chinmoy-das-research

The Department of Chemistry is thrilled to announce the paper “Mechanochemically-induced glass formation from two-dimensional hybrid organic-inorganic perovskites”, published by Dr Chinmoy Das, Assistant Professor in the reputed Q1 Journal Chemical Science with an 8.4 Impact Factor. This groundbreaking research introduces a novel method for transforming crystalline phases into glasses through mechanochemical processes. This environmentally friendly and efficient method opens new doors for manufacturing glasses, revolutionising traditional processes. This remarkable research celebrates this extraordinary blend of chemistry, physics, and innovation!

Abstract

The first mechanochemically-induced hybrid organic-inorganic perovskites (HOIPs) crystal-to-glass transformation was reported as a quick, environmentally friendly, and productive method of making glasses. Within ten minutes of mechanical ball milling, the crystalline phase transformed into the amorphous phase, demonstrating glass transition behaviour as shown by thermal analysis methods. The microstructural evolution of amorphization was studied using time-resolved in situ ball-milling with synchrotron powder diffraction. The results indicated that energy may accumulate as crystal defects because the crystallite size reaches a comminution limit before the amorphization process is finished. The limited short-range order of amorphous HOIPs was discovered through total scattering experiments, and photoluminescence (PL) and ultraviolet-visible (UV-vis) spectroscopy were used to examine their optical characteristics.

Explanation of the research in layperson’s terms

Crystalline inorganic perovskites (general chemical formula is ABX3, where A and B are cations, and X is anion) are generally known for their unique optoelectronic applications, such as solar cells, photodetectors, and LEDs (light emitting diodes). In this research, Dr Das revealed hybrid materials comprised of organic linkers and inorganic nodes, which constitute hybrid organic-inorganic perovskites (HOIPs). The research demonstrated a rapid and environment-friendly (mechanochemically ball milling assisted) synthetic approach to transform the crystalline phase to its non-crystalline/amorphous phase. Interestingly, the amorphous phase of HOIPs showed temperature-dependent glass transition temperature (Tg) at very low temperatures, ~50 C. The structure of the HOIP glasses has been characterised through total-X-ray diffraction studies and pair-distribution functions. The crystalline and glassy HOIPs showed optical properties, which were studied by photoluminescence (PL) and ultraviolet-visible (UV-vis) spectroscopy.

chinmoy-research1

Figure 1. Single crystal structures of (A) (S-NEA)2PbBr4 and (B) (rac-NEA)2PbBr4. Pb, Br, C, N and H atoms are represented by purple, brown, pink, blue, and grey colours, respectively. (C) Schematic illustration of the microstructural evolution on 2D HOIPs upon ball-milling. (D) UV-Vis and (E) photoluminescent properties of crystalline (S-NEA)2PbBr4 (purple) and glassy (S-NEA)2PbBr4 (blue) HOIPs.

Practical implementation/ social implications of your research

Through the mechanochemical approach, we prepared novel hybrid organic-inorganic perovskite (HOIP) glasses within ten minutes, showing the greater feasibility of processing the glass material for industrial implication. On the other hand, we also demonstrated that the HOIP glasses showed photoluminescence properties, which would enable us to fabricate the device for solar cells, photodetectors, LEDs and many more.

Collaborations

  • Department of Materials Science and Metallurgy, University of Cambridge, United Kingdom.

The Department of Chemistry has established a research group at SRM University-AP, and the group has started to explore an emergent research area of crystal-glass composite materials towards the applications of atmospheric water harvesting, solid-state electrolytes, photovoltaics, and conversion of gaseous Carbon-dioxide molecules to industrially relevant liquids, such as methanol or ethanol.

Any interested candidate can reach out to Dr Chinmoy for exciting projects.

NMRIn a significant leap forward for scientific research, SRM University-AP proudly inaugurated the 400 MHz NMR (Nuclear Magnetic Resonance) Spectrometer, procured through the DST-FIST program. This acquisition is a vital component of the broader DST FIST project, which has been awarded to the Department of Chemistry at SRM University- AP with a budget of 2.20 crores.

