollution has become a serious environmental issue and poses grave threats to public health globally. The indoor and outdoor air protection could be achieved by filte...

Low-Basis Weight Polyacrylonitrile/Polyvinylpyrrolidone Blend Nanofiber Membranes for Efficient Particulate Matter Capture

Abstract: Particulate matter (PM) in air frequently poses a serious threat to human health. Smaller PM can easily enter into the alveolus and blood vessels with airflow. This work reports the first polyacrylonitrile (PAN)/polyvinylpyrrolidone (PVP) polymer blend nanofiber filter media for effectively capturing PM. Density functional theory (DFT) calculations are used to investigate the effect of the blending of two polymers on the dipole moment and the electrostatic potential. Based on the DFT calculations of the intermolecular interactions between nanofibers and PM, the PAN/PVP heteromolecular percentage is considered for experimental synthesis, which can provide better performance in the filtration of pollutants. The composite PAN/PVP fiber network was successfully developed and optimized to cope with complex environments during the actual filtration process. The role of the blending ratio of PAN and PVP in wt % was explored on PM2.5 capture, and the refined ratio overcame the conflict between high filtration efficiency and low air pressure resistance. The air filter medium PAN/PVP (6:2) possesses an extremely high air filtration efficiency of 92% under a very low pressure drop of 18 Pa for a 0.5 g m–2 basis weight. Both polar and nonpolar functional groups in blend nanofibers promoted significantly the electrostatic attraction and improved the filtration efficiency under static and dynamic airflow. The PAN/PVP nanofiber membranes maintain outstanding air filtration under different temperature and humidity conditions. This study will shed light on the fabrication of high-efficiency low-basis weight nanofiber filter media as an end product.

One-step synthesis of highly reactive g-C3N4

Abstract: Graphitic carbon nitride (g-C3N4) with well-controlled properties are the key for photocatalysis water splitting and organic pollutant degradation. A facile template-free synthesis method was utilized to optimize the polymerization temperature of melamine and urea for the preparation of highly active g-C3N4. The polymerization was carried out at different temperatures and ramping rate in tightly sealed crucible system with open air conditions. The crystalline and tri-s-triazine periodicity was significantly improved with increasing polymerization temperature. The results demonstrated that graphitic carbon nitride could not be fully formed below 550 °C. It was also found that the precursors and heating rate had a big influence on the photocatalytic activities. Higher photocatalytic activities were achieved by g-C3N4 synthesized from urea at a lower heating rate.

Electrospun Nanofiber Membranes for Air Filtration: A Review

Abstract: Nanomaterials for air filtration have been studied by researchers for decades. Owing to the advantages of high porosity, small pore size, and good connectivity, nanofiber membranes prepared by electrospinning technology have been considered as an outstanding air-filter candidate. To satisfy the requirements of material functionalization, electrospinning can provide a simple and efficient one-step process to fabricate the complex structures of functional nanofibers such as core–sheath structures, Janus structures, and other multilayered structures. Additionally, as a nanoparticle carrier, electrospun nanofibers can easily achieve antibacterial properties, flame-retardant properties, and the adsorption properties of volatile gases, etc. These simple and effective approaches have benefited from the significate development of electrospun nanofibers for air-filtration applications. In this review, the research progress on electrospun nanofibers as air filters in recent years is summarized. The fabrication methods, filtration performances, advantages, and disadvantages of single-polymer nanofibers, multipolymer composite nanofibers, and nanoparticle-doped hybrid nanofibers are investigated. Finally, the basic principles of air filtration are concluded upon and prospects for the application of complex-structured nanofibers in the field of air filtration are proposed.

Does the Government’s Environmental Attention Affect Ambient Pollution? Empirical Research on Chinese Cities

Abstract: Environmental pollution has attracted growing government attention. We employ a series of panel data regression models to measure and analyze the impact of environmental attention of 284 prefecture-level municipal governments on ambient pollution in China. The results show that: (1) The improvement of government environmental attention can curb ambient pollution. (2) The impact of government environmental attention on ambient pollution is heterogeneous in the difference of regional and local environmental pollution severity. (3) Government environmental attention inhibits ambient pollution through green development and industrial upgrading. The conclusions of this paper provide evidence and implications for environmental regulation in developing countries and cities.