BISWAJIT MONDAL
Verified @gmail.com
Postdoctoral scholar
KIT, Germany
RESEARCH INTERESTS
2D materials, Water purification
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Debasmita Ghosh, Mohd Azhardin Ganayee, Anirban Som, Pillalamarri Srikrishnarka, Nidhi Murali, Sandeep Bose, Amrita Chakraborty, Biswajit Mondal, Pijush Ghosh, and Thalappil Pradeep
American Chemical Society (ACS)
We demonstrate the formation of a versatile luminescent organo-inorganic layered hybrid material, composed of bovine serum albumin (BSA)-protected Au30 clusters and aminoclay sheets. X-ray diffraction revealed the intercalation of Au30@BSA in the layered superstructure of aminoclay sheets. Coulombic attraction of the clusters and the clay initiates the interaction, and the appropriate size of the clusters allowed them to intercalate within the lamellar aminoclay galleries. Electron microscopy measurements confirmed the hierarchical structure of the material and also showed the cluster-attached clay sheets. Zeta potential measurement and dynamic light scattering probed the gradual formation of the ordered aggregates in solution. The hybrid material could be stretched up to 300% without fracture. The emergence of a new peak in the luminescence spectrum was observed during the course of mechanical stretching. This peak increased in intensity gradually with the degree of elongation or strain of the material. A mechanochromic luminescence response was further demonstrated with a writing experiment on a luminescent mat of the material, made by electrospinning.
Pallab Basuri, Sourav Kanti Jana, Biswajit Mondal, Tripti Ahuja, Keerthana Unni, Md Rabiul Islam, Subhashree Das, Jaydeb Chakrabarti, and Thalappil Pradeep
American Chemical Society (ACS)
Generation of current or potential at nanostructures using appropriate stimuli is one of the futuristic methods of energy generation. We developed an ambient soft ionization method for mass spectrometry using 2D-MoS2, termed streaming ionization, which eliminates the use of traditional energy sources needed for ion formation. The ionic dissociation-induced electrokinetic effect at the liquid-solid interface is the reason for energy generation. We report the highest figure of merit of current generation of 1.3 A/m2 by flowing protic solvents at 22 μL/min over a 1 × 1 mm2 surface coated with 2D-MoS2, which is adequate to produce continuous ionization of an array of analytes, making mass spectrometry possible. Weakly bound ion clusters and uric acid in urine have been detected. Further, the methodology was used as a self-energized breath alcohol sensor capable of detecting 3% alcohol in the breath.
Biswajit Mondal, Samir Chattopadhyay, Subal Dey, Atif Mahammed, Kaustuv Mittra, Atanu Rana, Zeev Gross, and Abhishek Dey
American Chemical Society (ACS)
Considering the importance of water splitting as the best solution for clean and renewable energy, the worldwide efforts for development of increasingly active molecular water oxidation catalysts must be accompanied by studies that focus on elucidating the mode of actions and catalytic pathways. One crucial challenge remains the elucidation of the factors that determine the selectivity of water oxidation by the desired 4e-/4H+ pathway that leads to O2 rather than by 2e-/2H+ to H2O2. We now show that water oxidation with the cobalt-corrole CoBr8 as electrocatalyst affords H2O2 as the main product in homogeneous solutions, while heterogeneous water oxidation by the same catalyst leads exclusively to oxygen. Experimental and computation-based investigations of the species formed during the process uncover the formation of a Co(III)-superoxide intermediate and its preceding high-valent Co-oxyl complex. The competition between the base-catalyzed hydrolysis of Co(III)-hydroperoxide [Co(III)-OOH]- to release H2O2 and the electrochemical oxidation of the same to release O2 via [Co(III)-O2•]- is identified as the key step determining the selectivity of water oxidation.
Yu-Heng Wang, Biswajit Mondal, and Shannon S. Stahl
American Chemical Society (ACS)
Homogeneous ORR catalyzed by cobalt macrocycles typically leads to selective 2e/2H+ reduction of O2 to H2O2; however, variations in the reaction conditions make it difficult to compare the performa...
Abhijit Nag, Papri Chakraborty, Athira Thacharon, Ganesan Paramasivam, Biswajit Mondal, Mohammad Bodiuzzaman, and Thalappil Pradeep
American Chemical Society (ACS)
We present an example of host-guest complexes of atomically precise noble metal nanoparticles with cucurbit[7]uril (CB) in water, specifically concentrating on Ag29(LA)12 (where LA is α-lipoic acid...
