Search

Cancer, one of the deadliest diseases for both sexes, has always demanded updated treatment strategies with time. Breast cancer is responsible for the highest mortality rate among females worldwide and requires treatment with advanced regimens due to the higher probability of breast cancer cells to develop drug cytotoxicity followed by resistance. Covalent organic framework (COF) materials with ordered nanoscale porosity can serve as drug delivery vehicles due to their biocompatible nature and large internal void spaces. In this research work, we have employed a novel biocompatible COF, TRIPTA, as a drug delivery carrier towards breast cancer cells. It served as a drug delivery vehicle for cisplatin in triple negative breast cancer (TNBC) cells. We have checked the potency of TRIPTA in combating the proliferation of metastatic TNBC cells. Our results revealed that cisplatin loaded over TRIPTA-COF exhibited a greater impact on the CD44

This review highlights the challenges and scope of the electrodeposited copper foam nanoarchitecture and its unique properties for various energy applications.

The development of an efficient and robust material for adsorptive removal of highly toxic metals like mercury from water resources is very challenging from the perspectives of hygiene and sustainable environment. Heteroatoms such as sulfur and nitrogen in this high surface area porous organic polymer is very promising for mercury remediation because it offers strong interactions between Hg(II) ions and S/N bound at the pore surface of the adsorbent. Thus, herein we developed a new secondary amine-linked, sulfur-containing and N-rich porous organic polymer, TTP-1, via polycondensation of a tetrapodal amine and thiophene-2-carbaldehyde. TTP-1 displayed a high BET surface area of 1034 m2 g−1 with hierarchical porosity and exceptionally high uptakes of 3106 and 691 mg g−1 for inorganic Hg2+ and organic methylmercury (CH3Hg+), respectively. The high adsorption efficiency for mercury capture is also supported from the strong noncovalent interaction of the ligand S and N lone pairs with Hg2+, as revealed from the ab initio quantum chemical calculation and AIM analysis. Cost-effective, eco-friendly and scaleable synthesis of porous organic polymer with hierarchical porosity reported herein may contribute to the design of a benchmark adsorbent for the remediation of mercury (Hg(II)/CH3Hg+) and may significantly aid in industrial and environmental cleanup.

Metal–organic frameworks (MOFs) containing multiple carboxylate and sulfonate linkers together with positively charged rare earth metals can offer new opportunities in heterogeneous catalysis. The high efficiency of the CO2 fixation reaction at low temperature and pressure over MOF-based catalysts is very challenging as it involves the renewable feedstock CO2 as a C1 source for the synthesis of value-added fine chemicals. Here we develop a new microporous La(III) based MOF through the solvothermal reaction using 5-sulfoisophthalic acid as the ligand, and the resulting La-5-SIP-MOF showed a high catalytic activity for the synthesis of cyclic carbonates from epoxides through the CO2 fixation reaction at room temperature and moderate (3–5 MPa) pressure. The optimum product yield was obtained in only 1 h reaction with the desired yield up to 98%. The La-5-SIP-MOF was characterized by using different analytical techniques such as single crystal X-ray diffraction, FTIR, PXRD, N2 adsorption/desorption study, UHR-TEM, solid UV-vis spectroscopy and TGA. The recycling efficiency and the structural stability of this MOF catalyst is also very high, suggesting a sustainable future of this La-MOF in heterogeneous catalysis.

Activation of C-H bonds of the hydrocarbons is one of the thrust areas of research over the years. Designing a robust catalyst, which can work efficiently under eco-friendly conditions for this rea...

We report a covalent porous polymer containing triazine and imine dual active sites that promotes oxygen reduction reaction via push–pull hypothesis.

Photoelectrochemical water-splitting offers unique opportunity in the utilization of abundant solar light energy and water resources to produce hydrogen (renewable energy) and oxygen (clean environment) in the presence of a semiconductor photoanode. Zinc oxide (ZnO), a wide bandgap semiconductor is found to crystallize predominantly in the hexagonal wurtzite phase. Herein, we first report a new crystalline triclinic phase of ZnO by using N-rich antidiabetic drug metformin as a template via hydrothermal synthesis with self-assembled nanorod-like particle morphology. We have fabricated a heterojunction nanocomposite charge carrier photoanode by coupling this porous ZnO with a covalent organic framework, which displayed highly enhanced photocurrent density of 0.62 mA/cm2 at 0.2 V vs. RHE in photoelectrochemical water oxidation and excellent photon-to-current conversion efficiency at near-neutral pH vis-a-vis bulk ZnO. This enhancement of the photocurrent for the porous ZnO/COF nanocomposite material over the corresponding bulk ZnO could be attributed to the visible light energy absorption by COF and subsequent efficient charge-carrier mobility via porous ZnO surface.

