Oxygen electrocatalysis plays a pivotal role in energy conversion and storage technologies. The precise identification of active sites for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is crucial for developing an efficient bifunctional electrocatalyst. However, this remains a challenging endeavor.
View Article and Find Full Text PDFNoble metal-based catalyst, despite their exorbitant cost, are the only successful catalyst for bifunctional oxygen electrocatalysis owing to their capability to drive forward the reaction rate kinetically. Therefore, it is desirable to diminish the noble metal loading without any compromise in the catalyst performance. In this study, the aim to achieve two goals with one action via a single-step route to have ultra-low loading of Pd in the catalyst.
View Article and Find Full Text PDFA large number of scientific investigations are needed for developing a sustainable solid sorbent material for precombustion CO capture in the integrated gasification combined cycle (IGCC) that is accountable for the industrial coproduction of hydrogen and electricity. Keeping in mind the industrially relevant conditions (high pressure, high temperature, and humidity) as well as good CO/H selectivity, we explored a series of sorbent materials. An all-rounder player in this game is the porous organic polymers (POPs) that are thermally and chemically stable, easily scalable, and precisely tunable.
View Article and Find Full Text PDFAmmonia is a crucial biochemical raw material for nitrogen containing fertilizers and a hydrogen energy carrier obtained from renewable energy sources. Electrocatalytic ammonia synthesis is a renewable and less-energy intensive way as compared to the conventional Haber-Bosch process. The electrochemical nitrogen reduction reaction (eNRR) is sluggish, primarily due to the deceleration by slow N diffusion, giving rise to competitive hydrogen evolution reaction (HER).
View Article and Find Full Text PDFN-rich organic materials bearing polyphenolic moieties in their building networks and nanoscale porosities are very demanding in the context of designing efficient biomaterials or drug carriers for the cancer treatment. Here, we report the synthesis of a new triazine-based secondary-amine- and imine-linked polyphenolic porous organic polymer material TrzTFPPOP and explored its potential for in vitro anticancer activity on the human colorectal carcinoma (HCT 116) cell line. This functionalized (-OH, -NH-, -C=N-) organic material displayed an exceptionally high BET surface area of 2140 m g along with hierarchical porosity (micropores and mesopores), and it induced apoptotic changes leading to high efficiency in colon cancer cell destruction via p53-regulated DNA damage pathway.
View Article and Find Full Text PDFCancer, 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.
View Article and Find Full Text PDFA new significant feature of a triazine-based covalent organic polymer electrocatalyst is demonstrated. The metal-free electrocatalyst has dual-active sites, which enable it to entangle oxygen a push-pull interaction that plays a crucial role in promoting the oxygen reduction reaction.
View Article and Find Full Text PDFThe development of an efficient, sustainable, and inexpensive metal-free catalyst for oxygen evolution reaction (OER) photoelectrochemical water splitting is very demanding for energy conversion processes such as green fuel generators, fuel cells, and metal-air batteries. Herein, we have developed a metal-free pyrene-based nitrogen and sulfur containing conjugated microporous polymer having a high Brunauer-Emmett-Teller surface area (761 m g) and a low bandgap of 2.09 eV for oxygen evolution reaction (OER) in alkaline solution.
View Article and Find Full Text PDFPurpose: The pandemic of coronavirus disease 2019 (COVID-19) has cost numerous lives and induced tremendous mental stress among people. The purpose of this research was to determine anxiety and depression levels, clinical features, and the connections between demographic variables and depression prevalence as well as anxiety prevalence among reported COVID-19 cases in Bangladesh.
Methods: For the purpose of data collection, an online cross-sectional survey was carried out from May 26 to June 27, 2020, utilizing a Google adapted preformed questionnaire.
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 C cross-polarization magic angle spinning nuclear magnetic resonance, N volumetric adsorption/desorption analysis, scanning electron microscopy, ultra high resolution-transmission electron microscopy, X-ray photoelectron spectroscopy, and other physical studies.
View Article and Find Full Text PDFMetal organic frameworks (MOFs) bearing multicarboxylate linkers are in great demand for designing robust heterogeneous catalysts. A new microporous Ce(iii)-based metal organic framework (CeNDC) has been synthesized under solvothermal conditions, which showed strong paramagnetism and a CO uptake capacity of 1.64 mmol g (7.
View Article and Find Full Text PDFA [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 m g) and promising chemical stability. The AA stacking of the monolayers give a pyrene bridged conducting channel.
View Article and Find Full Text PDFThe 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 m g , extended π conjugation, and inherent microporosity, TDFP-1 exhibited an excellent energy-storage capacity with a maximum specific capacitance of 354 F g at a scan rate of 2 mV s and good cyclic stability with 95 % retention of its initial specific capacitance after 1000 cycles at 10 A g . The π-conjugated polymeric framework as well as ionic conductivity owing to the possibility of ion conduction inside the micropores of approximately 1.
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