A research paper titled “Nitrogen doping derived bridging of Graphene and Carbon Nanotube composite for oxygen electroreduction” has been published by Prof Ranjit Thapa, Professor of Physics, SRM University – AP, as a co-author, in International Journal of Energy Research, having Impact Factor of 5.164.

In this work, the research group investigated the origin of high catalytic activity of oxidic-N configuration in nitrogen-doped CNT and graphene heterostructure using density functional theory (DFT). We have plotted the free energy profile of the oxygen reduction reaction (ORR) to estimate the thermodynamic overpotential and catalytic performance of the respective active sites. The overpotential is related to the quantifying parameter ∆GOH (with R2 = 0.98) and the π electron density at the Fermi level, defined as an electronic descriptor, which is highly correlated with the ∆GOH with R2 value 0.96. For various N doped configurations, we correlated the ∆GOH values with π electron density at the Fermi level and found that the carbon site adjacent to the oxide-N configuration is a more prominent site for ORR. Further, we show that the oxidic-N configuration in the heterostructure of graphene and CNT is the ideal configuration, which gives a lower overpotential of 0.54 eV for ORR on adjacent carbon sites. Therefore, the charge transfer occurs from underneath CNT to graphene and increases the value of π electron density at the Fermi level which leads to the higher catalytic performance of the active site.

In the early 20th century, fuel cells were invented and their global impact has not reached up to its regular commercialization when compared with battery technology. The fuel cell device could be a powerful technique to generate electricity for large energy demand without greenhouse gas emissions. However, other major hurdles in the commercialization of fuel cell devices are the cost of platinum (as a catalyst), its poisoning and stability. Recently, carbon-based materials such as graphene, carbon nanotubes and activated carbon have been evolved as metal-free low-cost catalysts due to their (i) high abundance/yield (ii) reactivity towards oxygen just by introducing impurities like heteroatoms or other metals. However, identifying an efficient design principle to search optimal doping configurations in various carbon systems is a grand challenge for researchers.

This work is done in collaboration with Research Institute, SRM Institute of Science & Technology, Kattankulathur-603203, Chennai (India).

In future, the study aims to propose the effective design principle for various doped carbon systems as a catalyst to identify the optimal active sites and configurations for ORR. The role of π orbital in carbon systems such as graphene, graphene nanoribbons, carbon nanotube, etc is very important and can be a general electronic descriptor to define catalytic activity. Also, π electron descriptors and machine learning algorithms based combined approach can boost the search for ideal carbon catalyst for ORR with low DFT cost.

Read the full paper here: https://doi.org/10.1002/er.7179

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

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.

Dr. Satyajit Gupta (PI), IIT Bhilai, and Dr Sabyasachi Mukhopadhyay (Co-PI), Department of Physics, SRM University-AP has signed a Memorandum of Understanding for the DST (Indo-Israel Joint Research Co-operation-IIJRC) sponsored project entitled “A HALIDE PEROVSKITE BASED PHOTOANODE FOR OXYGEN EVOLUTION REACTION USING A MOLECULAR DIODE IN A HYBRID NANOMETER SCALE PROTECTION LAYER”, Sanction Order NO. – DST/INT/ISR/P-28/2020(G). The project is a bilateral project and Foreign PI is Dr Eran Edri, Department of Chemical Engineering, Ben-Gurion University of the Negev, Israel. This MoU will help Dr Mukhopadhyay to utilize the fund under this project as co-PI, and the facility of IIT Bhilai to complete the objective of the project.

The Objectives of the MoU are to promote effective application of resources through Indo-Israel Joint Research Co-operation-(IIJRC) sponsored project, promote mentorship and research guidance, and cooperate in educational/research areas of mutual interest. It also aims to promote international collaborations through International travel of Party, hosting International delegates, and through a student exchange programme between Indian Institute/Universities and Ben-Gurion University of the Negev, Israel.

The MoU will provide a platform to share and exchange Best Practices, and facilitate exchange programmes for students. Dr Satyajt Gupta and Dr Sabyasachi Mukhopadhyay will provide training and development for students working under this joint project.

The Department of Physics, SRM University-AP organized a “One-day National Symposium on High Energy Physics” on Saturday, May 1, 2021. The session was held through online mode in the presence of honourable leaders of the university, faculty members, and attendees from various fields of interest. Prof V S Rao, the Vice-Chancellor, SRM University-AP, welcomed the gathering with a brief overview of the university’s inception and quick progress in the field of research.

Three talks at the pedagogical level were organised for a wider audience, especially for the students of basic sciences and engineering streams. The first speaker, a Padma Shri awardee, Prof Rohini Godbole, who is a theoretical particle physicist at Indian Institute of Science (IISc), Bengaluru expounded on “Status of Particle Physics: in light of Nobel Prizes of 2013 and 2015”. She talked about the Higgs Boson’s theoretical postulate, for which the Nobel Prize in Physics was granted in 2013. According to studies, it was the final missing element in the Standard Model’s periodic table (SM). Her paper incorporated the experimental finding of the Neutrino Oscillation, as well as many compelling pieces of evidence that led to the 2015 Nobel Prize.

In the afternoon session, the talks were on the burgeoning field of Dark Matter physics and Gravitational-wave astronomy. Prof Basudeb Dasgupta from Tata Institute of Fundamental Research (TIFR), Mumbai apprised the participants on “The Mystery of Invisible Mass”. The deep understanding and expertise of Prof Dasgupta in the interfaces of particle physics, astrophysics, and cosmology with a particular emphasis on dark matter and neutrino physics as a theoretical physicist at the Tata Institue of Fundamental Research (TIFR) enlightened the audience. He stated that the human beings are able to see only 20% of the universe’s celestial objects; the remaining 80% are unseen and are referred to as “dark matter.” In his words, “Billions of years after the Big Bang, all we can see is the cloud’s surface, where the light is scattered.” Prof Basudeb, is a frequent speaker at prestigious international and national conferences and is a youth icon for aspiring physicists and scientists.

The final lecture of the day was delivered by Prof Bala Iyer from International Centre for Theoretical Sciences (ICTS), Bengaluru on “The Detection of Gravitational Waves and the Dawn of Multi-messenger Astronomy” at 4.00 pm. Prof Iyer is currently the Simons Visiting Professor at ICTS-TIFR Bangalore and co-PI of the LIGO-India Scientific Collaboration. He coaches and guides young minds interested in astrophysics, cosmology, and fundamental physics. Prof Iyer did a presentation on the discovery of gravitational waves from a binary black hole in 2015, which was a watershed moment and necessitated the launch of a new multi-messenger astronomy with the potential to have a significant impact on astrophysics. “Any relativistic theory of gravity must be consistent with the special relativity principle. Gravity’s effect cannot travel faster than the speed of light. If an item’s gravitational field changes, the changes propagate over space and take a certain amount of time to reach the object “, he added.

The symposium that aimed to discuss the current status of exciting research topics of High Energy Physics concluded with a Q&A session. This has proved that the faculty members and participants were highly inspired and motivated after attending the symposium and listening to the scholars.

Pre-Event Release: https://srmap.edu.in/events/national-symposium-on-high-energy-physics-2021/