Oxygen evolution reaction (OER) is energetically challenging from the platform of making many photovoltaic devices such as metal-air batteries and water splitting systems because of its poor kinetics even when precious metals are used. Herein, a Co(II)-porphyrin/pyrene-comprised conjugated microporous polymer Co-MPPy-1 has been developed which shows efficient OER in alkaline medium. The material was characterized by Fourier transform infrared, solid-state 13C cross-polarization magic angle spinning nuclear magnetic resonance, N2 volumetric adsorption/desorption analysis, scanning electron microscopy, ultra high resolution-transmission electron microscopy, X-ray photoelectron spectroscopy, and other physical studies. Co-MPPy-1 showed Brunauer-Emmett-Teller surface area of ∼501 m2 g-1. Co-MPPy-1 achieved a current density of 1 and 10 mA/cm-2 at 340 and 420 mV, respectively. The turnover frequency calculated for the OER is 0.43 s-1. The heterogeneity of this electrocatalyst was tested by chronoamperometric measurement and 1000 cycle recyclability test with retainment of the excellent electrochemical catalytic activity. This can be attributed to the presence of high density of Co(II) porphyrin unit and efficient charge transport in the π-conductive conjugated polymeric backbone.

Covalent organic frameworks (COFs) build via periodic arrangement of organic building blocks are attracting increasing interest in recent times due to the huge scope in their synthesis through a wide range of structural motifs and diversity in their potential applications. Here we report the synthesis of a new porous extended network π-conjugated TFP-NDA-COF via solvothermal Schiff base condensation of 1,3,5-triformylphloroglucinol (TFP) with 1,5-diaminonaphthalene (NDA). The electrochemical study demonstrates that TFP-NDA-COF has the capability of energy storage up to 379 F g−1 at 2 mV s−1 scan rate, 348 F g−1 at 0.5 A g−1 and offer excellent specific capacitance retention of 75% after 8000 charge discharge cycles. High electrochemical performance could be attributed to the π-electronic conjugation along the polymeric 2D layered network and ion conduction inside the porous channel and permanent porosity of the framework. This indicates that the COF reported herein meets the key requirements like energy storage ability and electrochemical stability needed for developing an efficient energy storage device.

Design and successful synthesis of phenolic-OH and amine-functionalized porous organic polymers as adsorbent for postcombustion CO2 uptake from flue gas mixtures along with high CO2/N2 selectivity is a very demanding research area in the context of developing a suitable adsorbent to mitigate greenhouse gases. Herein, we report three triazine-based porous organic polymers TrzPOP-1, -2, and -3 through the polycondensation of two triazine rings containing tetraamine and three dialdehydes. These porous organic polymers possess high Brunauer–Emmett–Teller (BET) surface areas of 995, 868, and 772 m2 g–1, respectively. Out of the three materials, TrzPOP-2 and TrzPOP-3 contain additional phenolic-OH groups along with triazine moiety and secondary amine linkages. At 273 K, TrzPOP-1, -2, and -3 displayed CO2 uptake capacities of 6.19, 7.51, and 8.54 mmol g–1, respectively, up to 1 bar pressure, which are considerably high among all porous polymers reported till date. Despite the lower BET surface area, TrzPOP-2 and...

We report a new highly crystalline 2D π-conjugated hexagonal mesoporous covalent organic framework material, TrzCOF, through the solvothermal polycondensation of 1,3,5-tri(4-formylbiphenyl) benzene [Ph7(CHO)3, TFBPB] with 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (TAPT) and it displayed excellent anticancer activity for human colorectal carcinoma HCT-116 cells.

The new porous polymer TPDA-1 has been synthesized via solvothermal Schiff base condensation reaction between two organic monomers, i.e., 2,4,6-trihydroxyisophthalaldehyde and 1,3,5-tris(4-aminophenyl)triazine. The TPDA-1 material showed a very high specific capacitance of 469.4 F g–1, at 2 mV s–1 scan rate, together with a high specific surface area of 545 m2 g–1. It also exhibited excellent cyclic stability with 95% retention of its initial specific capacitance after 1000 cycles at 5 A g–1, suggesting its potential as a high performance supercapacitor. Extended π-conjugation and ion conduction inside the micropores throughout the whole polymeric matrix and high BET surface area could be responsible for this high supercapacitor performance in energy storage device. TPDA-1 has been characterized thoroughly by various electrochemical techniques such as cyclic voltammetry, galvanic charge–discharge, and electrochemical impedance spectroscopy. Our experimental results suggested a high potential of this porou...

