Dr Nimai Mishra, Assistant Professor, Department of Chemistry, SRM University-AP, Andhra Pradesh, along with his research group pursuing PhD under him-Ms V.G.Vasavi Dutt and Mr Syed Akhil- have published a research article titled “Enhancement of Photoluminescence and Stability of CsPbX3 (X= Cl, Br, and I) Perovskite Nanocrystals with Phthalimide Passivation” in the Journal “Nanoscale” (The Royal Society of Chemistry, Impact Factor-7.8).
Caesium lead halide perovskite nanocrystals (CsPbX3 NCs) have been the flourishing area of research in the field of photovoltaic and optoelectronic applications because of their excellent optical and electronic properties. However, they suffer from low stability and deterioration of photoluminescence (PL) properties post-synthesis. One of the ways to minimize the surface defects in the surface treatment with suitable ligands is to achieve the NCs with superior PL properties for light-emitting applications.
In this article, Dr Mishra’s research group demonstrates that incorporating an additional ligand can further enhance the optical properties and stability of NCs. Here, we introduced phthalimide as a new surface passivation ligand into the oleic acid/oleylamine system in situ to get near-unity photoluminescence quantum yield (PLQY) of CsPbBr3 and CsPbI3 perovskite NCs. We observed, phthalimide passivation dramatically improves the stability of CsPbCl3, CsPbBr3, and CsPbI3 NCs under ambient light and UV light. The PL intensity is recorded for one year which showed a dramatic improvement for CsPbBr3 NCs. Nearly 11% of PL can be retained even after one year for phthalimide passivated samples, on the other hand, the PL of as-synthesized NCs completely diminishes in four months. CsPbCl3 NCs exhibit 3 times higher PL with phthalimide and retain 12% PL intensity even after two months while PL of as-synthesized NCs completely diminishes by then. Under continuous UV light illumination, the PL intensity of phthalimide passivated NCs is well preserved while the as-synthesized NCs exhibit negligible PL emission in 2 days. About 40% and 25% of initial PL is preserved for CsPbBr3 and CsPbCl3 NCs in the presence of phthalimide. CsPbI3 NCs with phthalimide exhibit PL even after 2 days while the PL is rapidly declined for as-synthesized NCs in the first 10 hours. The presence of phthalimide in CsPbI3 NCs could maintain stability even after a week while the as-synthesized NCs under transition to non-luminescent phase within 4 days.
Furthermore, blue, green, yellow, and red-emitting diodes by using CsPbCl1.5Br1.5, CsPbBr3, CsPbBr1.5I1.5, CsPbI3 NCs respectively are fabricated by drop-casting NCs onto blue LED lights which show the great potential of the use of these phthalimide passivated NCs in the field of display and light technologies.
Read the full paper here: https://pubs.rsc.org/en/content/articlelanding/2021/nr/d1nr03916d
Heat stress negatively affects crop yield and its impact has increased over time. Researchers in India study this situation with utmost priority. Consequently, Dr Ghanshyam Kumar Pandey, Assistant Professor in the Department of Economics at SRM University-AP has co-authored a paper with Pratap S Birthal and et. al titled “Benefits of irrigation against heat stress in agriculture: Evidence from wheat crop in India” in the journal Agricultural Water Management, Vol 255, having an Impact factor 4.02.
Applying the fixed effects regression technique to the highly spatially disaggregated district-level data from 1966–67 to 2011–12. This paper has assessed the impact of heat stress on wheat production in India and concurrently evaluated the role of irrigation in offsetting its harmful impact. The study has brought out three key highlights:
(i) Heat stress negatively impacts crop yield, and the impact has increased over time.
(ii) Irrigation, besides its contribution towards improving crop yield, also moderates the harmful impact of heat stress, but over time its effectiveness has declined.
(iii) The measure of heat stress built on multiple aspects of excess temperature (i.e., intensity, persistence, and frequency) explains variation in crop yield better than working on a single aspect of it.
Given the increasing scarcity of irrigation water and rising temperature, these findings suggest the need for exploring technological and policy options for improving irrigation water use, efficiency, and breeding of crops for heat tolerance and low water footprints.
This research paper is written in collaboration with ICAR-National Institute of Agricultural Economics and Policy Research, PUSA, New Delhi. Dr Ghanshyam’s future projects are focused on climate change and agriculture, and the effect of climate change on the livestock sector in India.