As part of the project, the Department of Chemistry was recommended a 400 MHz NMR spectrometer by DST, which will play a crucial role in enhancing our expertise and aiding in achieving the proposed objectives. This state-of-the-art equipment is capable of characterising organic, inorganic, and biomolecules, enabling us to conduct comprehensive analyses and advance our understanding of complex chemical systems.

The ceremony, graced by esteemed guests, university dignitaries, faculties, and students, heralded a new era of scientific exploration and innovation. Prof. Lakshmi Kantam Mannepalli, Dr B P Godrej Distinguished Professor, ICT Mumbai, Chief Guest at the event, expressed, ” The inauguration of the 400 MHz NMR Spectrometer heralds a new era of precision and insight in scientific exploration. This instrument will unravel the mysteries of molecular structures and catalyse groundbreaking discoveries in the realm of chemistry and beyond.”

Dr S Mannathan, Associate Professor, Department of Chemistry, extended a warm welcome to the esteemed gathering and offered an insightful demonstration of the equipment’s operation, highlighting its advanced features and functionalities.

Prof. Manoj K Arora, Vice Chancellor, conveyed heartfelt congratulations to the team for this remarkable accomplishment, emphasising the transformative impact the new NMR Spectrometer will have on research and academic pursuits within the Department of Chemistry and beyond.”

Prof D Narayana Rao, Executive Director – Research, SRM Group of Institutions, emphasised, “The addition of this advanced equipment will significantly enhance the research capabilities, opening new avenues for exploration and discovery.”

V S Rao, Advisor, lauded the team for their achievement, stating, “This state-of-the-art equipment embodies our commitment to providing cutting-edge resources for our researchers and fostering a culture of innovation and discovery.”

Dr Pardha Saradhi Maram, Head of the Department of Chemistry, expressed his gratitude to all present and extended heartfelt thanks for their support and encouragement.

The acquisition of the 400 MHz NMR Spectrometer represents a significant advancement in scientific instrumentation, enabling researchers to delve deeper into molecular structures, chemical compositions, and dynamic processes. The Equipment will not only benefit the Department of Chemistry and Physics but also serve as a valuable resource for faculties and students across various disciplines.

The university has already trained 70 to 80 individuals in the operation of this equipment and is planning to organise a workshop for students and faculties from different universities, offering them the opportunity to leverage this advanced technology for their research and academic pursuits.

ETSST 1

The Department of Chemistry at SRM University-AP has taken a significant initiative by organising an International Conference on “Emerging Trends in Supramolecular Science and Technology” (ETSST-2024) on March 07 and 08, 2024. This two-day conference brought together some of the most renowned and accomplished national and international intellectuals in the field of chemistry, who will share their insights and expertise on the latest advancements, emerging trends, and future prospects in the domain of supramolecular science and technology. The conference promises to be a great platform for researchers, scientists, academicians, and students to exchange ideas, network, and collaborate towards making breakthrough contributions in the field.

The conference marked the presence of academic stalwarts from institutes of national and international repute who expounded on the relevance of the conference and discoursed upon the various topics.

The event also featured the unveiling of the abstract book compiled by the department. Vice Chancellor, Prof. Manoj K Arora; Registrar, Dr R Premkumar; the Associate Dean- Science, Prof. Jayaseelan Murugaiyan; Chairman and Convenor ETSST-2024, Prof. C Pulla Rao; HoD- Chemistry, Dr Pardha Saradhi Maram; Dr Seema Rani and Dr Balaji Babu, Assistant Professors, Department of Chemistry, SRM AP bore witness to this momentous occasion.

At its core, the essence of this conference lay in its audacious objective – to unravel the enigmatic world of supramolecular science, where chemistry transcends the boundaries of individual molecules. It is a domain where complexity breeds innovation, and practical applications pave the way for unprecedented advancements in engineering and technology.