Mohd Azhardin Ganayee, C. K. Manju, Wakeel Ahmed Dar, Biswajt Mondal, and Thalappil Pradeep
American Chemical Society (ACS)
In this article, a unique covalently linked aminoclay substrate, grafted with β-cyclodextrin (AC-CD), was prepared to entrap luminescent silver nanoclusters. Chemically synthesized aminoclay (AC) s...
Papri Chakraborty, Abhijit Nag, Biswajit Mondal, Esma Khatun, Ganesan Paramasivam, and Thalappil Pradeep
American Chemical Society (ACS)
We report fullerene (C60 and C70)-induced aggregation of atomically precise clusters, taking M25(SR)18– (M = Ag, Au and −SR is a thiolate ligand) clusters as an example. We show that dimers, trimer...
Abhijit Nag, Ananya Baksi, Jyotirmoy Ghosh, Vishal Kumar, Soumabha Bag, Biswajit Mondal, Tripti Ahuja, and Thalappil Pradeep
American Chemical Society (ACS)
Polytetrafluoroethylene (PTFE) is probably the most extensively used chemically inert and thermally stable polymer. We report the degradation of PTFE in water in the presence of common metals and c...
Yu-Heng Wang, Patrick E. Schneider, Zachary K. Goldsmith, Biswajit Mondal, Sharon Hammes-Schiffer, and Shannon S. Stahl
American Chemical Society (ACS)
The selective reduction of O2, typically with the goal of forming H2O, represents a long-standing challenge in the field of catalysis. Macrocyclic transition-metal complexes, and cobalt porphyrins in particular, have been the focus of extensive study as catalysts for this reaction. Here, we show that the mononuclear Co-tetraarylporphyrin complex, Co(porOMe) (porOMe = meso-tetra(4-methoxyphenyl)porphyrin), catalyzes either 2e–/2H+ or 4e–/4H+ reduction of O2 with high selectivity simply by changing the identity of the Brønsted acid in dimethylformamide (DMF). The thermodynamic potentials for O2 reduction to H2O2 or H2O in DMF are determined and exhibit a Nernstian dependence on the acid pKa, while the CoIII/II redox potential is independent of the acid pKa. The reaction product, H2O or H2O2, is defined by the relationship between the thermodynamic potential for O2 reduction to H2O2 and the CoIII/II redox potential: selective H2O2 formation is observed when the CoIII/II potential is below the O2/H2O2 potential, while H2O formation is observed when the CoIII/II potential is above the O2/H2O2 potential. Mechanistic studies reveal that the reactions generating H2O2 and H2O exhibit different rate laws and catalyst resting states, and these differences are manifested as different slopes in linear free energy correlations between the log(rate) versus pKa and log(rate) versus effective overpotential for the reactions. This work shows how scaling relationships may be used to control product selectivity, and it provides a mechanistic basis for the pursuit of molecular catalysts that achieve low overpotential reduction of O2 to H2O.
Biswajit Mondal, Pritha Sen, Atanu Rana, Dibyajyoti Saha, Purusottom Das, and Abhishek Dey
American Chemical Society (ACS)
Reduction of CO2 to value-added chemicals is a logical way of fixing the rising levels of CO2. Activation and reduction of CO2 requires low-valent transition metals as catalysts. A major challenge in this chemistry is sensitivity of these low-valent metal sites to more abundant O2. Since O2 is a stronger oxidant than CO2 and isolated from the obvious competitive inhibition of CO2, partial reduction of O2 leads to formation of reactive oxygen species like O2– and H2O2, which are deleterious to the catalyst itself. An iron porphyrin complex appended with four ferrocene groups in its distal site is demonstrated to reduce CO2 unabated in the presence of O2 as it can reduce O2 to benign H2O under the same conditions. Further investigations reveal that iron porphyrins, in general, reduce CO2 selectively in the presence of O2. The aforementioned selectivity is derived from a 500 times faster rate of reaction of CO2 with Fe(0) porphyrin relative to O2 despite a higher driving force for the latter.
Pritha Sen, Biswajit Mondal, Dibyajyoti Saha, Atanu Rana, and Abhishek Dey
Royal Society of Chemistry (RSC)
A series of iron porphyrins that vary only in the distal H-bonding network exhibit turnover frequencies (TOFs) ranging from 1.0 s−1 to 103 s−1.