Read the full paper here: https://doi.org/10.1016/j.agwat.2021.106950
Controlled loading of MoS2 on hierarchical porous TiO2 for enhanced photocatalytic hydrogen evolution
Ever since the breakthrough research on H2 photogeneration from water using TiO2 under UV-light irradiation, an enormous amount of research has been conducted on photochemical H2 evolution using different semiconductor-based photocatalysts. Consequently, a research paper titled “Controlled Loading of MoS2 on Hierarchical Porous TiO2 for Enhanced Photocatalytic Hydrogen Evolution” has been published by Prof Ranjit Thapa, Professor of Physics, SRM University – AP, as a co-author, in The Journal of Physical Chemistry C, having an Impact Factor of 4.189.
In this work, Prof Thapa describes three important factors for helping in the generation of hydrogen using proposed MoS2/TiO2 catalyst, (i) TiO2 for effective charge transfer, (ii) MoS2 for plasmon induction (iii) large surface area and active sites. It was shown that hierarchical porous TiO2 can be interfaced successfully with marigold-flower-like MoS2 flakes with intriguing photophysical properties, viz., visible-light response, controlled electron−hole recombination, and sustainable H2 production over prolonged light irradiation due to the synergic effect of flowerlike MoS2 and the fibrous wormhole mesoporous channel of TiO2. Further, the researchers have used density functional theory (DFT) to identify the active sites and calculated the change in Gibbs free energy (ΔGH). “We have also studied the charge density difference to understand about electron transfer pathway. The change free energy of hydrogen adsorption (ΔGH*) is a good indicator to estimate the hydrogen evolution activity in the acidic medium. From the DFT study, it is clear that O sites of MPT heterostructure are more favourable for HER reactivity”, said Prof Ranjit Thappa.
Social implications of the research:
In the last few decades, with the decline in non-renewable resources and increasing environmental pollution, significant attention has been given to renewable and clean energy domains. Hydrogen is considered one of the most suitable energy carriers due to its higher energy density per unit mass in comparison to other chemical fuels. In recent times, photocatalytic fission (Photocatalysis is a process in which light energy is used to drive pairs of chemical reactions. Through the absorption of light, an excited electron/hole pair is produced) of water has been considered an attractive solution for solar to chemical H2 energy conversion. Also, the process of water splitting is highly endothermic. Therefore, the development of an excellent, stable, efficient, and economical photocatalyst for ultrahigh H2 production efficiency is paramount to researchers.
This work is done in collaboration with the Department of Energy and Environmental Engineering, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India.
Prof Ranjit Thapa is doing an investigation to find the possibility of hydrogen evolution reaction (HER) on multiple borophene analogues (α, β12, χ3) on all unique sites. Understanding the role of the coordination number of the boron atoms in the borophene analogues with the HER efficiency, and studying the pathways Volmer-Tafel (V-T) on each site to understand the completed HER process on borophene analogues are his future research projects. His research group is also interested to identify the role of sigma and pi-electron occupancy on the V-T pathway.
Read the full paper here: https://doi.org/10.1021/acs.jpcc.1c01922
Dr Nimai Mishra’s research group develops a new synthetic strategy to make ultra-stable CsPbBr3 perovskite nanocrystals for light-emitting application
Dr Nimai Mishra, Assistant Professor in the Department of Chemistry, SRM University-AP, Andhra Pradesh, along with his research group comprising of students pursuing PhD under his supervision, Mr Syed Akhil and Ms V.G.Vasavi Dutt have published a research article titled “Bromopropane as a Novel Bromine Precursor for the Completely Amine Free Colloidal Synthesis of Ultra-Stable and Highly Luminescent Green-Emitting Cesium Lead Bromide (CsPbBr3) Perovskite Nanocrystals” in the Journal “Nanoscale” (The Royal Society of Chemistry, Impact Factor-7.8).
Recently, lead halide perovskite nanocrystals (PNCs) have attracted intense interest as promising active materials for optoelectronic devices. However, their extensive applications are still hampered by poor stability in ambient conditions. In this work, Dr Mishra’s research group report an open-atmospheric, facile, efficient, completely amine-free synthesis of caesium lead bromide perovskite nanocrystals using a novel bromine precursor, bromopropane, which is inexpensive, and available at hand. Their finding concludes that the PLQY can maintain 83% of their initial one even after 120 days. Furthermore, after 96 h of continuous irradiation by UV light with 365 nm (8 W/cm2) in the open ambient condition the photoluminescence (PL) intensity showed retention of 68% of its original value with no significant change in full width at half-maximum, whereas amine-based sample retains only 5% of its original PL intensity. Furthermore, Dr Mishra’s group has fabricated stable down-converted LED devices with these perovskite nanocrystals.
