Abhijit Patra

Indian Institute of Science Education and Research Bhopal | IISER · Department of Chemistry

Heterogeneous nanopore structure and distribution regulate the gas trapping, desorption kinetics, and diffusion in shale matrices. In shale, pores range from continuous micro- and mesopore size distributions, varying with organic (total organic matter-TOC) and inorganic constituents (clay content, Fe-bearing minerals, quartz, etc. ). Previous resea...

Surface contamination of materials by nitrogenous impurities is a major problem that can bias the quantification of ammonia in photocatalytic N2 fixation reactions. In this work, SrTiO3 nanocubes were prepared by using a nitrogenous precursor and engineered with Ti3+ sites and oxygen vacancy defects in a one-step solvothermal approach. It was obser...

The properties and functions of non-covalent interaction-driven fluorescent supramolecular self-assembly depend greatly on their evolution dynamics. Electron microscopy, atomic force microscopy, and confocal laser scanning microscopy have been used to elucidate the formation of molecular self-assembly. However, some pertinent issues, such as the dr...

Metal oxoanions adversely affect the food chain through bioaccumulation and biomagnification. Therefore, they are among the major freshwater contaminants that require immediate remediation. Although several adsorbents have been developed over the years for sequestering these micropollutants, the selective removal of oxoanions remains still a formid...

Dynamic covalent chemistry (DCC) opens up a fascinating route for the construction of well-organized supramolecular architectures, starting from organic molecular cages to crystalline macromolecular covalent organic frameworks (COFs). Herein, for the first time, we have manifested a facile room-temperature DCC-directed transformation of discrete or...

Dynamic covalent chemistry (DCC) opens up a fascinating route for the construction of well‐organized supramolecular architectures, starting from organic molecular cages to crystalline macromolecular covalent organic frameworks (COFs). Herein, for the first time, we have manifested a facile room‐temperature DCC‐directed transformation of discrete or...

A donor-acceptor-based soluble porous organic polymer (PzDBS) was fabricated using a flexible core composed of N,N’-octyl biphenothiazine and a rigid building unit involving dibenzothiophene dioxide. The soluble porous organic polymer...

Selective oxidation of C(sp3)-H bonds of aliphatic hydrocarbons to form value-added chemicals is still a challenging task being pursued. Herein, a p-n heterojunction based Ni3V2O8@g-CN (NVO@g-CN) nanocomposite as a visible...

Small strategic perturbations of the molecular structures impart significant variation in the evolution dynamics and properties of supramolecular self-assembled architectures. However, probing the in situ evolution dynamics of molecular assembly remains a challenge. Herein, we unraveled the real-time, early stage environment-sensitive dynamic molec...

Porous organic polymers (POPs) have received increasing attention due to their properties, such as permanent porosity with tunable pore size, robust structure, high surface area, and versatility of the backbone for the desired function. Such properties prove to be quite valuable for a plethora of sustainable applications. POPs can largely be classi...

Deciphering the dynamics of intracellular organelles has gained immense attention due to their subtle control over diverse, complex biological processes such as cellular metabolism, energy homeostasis, and autophagy. In this context, molecular materials, including small-organic fluorescent probes and their supramolecular self-assembled nano-/microa...

Catalysts play a pivotal role in achieving the global need for food and energy. In this context, porous organic polymers (POPs) with high surface area, robust architecture, tunable pore size, and chemical functionalities have emerged as promising testbeds for heterogeneous catalysis. Amorphous POPs having functionalized interconnected hierarchical...

A judicious structural modification of molecular building units imparts significant variation in the evolution dynamics of supramolecular self-assembled architectures and their functional properties. The incorporation of alkyl chains into the rigid and π-conjugated molecular backbone not only directs the self-assembly but also enhances the hydropho...

The development of luminescent probes has gained significant interest in real-time intracellular sensing and imaging of various biologically relevant species. The accuracy in sensing and imaging circumventing the background signals due to autofluorescence is essential to decipher subtle changes in cellular microenvironments under diverse pathophysi...