Arijit Jana, Sourav Kanti Jana, Depanjan Sarkar, Tripti Ahuja, Pallab Basuri, Biswajit Mondal, Sandeep Bose, Jyotirmoy Ghosh, and Thalappil Pradeep
Royal Society of Chemistry (RSC)
A new and simple electrospray deposition to induce ambient phase transition in copper sulphide nanostructures.
Atanu Rana, Pradip Kumar Das, Biswajit Mondal, Subal Dey, Danielle Crouthers, and Abhishek Dey
Wiley
Sandeep Bose, Mohd. Azhardin Ganayee, Biswajit Mondal, Avijit Baidya, Sudhakar Chennu, Jyoti Sarita Mohanty, and Thalappil Pradeep
American Chemical Society (ACS)
Silicon nanoparticles (Si NPs) exhibiting observable luminescence have many electronic, optical, and biological applications. Owing to reduced toxicity, they can be used as cheap and environmentally friendly alternatives for cadmium containing quantum dots, organic dyes, and rare earth-based expensive phosphors. Here, we report an inexpensive silicon precursor, namely rice husk, which has been employed for the synthesis of Si NPs by rapid microwave heating. The Si NPs of ∼4.9 nm diameter exhibit observable green luminescence with a quantum yield of ∼60%. They show robust storage stability and photostability and have constant luminescence during long-term UV irradiation extending over 48 h, in contrast to other luminescent materials such as quantum dots and organic dyes which quenched their emission over this time window. Green luminescent Si NPs upon mixing with synthesized red and blue luminescent Si NP species are shown to be useful for energy-efficient white light production. The resulting white light ...
Biswajit Mondal, Ananthu Mahendranath, Anirban Som, Sandeep Bose, Tripti Ahuja, Avula Anil Kumar, Jyotirmoy Ghosh, and Thalappil Pradeep
Royal Society of Chemistry (RSC)
The reactivity of MoS2 NSs with lead ions (Pb2+ and Pb4+) in solution, leading to the same product with different morphologies, is reported.
Ananya Baksi, M. S. Bootharaju, Pratap K. Chhotaray, Papri Chakraborty, Biswajit Mondal, Shridevi Bhat, Ramesh Gardas, and Thalappil Pradeep
American Chemical Society (ACS)
Reactivity of monolayer protected atomically precise clusters of noble metals is of significant research interest. To date very few experimental data are available on the reaction thermodynamics of such clusters. Here we report a calorimetric study of the reaction of glutathione (GSH) protected silver clusters in the presence of excess ligand, GSH, using isothermal titration calorimetry (ITC). We have studied Ag11(SG)7 and Ag32(SG)19 clusters and compared their reactivity with GSH protected silver nanoparticles (AgNPs) and silver ions. Clusters show intermediate reactivity toward excess ligand compared to nanoparticles and silver ions. Several control experiments were performed to understand the degradation mechanism of these silver clusters and nanoparticles. The effect of dissolved oxygen in the degradation process was studied in detail, and it was found that it did not have a significant role, although alternate pathways of degradation with the involvement of oxygen cannot be ruled out. Direct confirma...
Sudipta Chatterjee, Kushal Sengupta, Biswajit Mondal, Subal Dey, and Abhishek Dey
American Chemical Society (ACS)
Reactivity as well as selectivity are crucial in the activation and electrocatalytic reduction of molecular oxygen. Recent developments in the understanding of the mechanism of electrocatalytic O2 reduction by iron porphyrin complexes in situ using surface enhanced resonance Raman spectroscopy coupled to rotating disc electrochemistry (SERRS-RDE) in conjunction with H/D isotope effects on electrocatalytic current reveals that the rate of O2 reduction, ∼104 to 105 M-1 s-1 for simple iron porphyrins, is limited by the rate of O-O bond cleavage of an intermediate ferric peroxide species (FeIII-OOH). SERRS-RDE probes the system in operando when it is under steady state such that any intermediate species that has a greater rate of formation relative to its rate of decay, including the rate determining species, would accumulate and can be identified. This technique is particularly well suited to investigate iron porphyrin electrocatalysts as the intense symmetric ligand vibrations allow determination of the oxidation and spin states of the bound iron with high fidelity. The rate of O2 reduction could be tuned up by 3 orders of magnitude by incorporating residues in the catalyst design that can exert "push" or "pull" effects, that is, axial phenolate and thiolate ligands and distal arginine residues. Similarly the rate of O-O bond cleavage can be enhanced by several orders of magnitude upon incorporating a distal Cu site and installing the active site in a hydrophobic protein environment in synthetic models and biosynthetic protein scaffolds. The selectivity, however, is solely determined by the site of protonation of a ferric peroxide (FeIII-OOH) intermediate and can be governed by installing preorganized second sphere residues in the distal pocket. The 4e-/4H+ reduction of O2 entails protonation of the distal oxygen of the FeIII-OOH species, while 2e-/2H+ reduction requires the proximal oxygen to be protonated. Mechanistic investigations of CO2 reduction by iron porphyrins reveal that the rate-determining step is the C-O bond cleavage of a FeII-COOH species analogous to the O-O bond cleavage step of a FeIII-OOH species in O2 reduction. The selectivity, resulting in either CO or HCOOH, is determined by the site of protonation of this species. These similarities suggests that the chemical principles governing the rate and selectivity of reduction of small molecules like O2, CO2, NOx, and SOx may be quite similar in nature.