As the curtains drew to a close on this grand spectacle, the echoes of inspiration and collaboration continued to reverberate within the hearts and minds of all who were part of this transformative experience. The bonds forged and the knowledge shared during ETSST-2024 will forever shape the trajectory of supramolecular science and technology.

 

ETSST

In a world of fast-escalating environmental challenges, the idea of sustainability comes as a ray of hope for a safe and sound future. The present scenario calls for the kind of development that meets the needs of the present without compromising the future. In this regard, the Department of Chemistry at SRM University-AP organised a colloquium, that aimed to provide students with a comprehensive understanding of the concepts of Green Chemistry.

Dr Ram Mohan, an expert in the field of Green Chemistry and a renowned academician at the Department of Chemistry, Illinois Wesleyan University, delivered a lecture on the topic “Better Living Through Green Chemistry: An Introduction to Toxic Molecules”. Dr Mohan spoke elaborately on the grave dangers of toxic molecules and their adverse effects on the environment and human health. He raised awareness about the critical role of green chemistry in reducing the usage of such harmful molecules and replacing them with environmentally safe alternatives.

Dr Mohan also conducted workshops on “Better Living Through Green Chemistry”, as a continuation of his lecture. During the workshop, he quoted several case studies that showcased the benefits of using environmentally safe processes and chemicals in industry. These case studies demonstrated how the practice of green chemistry can lead to the development of numerous Eco-friendly processes and chemicals that have greatly improved human life and reduced environmental impact.

The Department of Chemistry at SRM University-AP organised an academic colloquium called ChemZeal 2 on December 02, 2023. The event aimed to promote the Department and its research among undergraduate and graduate students from various colleges. It also provided a platform for students to interact with chemistry enthusiasts and learn about the latest advancements and research in the field.

ChemZeal 2 featured a lecture by academic stalwart, Prof. U V Varadaraju on Solid-State Materials in Chemistry from the Department of Chemistry, IIT Madras. Prof. Varadaraju also spoke about various aspects of the field, including research, career paths, higher studies, and job opportunities in the industry.

The welcome note was given by the Department Head, Dr Pardha Saradhi Maram, while Vice-Chancellor Prof. Manoj K Arora and Prof. Jayaseelan Murugaiyan, Associate Dean in-charge (Science), also addressed the gathering with their valuable inputs. The event also included an interactive session with the guest speaker, where faculty and students could interact and get expert insights.

ChemZeal 2 also featured a talent test for over 320+ students from different colleges, with prizes awarded to the top three winners. The event was designed to attract students to pursue higher education and research in the field of Chemistry and provided a platform for BSc/MSc/PhD students to showcase their research and interact with potential candidates.

The event organisers – Dr Sabyasachi Chakrabortty (Convenor) & Dr J P Raja Pandiyan (Co-convenor) helped culminate the outreach activity with a campus tour, where attendees could witness state-of-the-art facilities, high-end research labs, and futuristic technology.

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

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

Dr Rajapandiyan Paneerselvam from the Department of Chemistry has published a paper titled “Advances of surface-enhanced Raman and IR spectroscopies: from nano/microstructures to macro-optical design” in the journal Light: Science & Applications, Volume 10, Article number: 161 (2021) having an Impact factor of 17.7.

Raman and infrared (IR) spectroscopy are powerful analytical techniques, which are widely used for a variety of applications including food analysis, environmental analysis, chemical, and biomolecule analysis. This review article presents some latest advancements in vibrational spectroscopic techniques, and further developments in this field are given with emphasis on emerging techniques and methodologies.

This article has been published with Prof Zhong-Qun Tian’s group, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.

Furthermore, Dr Rajapandiyan’s research group will focus on the development of plasmonic nanostructures for surface-enhanced Raman spectroscopy and its applications in food science, spectroelectrochemistry, and microfluidics in the future.