Metal organic frameworks (MOFs) bearing multicarboxylate linkers are in great demand for designing robust heterogeneous catalysts. A new microporous Ce(III)-based metal organic framework (Ce2NDC3) has been synthesized under solvothermal conditions, which showed strong paramagnetism and a CO2 uptake capacity of 1.64 mmol g−1 (7.23 weight%) at 273 K. The Ce2NDC3 showed high catalytic activity in CO2 fixation for the synthesis of cyclic carbonates with a maximum yield of 92% at ambient temperature and pressure. This rare earth metal-based MOF has been well characterized by single crystal X-ray diffraction, PXRD, N2 adsorption/desorption, UHR-TEM, FESEM, FTIR, 13C MAS NMR and TGA. Here, we have carried out magnetic analysis, which revealed that the Ce(III) in this MOF exhibited 2F5/2 magnetism in the ground state. The Ce2NDC3 catalyst showed high recycling efficiency in CO2 fixation reactions, together with retention of the MOF structure after several rounds of reuse. Presumably, the presence of acidic Ce(III) metal ions and microporosity in the coordinated polymer network is responsible for the high catalytic activity.

Materials with high specific surface area and bearing abundant basic sites at their pore surface are very demanding as heterogeneous catalyst for the eco-friendly base catalyzed reactions. Here we have developed a new secondary amine linked triazine and pyrene containing microporous organic polymer (TrzPyPOP) through a simple polycondensation reaction between tetramine1,4-bis(4,6-diamino-s-triazin-2-yl)-benzene (SL-1) and monoaldehyde pyrene-1-carboxaldehyde. This new porous organic polymer TrzPyPOP is very rich in N-content with high BET surface area (1016 m2 g−1). High surface area and N-rich surface basic sites have been explored in its potential as heterogeneous organocatalyst for the synthesis of dihydropyrimidones via Biginelli condensation involving three-component coupling reaction. Only a very little amount of catalyst was effective for the synthesis of dihydropyrimidones derivatives (yields = 88–99 %) together with high recycling efficiency under the optimum reaction conditions.

Correction for ‘A new triazine based π-conjugated mesoporous 2D covalent organic framework: its in vitro anticancer activities’ by Sabuj Kanti Das et al., Chem. Commun., 2018, 54, 11475–11478.

Covalent organic frameworks (COFs) promise several benefits as materials in terms of gas adsorption, for use in optoelectronic devices, etc. However, the energy storage ability of COFs has not been well studied, especially in sodium batteries. In this report, for the first time, a covalent organic framework (COF), TFPB-TAPT COF, is used as an anode with high capacity in sodium batteries. The TFPB-TAPT COF exhibits an initial reversible capacity of 246 mA h g(-1) and a capacity of 125 mA h g(-1) is retained after 500 cycles. The TFPB-TAPT COF further exhibits Na+ ion storage capability at different current rates. The Na+ ion storage viability of the TFPB-TAPT COF arises mainly because of its open ordered nanoporous framework, which provides reversible accommodation for ions. This work opens up a promising new approach for further utilization of COFs as electrode materials in rechargeable sodium batteries.

A [2 + 2] Schiff base type condensation between 5,10,15,20-tetrakis(4-aminophenyl)porphyrin (TAP) and 1,3,6,8-tetrakis (4-formylphenyl) pyrene (TFFPy) under solvothermal condition yields a crystalline, quasi-two-dimensional covalent organic framework (SB-PORPy-COF). The porphyrin and pyrene units are alternatively occupied in the vertex of 3D triclinic crystal having permanent microporosity with moderately high surface area (∼869 m2 g–1) and promising chemical stability. The AA stacking of the monolayers give a pyrene bridged conducting channel. SB-PORPy-COF has been exploited for metal free hydrogen production to understand the electrochemical behavior using the imine based docking site in acidic media. SB-PORPy-COF has shown the onset potential of 50 mV and the Tafel slope of 116 mV dec–1. We expect that the addendum of the imine based COF would not only enrich the structural variety but also help to understand the electrochemical behavior of these class of materials.