“More importantly, the present work demonstrates the synthesis of ultra-stable CsPbBr3 NCs which can be an ideal candidate for display applications”, says Dr Nimai Mishra.
Read the full paper: https://pubs.rsc.org/en/Content/ArticleLanding/2021/NR/D1NR03560F#!divAbstract
The advent of the industrial revolution increased the dependency of humans on fossil fuels which led to an increase in environmental degradation. While alternative energy sources such as wind, solar and hydro seem to be good options, their uncertainty in delivering the power made Dr Sujith Kalluri, Assistant Professor in the Electronics and Communication Engineering Department and his PhD scholar Chanakya Karra at SRM University-AP prefer batteries as a viable option. “Application-driven Industrial-scale Manufacturing of Li/Na-ion Battery Cathodes” is a paper published by Dr Sujith Kalluri and Mr Chanakya Karra in the Journal of The Electrochemical Society having an Impact Factor of 3.721 as part of their project to develop zero-emission energy methods.
Through this article as a platform, the authors focus on three aspects of energy storage devices that are essential while the world is catapulted to upgrade itself from fossil fuels to electric vehicles. From a battery level perspective, they have discussed the dependence of the battery industry on lithium-ion technology and its repercussions. As a solution, they suggest the distribution of the dependency on sodium-ion technology owing to its adaptability and wide availability. From the cathode level perspective, the paper suggests co-precipitation through the CSTR as a customized solution to address the setbacks in the synthesis process and additive manufacturing as a preferred solution to cater for the desired electrode design specifications that would comply with the needs of future generations and the industry. Till the battery energy storage system paves the way for Na to take over, we can reckon on SC-NCM cathode material to serve the needs.
Read the full paper here: https://iopscience.iop.org/article/10.1149/1945-7111/abfab6/pdf
More about the Battery research project of SRM University-AP:https://srmap.edu.in/seas/electronics-and-communication-engineering/research-areas/battery-research/
Biochar has an enormous potential in addressing global issues and can act as a catalyst in achieving sustainable development goals (SDGs). Dr Lakhveer Singh, Assistant professor in the Department of Environmental Science, SRM University-AP has co-authored and published a paper on the title “Biochar for environmental sustainability in the energy-water-agroecosystem nexus” in the research journal “Renewable and Sustainable Energy Reviews” with an Impact factor of 14.98.
Global warming, management of soil health, remediation of contaminated wastewater, and sustainable alternate source of energy are the major challenges of the 21st century. Biochar produced from waste biomass (crop residues, algal biomass, municipal waste, etc.) has dual advantages of waste management along with its application in different sectors. Biochar addition to soil improves soil health, porosity and aeration which mitigates greenhouse gas emission from soil.
In this manuscript, Dr Lakhveer Singh discusses the potential of biochar for bioenergy production (biogas and biological hydrogen production), greenhouse gases mitigation, carbon sequestration in soils, and wastewater remediation are discussed in detail along with the challenges and future prospects of biochar. This work has been executed in collaborations with the National Institute of Hydrology, Jal Vigyan Bhawan, Roorkee; J.C. Bose University of Science and Technology; YMCA, Faridabad; and IIT Delhi.
Dr Singh is an Editorial Board member of the Journal of Biomass Conversion and Biorefinery – Springer (I.F. 2.60) and a Guest Editor for Bioresource Technology Reports- Elsevier.