Unifying hydrogen (H2) fuel production with value-added chemicals from biomass through semiconductor-mediated solar redox reaction is an extremely appealing and sustainable process to uproot the energy and environmental issues, cooperatively...

An intriguing case of intramolecular and intervalence charge transfer-driven multistate electrochromism and electrofluorochromism in dibenzophenazin-(phenyl)methanone and arylamine-based redox-active donor-acceptor-donor molecules was elucidated. Tunable absorption from UV to NIR and on-off...

All-organic thermally activated delayed fluorescence (TADF) materials have emerged as potential candidates for optoelectronic devices and biomedical applications. However, the development of organic TADF probes with strong emission in the longer wavelength region (> 600 nm) remains a challenge. Strong π-conjugated rigid acceptor cores substituted w...

The electrochromic materials have received immense attention for the fabrication of smart optoelectronic devices. The alteration of the redox states of the electroactive functionalities results in the color change in response to electrochemical potential. Even though transition metal oxides, redox‐active small organic molecules, conducting polymers...

Tuning the fluorescence of π-conjugated small organic molecules through the structural modifications and in the presence of external stimuli have found immense applications ranging from sensing, switching, optoelectronics to bioimaging. Herein, we demonstrated a simple design strategy for the synthesis of a pyrene-cyanostyrene-pyridine molecular tr...

A π-conjugated porous organic polymer (BCzBz) was fabricated employing N,N'-bicarbazole and benzothiadiazole as molecular building units exhibiting broad visible light absorption. The photostable, water-dispersible, and cytocompatible BCzBz was demonstrated as...

We fabricated an inorganic-organic hybrid upconversion nanoprobe for the ratiometric detection of aliphatic biogenic amines in water. The hybrid nanoprobe comprises a thiophene-based acceptor-π-donor-π-acceptor organic fluorescent dye, TDPM, and near-infrared light-absorbing upconversion nanoparticles (UCNPs). The organic dye was loaded into a meso...

The advantages of the cage-to-network design strategy were demonstrated by knitting a waterwheel-like preporous molecular cage, noria, with a rigid aromatic linker to obtain a highly microporous organic polymer (NPOP, SBET: 748 ± 25 m2 g-1). The NPOP was employed for the catalytic conversion of CO2 to cyclic carbonates under solvent-free reaction c...

Heptazine‐based microporous polymeric network, HMP‐TAPA was synthesized via direct coupling of trichloroheptazine and tris(4‐aminophenyl)amine (TAPA). The high surface area of 424 m 2 /g was achieved which is the highest surface area among heptazine‐based polymeric networks (HMPs). The tailored electron‐donor and acceptor units in HMP‐TAPA render t...

Supramolecular self-assembly of small organic molecules has emerged as a powerful tool to construct well-defined micro- and nanoarchitecture through fine-tuning a range of intermolecular interactions. The size, shape, and optical properties of these nanostructures largely depend on the specific assembly of the molecular building units, temperature...

In an enduring quest to develop highly efficient display and lighting devices over the decades, semiconductor nanocrystals have recently emerged as favorable candidates. However, developing a prudent and viable methodology to fabricate high-quality semiconductor nanocrystals exhibiting tunable luminescence, including single-component white light em...

p>Nanoporous organic polymers with distinct morphologies are of immense interest for a broad spectrum of applications ranging from catalysis to molecular separation, energy storage, and energy conversion. However, developing facile and versatile methodologies to obtain well-orchestrated morphologies along with high specific surface area pertinent t...

Strategizing the exploitation of renewable solar light could undoubtedly provide new insight into the field of biomass valorization. Therefore, for the first time, we reported a heterogeneous photocatalytic oxidation route of renewable furfural (FUR) to produce industrial feedstocks maleic anhydride (MAN) and 5-hydroxy-2(5H)-furanone (HFO) under si...