Esma Khatun, Atanu Ghosh, Debasmita Ghosh, Papri Chakraborty, Abhijit Nag, Biswajit Mondal, Sudhakar Chennu, and Thalappil Pradeep
Royal Society of Chemistry (RSC)
We report the synthesis of a new silver cluster, [Ag59(2,5-DCBT)32]3- (I) (2,5-DCBT: 2,5-dichlorobenzenethiol), which acts as a precursor for the synthesis of three well-known silver clusters, [Ag44(2,4-DCBT/4-FTP)30]4- (II) (4-FTP: 4-fluorothiophenol and 2,4-DCBT: 2,4-dichlorobenzenethiol), [Ag25(2,4-DMBT)18]- (III) (2,4-DMBT: 2,4-dimethylbenzenethiol) and [Ag29(1,3-BDT)12(PPh3)4]3- (IV) (1,3-BDT: 1,3-benzenedithiol and PPh3: triphenylphosphine). This newly synthesized silver cluster, I, is characterized using UV-vis absorption studies, high resolution electrospray ionization mass spectrometry (ESI MS) and other analytical tools. The optical absorption spectrum shows distinct features which are completely different from the previously reported silver clusters. We perform the rapid transformations of I to other well-known clusters II, III and IV by reaction with different thiols. The time-dependent UV-vis and ESI MS measurements reveal that I dissociates into distinct thiolate entities in the presence of thiols and the thiolates recombine to produce different clusters. The conversion mechanism is found to be quite different from the previous reports where it occurs through the initial formation of ligand exchanged products. Here, we also show the synthesis of a different cluster core, [Ag44(2,4-DCBT)30]4- (IIa) using 2,4-DCBT, a structural isomer of 2,5-DCBT under the same synthetic conditions used for I. This observation demonstrates the effect of isomeric thiols on controlling the size of silver clusters. The conversion of one cluster to several other clusters under ambient conditions and the effect of ligand structure in silver cluster synthesis give new insights into the cluster chemistry.
Ananya Baksi, Atanu Ghosh, Sathish Kumar Mudedla, Papri Chakraborty, Shridevi Bhat, Biswajit Mondal, K. R. Krishnadas, Venkatesan Subramanian, and Thalappil Pradeep
American Chemical Society (ACS)
Experimental evidence for the existence of gas phase isomers in monolayer protected noble metal clusters is presented, taking Ag44(SR)30 (SR = 4-fluorothiophenol, p-mercaptobenzoic acid) and Ag29(BDT)12 (BDT: benzene dithiol) clusters as examples which do not show any isomeric structures in their crystals. Electrospray ionization coupled with ion mobility separation allowed for the identification of multiple isomers of Ag44SR30 cluster in its 3– and 4– charge states, their most abundant gas phase ions. Ag29(BDT)12 showed isomerism in its common 3– charge state. Isomerism is likely to be due to different types of ligand orientations in the staples leading to changes in the overall size and shape of the cluster ions, which was further confirmed by density functional theory calculations on Ag44(FTP)304–. No isomers were seen in the ions of the well-known cluster, Au25SR18 (SR = phenylethanethiol, dodecanethiol, and butanethiol).