Read the full paper here: https://www.sciencedirect.com/science/article/abs/pii/S136403212100664X
A research study to predict the waning of the second wave of COVID-19 in Uttar Pradesh, Delhi, Karnataka, Maharashtra, Andhra Pradesh, Tamil Nadu, Kerala & West Bengal
In the current pandemic situation, a pertinent question is the estimate of time by which the second wave of COVID – 19 spread could be contained and normalcy would return. In this context, Prof. D. Narayana Rao, Pro-Vice-Chancellor, SRM University – AP initiated the study to predict the End-Time of COVID – 19 in the states of Uttar Pradesh, Delhi, Karnataka, Maharashtra, Andhra Pradesh, Tamil Nadu, Kerala & West Bengal. Dr. Soumyajyoti Biswas of SRM University – AP along with 4 B.Tech Students: Mr. Anvesh Reddy, Mr. Hanesh Koganti, Mr. Sai Krishna, and Mr. Suhas Reddy have carried out an interesting study to predict the end time of the second wave of COVID – 19 spread in these states. Study employed Susceptible – Infected – Recovered (SIR) Model making use of the information on the COVID – 19 affected people and the number of recovered people, the data which the state governments make them available. SRM Team made use of these data employed SIR Model and applied the methods of Machine Learning. The End -Times of the spread of COVID-19 for different states are given in the following table:
|States||Uttar Pradesh||Delhi||Karnataka||Maharashtra||Andhra Pradesh||Tamil Nadu||Kerala||West Bengal|
|End-time||May 27||May 28||July 1||July 13||July 16||July 26||August 12||September 2|
|Errors||-2 days, + 3 days||-2 days, + 2 days||– 6 days, + 5 days||-7 days, + 7 days||-16 days, + 28 days||-17 days, + 33 days||-14 days, + 14 days||-30 days, + 30 days|
End-Time is defined as the date on which the number of COVID affected cases get reduced to 5% of the peak number of cases occurred in the particular state.
The model is also validated with the actuals occurred in the States of Delhi and Uttar Pradesh.
Uttar Pradesh: Peak of 37,944 was n 24th April 2021 and 5% of the peak number is 1897 and is predicted to occur on 27th May with an error of -2 days to +3 days
Actuals: 27th May: 3179, 28th May: 2276, 29th May: 2014, 30th May: 1864
Delhi: Peak of 28,935 was on 20th April 2021 and 5% of the peak number is 1490 and is predicted to occur on 28th May with an error of – 2 days to + 2 days
Actuals:26th May: 1491, 27th May : 1072, 28th May : 1141
The validation mentioned of the end-times of the second wave of COVID-19 spread increases our confidence level to the predictions made for other states also.
It can be noticed that in the States of West Bengal, Kerala, Tamil Nadu, and Andhra Pradesh, the second wave of COVID-19 continues to spread for longer periods and errors are large compared to the other states of Uttar Pradesh, Delhi, Karnataka, and Maharashtra. Perhaps, these factors could be attributed to the large gatherings that have occurred in the 4 states on several occasions.
Prof Narayana Rao said that these predictions mentioned above could help in estimating the impact on medium and small business sectors. In the education sector, it could help in planning the academic sessions, examinations, etc. It could also help to plan necessary medical infrastructure for healthcare in different states.
The details of the study can be found in [2105.13288] Machine learning predictions of COVID-19 second wave end-times in Indian states (arxiv.org)
Dr Satish Anamalamudi, Assistant Professor, in the Department of Computer Science and Engineering has published a research paper titled “Cooperative Caching Scheme for Machine-to-Machine Information-Centric IoT Networks” in the IEEE Canadian Journal of Electrical and Computer Engineering. The research paper is co-authored by Dr Mohammed Saeed Alkatheiri and Dr Eesa Al Solami of University of Jeddah, Saudi Arabia and Dr Abdur Rashid Sangi of Yibin University, China.
According to the authors, Information-centric networks (ICNs), a foreseen future Internet architecture, focuses on the application content rather than its hosting location. With this, the existing Internet protocol (IP)-based host-centric communication model can be transformed into a content-centric communication model with the support of in-network caching, name-based routing, and location-independent content domain names. Recently, ICN is proposed to be a potential Internet architecture for Internet-of-Things (IoT) networks due to minimal retrieval delays and reduced load on the data producer. Content retrieval from IoT nodes plays a prominent role in enhancing the performance of the ICN-IoT networks. The in-network caching of ICN enhances the data availability in the network, overcome the issue of single-point failure, and improve IoT devices power efficiency. In this work, the authors explore a cooperative caching scheme for information-centric-IoT networks to optimize the cache hit with the support of a caching network topology model, a content popularity model, and an exogenous request access model.
Dr Satish says that ICN proposes to shift the existing complex Internet model to a simple and generic one. This approach considers the content as the first-class network citizen. In ICN, contents are addressed and routed by their unique names and are decoupled from the address of the node storing it. In this way, consumers ask for information by its name rather than its locality address. In ICN, every content is identified by using a unique, persistent and location-independent name. A wide set of IoT applications is inherently information-centric. In fact, the majority of IoT applications target data regardless of its source. For instance, environmental monitoring applications are oblivious to the information origin. ICN is a promising candidate for IoT environments. It can natively support IoT scenarios while improving data dissemination and reducing network complexity.