Supramolecular self-assembly of small organic molecules has emerged as a powerful tool to construct well-defined micro- and nanoarchitecture through fine-tuning a range of intermolecular interactions. The size, shape, and optical properties of these nanostructures largely depend on the temperature and polarity of the medium, along with the specific...

Covalent organic frameworks (COFs) having layered architecture with open nanochannels and high specific surface area are promising candidates for energy storage. However, the low electrical conductivity of two‐dimensional COFs often limits their scope in energy storage applications. The conductivity of COFs can be enhanced through post‐synthetic mo...

Supramolecular cavitands and organic cages having a well-defined cavity and excellent host–guest complexing ability have been explored for a myriad of applications ranging from catalysis to molecular separation to drug delivery. On the other hand, porous organic polymers (POPs) having tunable porosity and a robust network structure have emerged as...

div> Covalent organic frameworks (COFs) with layered architecture with open nanochannels and high specific surface areas are promising candidates for energy storage. However, the low electrical conductivity of two-dimensional COFs often limits their scope in energy storage applications. The conductivity of COFs can be enhanced through post-synthet...

Controlling the nonradiative deactivation of triplet states and tuning the singlet-triplet energy gap are the major challenges to develop materials exhibiting thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP). Additionally, the conformational flexibility/ rigidity around the donor-acceptor bond and π-spacer...

Semiconductor nanocrystals are promising for display and lighting devices. Herein, we report a facile one-pot synthetic route to fabricate white light emitting CdSexSy nanocrystals with enhanced quantum yield using CdO, S powder, and Se powder as precursors. The phosphine-free route was adopted, employing paraffin oil as the reducing agent and solv...

Porous organic frameworks (POFs) with heteroatom rich ionic backbone have emerged as advanced materials for catalysis, molecular separation, and antimicrobial applications. The loading of metal ions further enhances Lewis acidity, augmenting the activity associated with such frameworks. Metal-loaded ionic POFs, however, often suffer from physicoche...

White light emitting (WLE) materials are of increasing interest owing to their promising applications in artificial lighting, display devices, molecular sensors, and switches. Typically, the three primary (red, green, and blue) or two complementary (e.g., yellow and blue or red and cyan) colored emissive units are combined to generate white light....

p> Control of nonradiative deactivation of triplet states and tuning the singlet-triplet energy gap (ΔE_ST) are the major challenges to develop materials exhibiting thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP). Herein, we propose a new class of multichromophoric tridonor-acceptor (D<sub>3</su...

White light emitting (WLE) materials are of increasing interest owing to their promising applications in artificial lighting, display devices, molecular sensors, and switches. In this context, the organic WLE materials cater to the interest of the scientific community due to their promising features like color purity, long‐term stability, solution...

Porous organic frameworks (POFs) with heteroatom rich ionic backbone have emerged as advanced materials for catalysis, charge-specific molecular separation and antibacterial activity. The loading of metal ions further enhances Lewis acidity augmenting the activity associated with the frameworks. Metal-loaded ionic POFs however often suffer from phy...

The current study demonstrates a simple and economical synthetic approach for the development of a multifunctional Schiff base compound (NRSB) through the condensation reaction between 2-hydroxynapthaldehyde and a five-membered heterocycle...

Macrocyclic cavitands having aesthetically appealing architecture and excellent host-guest complexation ability exhibit a broad range of applications from molecular separation, catalysis, sensing to drug delivery. However, the close packing of the zero-dimensional (0D) porous cavitands reduces their activity in the solid state. Knitting the macrocy...

N-rich all-organic cages remain unexplored for CO2 fixation. Herein, the shape-persistent amine/imine cages were employed for the metal-free, cycloaddition of CO2 with epoxide to cyclic organic carbonates under solvent-free reaction...

The switching between delayed fluorescence and phosphorescence of purely organic molecules via triplet harvesting is one of the key designs for high-performance optoelectronic devices. However, the ultrafast deactivation of triplet states limits their efficiencies.1,2 The longer component emission with high quantum efficiency can be apprehended by...