Atanu Rana, Biswajit Mondal, Pritha Sen, Subal Dey, and Abhishek Dey
American Chemical Society (ACS)
Iron porphyrin complexes with second-sphere distal triazole residues show a hydrogen evolution reaction (HER) catalyzed by the Fe(I) state in both organic and aqueous media, whereas an analogous iron porphyrin complex without the distal residues catalyzes the HER in the formal Fe(0) state. This activation of the Fe(I) state by the second-sphere residues lowers the overpotential of the HER by these iron porphyrin complexes by 50%. Experimental data and theoretical calculations indicate that the distal triazole residues, once protonated, enhance the proton affinity of the iron center via formation of a dihydrogen bond with an Fe(III)-H- intermediate.
Subal Dey, Biswajit Mondal, Sudipta Chatterjee, Atanu Rana, Sk Amanullah, and Abhishek Dey
Springer Science and Business Media LLC
The past decade has seen considerable growth in the development of materials for fuel cell electrodes, and there is a desire for active electrocatalysts derived from base metals instead of noble metals. Fuels cells that consume H2 and O2 require catalysts to cleave these reactants, with the oxygen reduction reaction (ORR) — either 4H+/4e− reduction to 2H2O or 2H+/2e− reduction to H2O2 — being particularly challenging. The ORR is efficiently performed by certain metalloenzymes, and understanding the links between their structure and function aids the design of molecular ORR electrocatalysts. These bio-inspired catalysts exhibit good activity relative to previous synthetic systems and, furthermore, have provided mechanistic insights relevant to synthetic and enzymatic catalysts. This Review covers recent developments in homogeneous and heterogeneous molecular ORR catalysis, placing emphasis on reaction mechanisms and the factors governing rates and selectivities. Electrocatalysts for the oxygen reduction reaction are important components of energy technologies such as fuel cells. The study of molecular catalysts affords mechanistic insights that further the development of robust, active and energy-efficient systems. This Review describes state-of-the-art metal complexes that operate either in solution or immobilized on an electrode.
Partha Halder, Santanu Ghorai, Sridhar Banerjee, Biswajit Mondal, and Atanu Rana
Royal Society of Chemistry (RSC)
The present work presents a structural and functional model of rubredoxin and emphasizes the effect of the secondary coordination sphere on the redox potential.
Md Estak Ahmed, Subal Dey, Biswajit Mondal, and Abhishek Dey
Royal Society of Chemistry (RSC)
A Fe–Fe hydrogenase model is covalently attached to graphite electrodes using a modular approach.
Biswajit Mondal and Abhishek Dey
Royal Society of Chemistry (RSC)
Obtaining abundant pure hydrogen by reduction of water has an important implication in the development of clean and renewable energy.
Anamika Banerjee, Biswajit Mondal, Anuradha Verma, Vibha R. Satsangi, Rohit Shrivastav, Abhishek Dey, and Sahab Dass
Elsevier BV
Abstract Fe2O3 is known to offer an encouraging approach to sustainable solar energy harvesting. However, fast charge recombination caused by short diffusion length and inefficient charge separation after photon absorption restrict its wide application. In our present work, attempts have been made to enhance the efficiency of Fe2O3 thin films by combatting the aforesaid problems by initially doping the samples with titanium, followed by fabrication of an efficient and robust cobalt acetate (Co-Ac) water oxidation catalyst. FE-SEM, EDAX, AFM, and Raman analysis for modified photoelectrodeposited catalyst samples, along with comparative electrochemical and photoelectrochemical studies (Nyquist studies, Tafel plots, Voc decay rate), were conducted in two different pH media (phosphate buffer, pH 8 and pH 12.5) to highlight the enhanced efficiency of the thus prepared modified photoanodes. Modified photoanode (Co-Ac/Ti–Fe2O3) systems yielded higher photocurrent density than pristine samples (Ti–Fe2O3). Photocurrent densities under one sun illumination were found to be up to 225% higher in pH 12.5 and about 190.5% higher in pH 8 buffering medium than pristine doped samples at 0.85 V/SCE. Maximum photocatalytic activity is observed for 40 cycles of deposition of the catalyst, which is due to the extended lifetime of charge carriers of the photoelectrode, which has been experimentally verified by carrier lifetime estimation (with respect to Voc decay) in addition to minimum charge transfer resistance. Enhanced efficiency has been reported in terms of applied bias photon to current efficiency (ABPE), incident photon to current efficiency (IPCE), and Faradaic efficiency, along with turnover frequency, to support the high photocatalytic competence of the modified photoanode system for efficient water splitting and hydrogen generation.