Read the full paper here: https://doi.org/10.1038/s41377-021-00599-2

An interactive session between Prof U Ramamurty, President Chair Professor, School of Mechanical & Aerospace Engineering at Nanyang Technological University (NTU), Singapore, and the faculty members of SRM University – AP, Andhra-Pradesh was held on Monday.

During the discussion, Prof Ramamurty emphasized the importance of research collaboration between faculty members from different research areas and about utilizing expertise to achieve significant scientific output.

Dr Pardhasaradhi Maram from the Department of Chemistry, Dr Sabyasachi Mukhopadhyay from the Department of Physics, and Prof G S Vinod Kumar from the Department of Mechanical Engineering presented their detailed research areas that focus on storage devices, catalysts for value-added products, energy and sensing devices, novel metallic materials, additive manufacturing of metals and Bio-implants, and industry collaborative research work.

Prof Ramamurty said that he is glad to see that productive science is being done at SRM University-AP. “Given that the University has started only 4 years ago and been functioning amidst a pandemic for more than one and a half years, the progress in research is significant and very impressive. Interdisciplinary efforts between various departments in the University will give effective results”, he added.

Prof D Narayana Rao, Pro-Vice-Chancellor, SRM University – AP expressed his interest in establishing NTU – SRM joint Centre for Advanced Research in functional and structural materials at SRM University campus to Prof Ramamurty. The centre that Prof Rao envisions will provide an opportunity to synergize the expertise and resources of NTU, Singapore, and SRM University – AP to carry out front-line research in the areas of novel materials, self-healing materials and also additive manufacturing (3D Printing of metals and bio-implants).

Dr Nimai Mishra, Assistant Professor, Department of Chemistry, SRM University-AP, Andhra Pradesh, along with his research group comprising of students pursuing PhD under him, Ms V.G.Vasavi Dutt and Mr Syed Akhil has published a research article titled Cesium Lead Bromide Perovskite Nanocrystals as a Simple and Portable Spectrochemical Probe for Rapid Detection of Chlorides in the Journal ChemistrySelect (Publisher: Wiley-VCH on behalf of Chemistry Europe, Impact Factor-2.2).

Chloride anions are widely abundant in water and when they combine with calcium, potassium, and magnesium, they form chloride salts. However, the higher concentrations badly affect the environment by causing severe dehydration and even plant death. High concentrations of sodium chloride exhibit the potential of corrosive damage thereby releasing toxic metals from plumbing fixtures. Hence, there is a need to monitor the concentration levels of chloride salts in water. Several techniques like titration, spectrophotometry, ion chromatography, electrochemistry, etc have been reported to date. Despite the high accuracy and precision of these techniques, they involve expensive instrumentation and is out of reach from on-site detection. Hence, it is necessary to look for simple, portable, and cost-effective strategies for the detection of chlorides in the water.

In this article, Dr Mishra’s research group demonstrated that the wide spectral tunability of CsPbBr3 perovskite nanocrystals (NCs) via instantaneous and facile anion exchange, make them a suitable candidate for chloride detection. Rapid anion-exchange processes between CsPbBr3 perovskite NCs and different chloride solutions were carried out in ambient conditions. The resultant anion-exchanged CsPbCl3-xBrx NCs preserved the structural properties and exhibited a remarkable blue shift in photoluminescence spectra. This forms a basis for the detection of chloride ions in water. This has been applied with the limit of detection up to 100 µM. The detection strategies were not only limited to the direct addition of chloride solutions to NCs, but they also showed a visual colour change under UV light when the chloride solution is drop-casted on CsPbBr3 films that are deposited on glass substrates. Furthermore, the detection strategy is established by drop-casting CsPbBr3 NCs onto paper strips that are pre-soaked in chloride solutions. A considerable blue shift in fluorimetry proves them to be an excellent sensing medium as practical spectrochemical probes for on-site detection of chlorides. Based on this, a colour chart and selectivity chart to access the presence of chlorides and their concentration is also demonstrated.

Read the full paper here