Taking C -phenylresorcin[4]arene (RN4) as a model building block, we fabricated a series of porous organic polymers (POPs: RN4-OH, RN4-Az-OH, and RN4-F) where the surface area was enhanced up to ~8 folds (1229 m²g^-1) than that of the pristine cavitand (156 m²g^-1). The advantage of connecting the 0D poro...

Organic chromophores consisting of well-separated electron donor (D) and electron acceptor (A) units connected through the π-linkers attract the attention over the last few years owing to their rich photophysical properties and applications in optoelectronic devices. The fundamental phenomenon of intramolecular charge transfer (ICT) from the donor...

Organic push-pull chromophores, in which electron donor (D) and electron acceptor (A) units are connected through π-linkers have been extensively studied because of their rich photophysical properties and potential applications in optoelectronic materials and devices.1 The most fundamental phenomenon governing the interesting optical properties of...

The present study demonstrates the tuning of iconic optical features of pyrene through its judicious assembly with C3-symmetric triaminoguanidinium ion leading to the development of a unique multifunctional luminescent material, PYTG. The fine tuning of the concentration and the presence of external stimuli like temperature, the addition of analyte...

A novel approach for the fabrication of a solution processable conjugated porous organic polymer (CzBDP) involving a flexible core comprised of carbazole and boron dipyrromethene was developed. The red emitting...

A novel class of pyrene-based conjugated porous organic polymers having N-containing network was developed employing Buchwald–Hartwig coupling for supercapacitor energy storage. The pristine polymer was found to exhibit the specific...

A novel class of pyrene-based conjugated porous organic polymers having N-containing network was developed employing Buchwald– Hartwig coupling for supercapacitor energy storage. The pristine polymer was found to exhibit the specific capacitance of 456 F g-1 at 0.5 A g-1 current density with excellent long-term cyclic stability

The intramolecular charge transfer-driven emission properties of T and V-shaped donor-acceptor-donor molecules involving new acceptor core of pyridoquinoxaline were demonstrated. The T-shaped molecule exhibits large Stokes shift, red emission in...

A simple and cost-effective methodology employing environmentally benign substances for the fabrication of white-light emitting materials is important for practical applications in the field of lighting and display devices. Designing of purely organic-based white-light emitting system with high quantum efficiency in the aqueous medium is an unmet c...

A new core of [1,2,5]-thiadiazolo-[3,4-c]-pyridine was employed for the fabrication of microporous organic polymers exhibiting a very high CO2 uptake of 5.8 mmol g-1 (25.5 wt%) at 273 K and...

What a PITE! A multifunctional fluorescent bioprobe based on pyridoindole (PI) and tetraphenylethylene (TE), PITE, showing pH-responsive fluorescence switching in solution, as nanoparticles and in the solid state that can be used to sense toxic organic acid vapor is presented. Hydrophobic nanoparticles of PITE turned out to be highly specific for t...

A versatile fluorescent probe, PITE, based on alkyl substituted pyridoindole (PI) and tetraphenylethylene (TE) exhibiting facile pH-induced fluorescence switching in solution, nanoparticles and solid state is presented. Strong fluorescence in the solid state besides solution and aggregated state allow sensing of toxic acid vapor. Fluorescence "off-...

A series of porous organic polymers (POPs) were fabricated based on the boron dipyrromethene (BODIPY) core. The variation of the substituents in the BODIPY core and the fine tuning of the Sonogashira polycondenzation reaction with 1,3,5-triethynylbenzene led to the formation of POPs with a wide range of surface area and porosity. A tenfold increase...

Schiff base condensation and C–C coupling between a biologically important heterocycle pyridoij1,2-a]indole (PI) and aggregation induced emission active tetraphenylethylene (TE) led to the formation of weakly fluorescent PITE1 and strongly fluorescent PITE2, respectively. The photophysical phenomenon was rationalized by crystal structure analysis; P...

