Rapid template-free synthesis of an air-stable hierarchical copper nanoassembly and its use as a reusable catalyst for 4-nitrophenol reduction

A hierarchical copper nanoassembly was synthesized by one-pot solvothermal treatment at 150 degrees C for 2 h in the presence of copper nitrate, formamide and water. The product exhibited phase pure hierarchical Cu microspheroids (2-7 mu m) comprising a nanorod (50-100 nm) assembly. The Cu microspheroids showed excellent air-stability, antioxidative properties and catalytic reduction of p-nitrophenol

Triazine containing N-rich microporous organic polymers for CO2 capture and unprecedented CO2/N2 selectivity

Targeted synthesis of microporous adsorbents for CO2 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 CO2 storage capacities: SB-TRZ-CRZ displayed the CO2 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 CO2 boosts the selectivity for CO2/N2. SB-TRZ-CRZ has this CO2/N2 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

Bifunctionalized Mesoporous SBA-15: A New Heterogeneous Catalyst for the Facile Synthesis of 5‑Hydroxymethylfurfural

Bifunctional porous nanomaterials are very demanding in the context of heterogeneous catalysis. A highly ordered 2D-hexagonal bifunctionalized mesoporous SBA-15 type material MPBOS (mesoporous bifunctionalized organosilica) has been synthesized via a post synthetic route. The surface of the SBA-15 has been functionalized with (3-chloropropyl)­triethoxy­silane to obtain MPCOS (mesoporous chloro-substituted organosilica) material, which undergoes an S_N2 substitution reaction of the surface a grafted chloro group with the amine group of organic ligand 5-amino­isophthalic acid, in the presence of potassium carbonate under refluxing conditions, offering the bifunctional material MPBOS. The bifunctionalized material with exceptionally high Brunauer–Emmett–Teller (BET) surface area of 652 m² g^–1 and average pore diameter of 9.4 nm has been characterized thoroughly with powder X-ray diffraction (PXRD), N₂ sorption analysis, solid state ¹³C cross-polarization magic angle spinning nuclear magnetic resonance (CP MAS NMR) spectroscopy, Fourier transform infrared (FT-IR), and UV–vis spectroscopy, high-resolution transmission electron microscopy (HR-TEM), field emission scanning electron microscopy (FE-SEM), thermogravimetric differential thermal analysis (TG/DTA), NH₃ temperature programmed desorption (NH₃-TPD), and CHN analysis. The total acidity of this material has been determined from the NH₃-TPD analysis, and this is estimated as 1.94 mmol g^–1. The acidic and basic sites present in this bifunctionalized material have been explored in catalytic conversion of abundant carbohydrates to hydroxy­methyl­furfural (HMF) with the highest yield of 74 mol % from fructose in organic polar solvent dimethyl sulfoxide (DMSO) under microwave assisted heating conditions

Novel porous metal phosphonates as efficient electrocatalysts for the oxygen evolution reaction

Recently, metal-doped organic-inorganic hybrid nanomaterials have attracted substantial attention for their high catalytic activity in the electrochemical oxygen evolution reaction (OER). Here, we report three novel porous metal phosphonates, cobalt phosphonate (CoPIm), nickel phosphonate (NiPIm), and nickel-cobalt phosphonate (NiCoPIm), using iminodi(methylphosphonic acid) as an organophosphorous precursor via a hydrothermal nontemplated synthetic route. All three materials have been explored as electrocatalysts for the OER. Notably, the CoPIm material exhibits excellent electrocatalytic behavior among all of the as-prepared catalysts. The high surface area and the formation of active CoOOH species on the catalyst surface during the OER process are the main driving force for a superior electrochemical OER. The CoPIm catalyst requires a very small overpotential (334 mV) to reach the current density of 10 mA cm in 1.0 M KOH solution with a Tafel slope of 58.6 mV dec as compared to NiPIm, NiCoPIm, and commercial IrO. Additionally, the prepared CoPIm catalyst shows excellent stability up to 25 h, suggesting its potential in electrochemical water splitting

Crystalline porous organic polymer bearing -SO3H functionality for high proton conductivity

Designing high-performing proton-conducting materials with in-built -SOH moieties in the crystalline organic framework is very challenging in the context of developing an efficient solid electrolyte for fuel cells. Herein, we report a simple chemical route for synthesizing crystalline microporous sulfonic acid-functionalized porous organic polymers (MPOPS-1) via extended condensation polymerization between two organic monomers (i.e., cyanuric chloride and 2,5-diaminosulfonic acid) under refluxing conditions. The crystal structure of this organic framework has been indexed from powder X-ray diffraction data, revealing a monoclinic phase with a unit cell volume of 1627 Å. The presence of in-built sulfonic acid groups in MPOPS-1 contributes significantly to the high proton conductivity of this porous organic polymer. The resulting MPOPS-1 displays proton conductivities of 1.49 × 10 and 3.07 × 10 S cm at 350 K temperature under anhydrous and humid conditions, respectively, outperforming many previously reported porous organic polymers

Microporous nickel phosphonate derived heteroatom doped nickel oxide and nickel phosphide: Efficient electrocatalysts for oxygen evolution reaction

Designing low-cost and highly efficient electrocatalysts based on widely abundant elements is highly desirable for future green energy production. Transition metal oxides and phosphides have recently been demonstrated to be promising and cost-effective electrocatalysts due to their distinct surface properties and good conductivity. Herein, we have synthesized a new microporous organic-inorganic hybrid nickel phosphonate (NiPPA) material under hydrothermal reaction condition without the use of structure directing agent. The microporous NiPPA material can be converted to N, P-codoped nickel oxide (NP/NiO) and N, O-codoped nickel phosphide (NO/NiP) following pyrolysis under air and nitrogen atmospheres, respectively. These high surface area materials are subsequently explored as electrocatalysts towards oxygen evolution reaction (OER) in alkaline media. Among the three catalysts, NP/NiO exhibits the highest electrocatalytic activity for OER with an overpotential of 332 mV to reach a current density of 10 mA cm and a low Tafel slope of 65.6 mV dec in 1.0 M KOH solution. Furthermore, the as-prepared NP/NiO catalyst displays an outstanding stability over a period of 15 h, suggesting the high durability of this catalyst for OER

Pd NP-Decorated N‑Rich Porous Organic Polymer as an Efficient Catalyst for Upgradation of Biofuels

Hydrodeoxygenation process is a potential route for upgrading biofuel intermediates, like vanillin, which is obtained in huge quantities through the chemical treatment of the abundant lignocellulosic biomass resources of nature, and this is attracting increasing attentions over the years. Herein, we report the grafting of palladium nanoparticles at the surface of porous organic polymer Pd-PDVTTT-1 synthesized through the co-condensation of 1,3,5-triallyl-1,3,5-triazine-2,4,6-(1<i>H</i>,3<i>H</i>,5<i>H</i>)-trione and divinylbenzene in the presence of radical initiator under solvothermal reaction conditions. The Pd-PDVTTT-1 material has been characterized thoroughly by powder X-ray diffraction, nitrogen sorption, ultra-high-resolution transmission electron Microscopy, Fourier-transform infrared spectroscopy, ¹³C MAS NMR, and X-ray photoelectron spectroscopy analyses. High surface area together with good thermal stability of the Pd-PDVTTT-1 material has motivated us to explore its potential as heterogeneous catalyst in the hydrodeoxygenation of vanillin for the production of upgraded biofuel 2-methoxy-4-methylphenol in almost quantitative yield and high selectivity (94%)