Dr Satish Anamalamudi had been a Research Engineer with Huawei Technologies, Beijing, China. He also worked with the Huaiyin Institute of Technology (HYIT), Huai’an, China, until February 2018. He is currently an Assistant Professor with the Department of Computer Science and Engineering, SRM University-AP, Andhra Pradesh. His research interests include the common-control-channel design for MAC and routing protocols in cognitive radio ad hoc networks, MAC, and routing protocol design of Internet of Things (IoT) and 5G networks.
Read the full paper here: https://doi.org/10.1109/ICJECE.2020.3046844
Dr Imran Pancha, Assistant Professor in the Department of Biological Sciences, has recently published a paper titled “Deep eutectic solvents and Ionic liquid assisted hydrolysis of microalgal biomass: A promising approach towards sustainable biofuel production” in the celebrated Journal of Molecular Liquids (2021): 116264 (Impact Factor-5.065). The study was conducted in association with Akshay Kulshrestha, Sandhya Mishra, and Arvind Kumar from CSIR-CSMCRI
Microalgae is recently considered one of the promising biomasses for the production of renewable energy such as biodiesel and bioethanol. Microalgae are tiny photosynthetic organisms that utilise atmospheric CO2, water and sunlight to produce carbohydrates and lipids, which can be converted into renewable fuels. Compared to higher plants, microalgae is a good platform for bioethanol production as they do not contain any lignin in their cell composition, which makes pre-treatment for biomass hydrolysis easy. In the present study, Dr Pancha and his team explored the use of green solvents ionic liquids (ILs) and deep eutectic solvents (DESs) for microalgal hydrolysis. They observed that among the eight tested ionic liquids, ethyl ammonium nitrate (EAN) resulted in the highest saccharification yield of 95.5%. Whereas, among hydrophobic deep eutectic solvents, menthol: lactic acid (Me: LA) exhibited the highest saccharification yield of 85.7% and also did not require any additional high temperature or other pre-treatments for biomass hydrolysis, indicating as the potential solvent system for microalgal biomass hydrolysis. Overall, the present study results indicated that the identified IL and DES could be used as a green and sustainable alternative for the pre-treatment of microalgal biomass for bioethanol production.
Due to limited fossil fuel reserve as well as environmental issues like high greenhouse gas emission and other environmental problems, finding green and sustainable energy resource is of prime importance for today’s world. To solve this problem, microalgae are among the best resources for producing renewable resources due to it’s high growth rate and photosynthetic ability. Microalgae also have the ability to obtain nutrients from various wastewater, so they also do not require fresh water for cultivation. However, commercial-scale production of microalgae-based biofuels faces various problems such as cultivation cost, downstream processing for biofuel production etc. In this regard, in the present work, Dr Pancha demonstrated the use of ILs and DESs for pre-treatment of microalgal biomass for reducing sugar production, which can be further utilised to produce bioethanol.
Dr Pancha and his research group are further devoted to understanding the molecular mechanism behind the accumulation of energy reserved compounds in the microalgae and developing a sustainable biorefinery process to extract biofuels and other industrially relevant compounds from single microalgal biomass.
Read the full paper: https://doi.org/10.1016/j.molliq.2021.116264
Ms Sreelekha Bhuvaneswari, a BSc physics final year student, in SRM University AP, Andhra Pradesh, filed a patent for her work titled “A fibre material with moisture retention capacity with thermal tolerance and a method for manufacture” under the guidance of Dr Sabyasachi Mukhopadhyay, Assistant Professor, Department of Physics, SRM University-AP.
The project, with the patent application number 202141023375, develops a methodology to design a fabric cloth that would replace the use of air conditioners. This cloth design is inspired by Saharan silver ants which regulate their body temperatures in the scorching desert heat and also from the cooling properties of clay. This research would significantly scale down the usage of AC and other cooling devices in warm places, thus reducing the use of electricity and emission of greenhouse gases to the environment. As this cloth would be environment friendly with long durability and cost-efficiency, Sreelekha hopes that this research would bridge the socioeconomic divide of haves and have-nots between communities.
“I am grateful to Dr Sabyasachi sir for his constant help and guidance along the way. There were several failed models, but he believed in the concept and that inspired me to go forward with the project,” said Ms Bhuvaneswari. “The facilities at the University made the process seamless; once the proposal was made, the procedure was automated. I thank the officials of SRM University-AP for believing in my proposal and helping me get through the procedures smoothly. If it were not for the facilities available at my university, I could not have finished the design,” She added.