A solution processable conjugated porous organic polymer (POP) based on tetraphenyl-5,5-dioctylcyclopentadiene (TPDC-DB) was employed for nitroaromatic sensing by amplified fluorescence quenching. A comprehensive investigation was carried out using a set of 30 closely related analytes such as nitrophenols, nitrotoluenes, nitroanilines, nitobenzenes...

A tetraphenylcyclopentadiene based multifunctional, solution processable, fluorescent, ultramicroporous polymer exhibiting high hydrogen uptake was employed for encapsulation of dyes to obtain enhanced white light emission in solution, nanoparticles, gel and transparent thin film. Hybrid nanoparticles showed a quantum yield of 35% with a high color...

Conjugated polymer nanoparticles based on poly[9,9-bis(2-ethylhexyl)fluorene] and poly[N-(2,4,6-trimethylphenyl)-N,N-diphenylamine)-4,4'-diyl] are fabricated using anionic surfactant sodium dodecylsulphate in water by miniemulsion technique. Average diameters of polyfluorene and polytriarylamine nanoparticles range from 70 to 100 and 100 to 140 nm,...

Conjugated porous organic polymers based on novel core of tetraphenyl-5,5-dioctylcyclopentadiene (TPDC) have been fabricated in the form of powder (P1), soluble in common organic solvents (P2) as well as aqueous dispersion of nanoparticles (P3). Fine tuning of the conditions of polycondensation reactions involving tetrakis(4-bromophenyl)-5,5-diocty...

Conjugated porous organic polymers based on novel core of tetraphenyl-5,5-dioctylcyclopentadiene (TPDC) have been fabricated in the form of powder (P1), soluble in common organic solvents (P2) as well as aqueous dispersion of nanoparticles (P3). Fine tuning of the conditions of polycondensation reactions involving tetrakis(4-bromophenyl)-5,5-diocty...

A simple one-pot protocol for the Pd-catalyzed oxidative annulation of internal alkynes with indoles to form pyridooxindole derivatives is presented.

We describe a straightforward strategy for the synthesis of strongly fluorescent pyridoindoles by Pd-catalyzed oxidative annulations of internal alkynes with C-3 functionalized indoles through CH/NH bond activation in a one-pot tandem process. Mechanistic investigations reveal the preferential activation of NH indole followed by CH activation durin...

The conformational equilibrium and thermodynamic parameters of cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethene (1a) and its trans derivative 1c are presented. Irradiation of both compounds was carried out by using 365 nm light, which affects the cis/trans isomerisation process, whereas irradiation with 405 nm light preferentially promotes...

Fluorescent microporous organic polymers (MOPs) are an emerging class of porous organic materials with considerable technological relevance due to great promise in a range of applications, in addition to typical usage in gas storage and catalysis. In this respect, innovative optical materials have been developed based on MOPs. In this Concept artic...

An ultra-bright fluorescence probe comprising conjugated polymer nanoparticles is developed for biological imaging. Highly blue fluorescent polyfluorene nanoparticles (PF-NPs) stabilized by sodium dodecylsulfate with an average diameter of 100 nm are prepared by a miniemulsion technique. A folate-conjugated cationic triblock copolymer is employed t...

A convenient protocol has been developed to fabricate one-dimensional nanostructures of a photochromic molecule cis-l,2-dicyano-l,2-bis(2,4,5-trimethyl-3-thieny1)ethene (CMTE). Light-induced self-assembled nanorods and nanowires of the colored form were obtained in situ under UV light irradiation in aqueous dispersion and redissolved under green li...

Novel dye-terminated, hyperbranched polytruxenes and polytruxene-block-polythiophene multiblock copolymers have been synthesized in a simple "AB(2) + A" approach. Photoexcitation into the higher energy polytruxene absorption band results in an efficient excitation energy transfer to the peripheral dye or polythiophene blocks.