Targeted synthesis of microporous adsorbents for CO 2 capture and storage is very challenging in the context of remediation from green house gases. Herein we report two novel N-rich microporous networks SB-TRZ-CRZ and SB-TRZ-TPA by extensive incorporation of triazine containing tripodal moiety in the porous polymer framework. These materials showed excellent CO 2 storage capacities: SB-TRZ-CRZ displayed the CO 2 uptake capacity of 25.5 wt% upto 1 bar at 273 K and SB-TRZ-TPA gave that of 16 wt% under identical conditions. The substantial dipole quadruple interaction between network (polar triazine) and CO 2 boosts the selectivity for CO 2 /N 2 . SB-TRZ-CRZ has this CO 2 /N 2 selectivity ratio of 377, whereas for SB-TRZ-TPA it was 97. Compared to other porous polymers, these materials are very cost effective, scalable and very promising material for clean energy application and environmental issues.

Designing of low cost catalytic system for new C-C bond formation reactions is very challenging in synthetic organic chemistry. Herein, we report a new copper oxide immobilized covalent organic framework (COF) material CuII-TRIPTA by grafting of CuO nanoparticles at the surface of a nitrogen rich porous COF material TRIPTA. TRIPTA has been synthesized through the extended Schiff base reaction between 2,4,6-triformylphloroglucinol and 1,3,5-tris-(4-aminophenyl) triazine. The COF as well as CuO loaded materials are characterized by powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), N2 adsorption-desorption, Fourier transform infrared spectroscopy (FT-IR), thermogravimetry (TG) and EPR spectroscopic analyses. CuII-TRIPTA material has been successfully applied as heterogeneous nanocatalyst for the C-C homo-coupling reaction of phenylboronic acids to synthesise wide range of biaryl compounds under mild and eco-friendly conditions (60 °C, methanol solvent). Remarkably high specific surface area of CuII-TRIPTA (583 m2 g−1) and highly accessible catalytic sites in the 2D-hexagonal COF nano-architecture potentially makes it excellent catalyst in the C-C bond formation reaction, which is evident from the high TON of the catalyst in this reaction. The catalyst was recollected and reused till 6th cycles without any noticeable change of its catalytic activity, suggesting its high catalytic efficiency in this C-C bond formation reaction.

Functionalized porous organic polymers are very demanding and promising material in heterogeneous catalysis due to their convenience in synthesis and versatility in framework composition. Further, owing to the tunable porosity, high specific surface area, ease of functionalization and chemical stability, this class of porous polymers have huge potential to be employed both as catalysis and catalyst support. Herein, we report N-rich triazine-thiophene based microporous polymer TrzDBTH through the Friedel-Craft alkylation reaction of tripodal building block 2,4,6-tris[4-(bromomethyl)phenyl]-1,3,5-triazine with dibenzothiophene (DBTH) and used it as a heterogeneous base catalyst for one-pot synthesis of biologically important chromene derivatives. Further, sulfonation to this TrzDBTH material yielded sulfonated hyper-crosslinked porous polymer namely STrzDBTH, which can be used as solid acid catalyst for the synthesis of valuable chemical intermediate 5-hydroxymethylfurfural (HMF) from different biomass derived carbohydrates. As a base catalyst, TrzDBTH provides chromene yields from 88 to 93% and its sulfonated derivative STrzDBTH provides the HMF yields from 57 to 97% for different carbohydrate substrates. Both the materials displayed high recycling efficiencies for several catalytic cycles. Thus, these triazine-thiophene based porous organic polymers offer very economical, scalable and recyclable routes for the synthesis chromene derivatives and HMF.

The new covalent organic framework material TDFP-1 was prepared through a solvothermal Schiff base condensation reaction of the monomers 1,3,5-tris-(4-aminophenyl)triazine and 2,6-diformyl-4-methylphenol. Owing to its high specific surface area of 651 m2 g−1, extended π conjugation, and inherent microporosity, TDFP-1 exhibited an excellent energy-storage capacity with a maximum specific capacitance of 354 F g−1 at a scan rate of 2 mV s−1 and good cyclic stability with 95 % retention of its initial specific capacitance after 1000 cycles at 10 A g−1. The π-conjugated polymeric framework as well as ionic conductivity owing to the possibility of ion conduction inside the micropores of approximately 1.5 nm make polymeric TDFP-1 a favorable candidate as a supercapacitor electrode material. The electrochemical properties of this electrode material were measured through cyclic voltammetry, galvanic charge–discharge, and electrochemical impedance spectroscopy, and the results indicate its potential for application in energy-storage devices.