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A novel N-rich sugarcane-like photocatalyst CdS/C3N5 (CCN) was prepared by a thermal polymerization method and tested for generating H2 and realizing antiphotocorrosive performance. The best photocatalytic H2 evolution is obtained for a CdS to C3N5 mass ratio of 1:1 (CCN3), which is nearly 33 and 3 times higher than that of pure C3N5 and CdS, respectively. CCN3 can be used to effectively reduce CdS photocorrosion and increase stability because of its N-rich performance and sugarcane-like structure, which can affect electron transport and enhance the internal binding force, respectively. CCN3 can maintain a high H2 evolution ability after 5 cycles, while still maintaining the original sugarcane-like shape, which has an anti-photocorrosive ability.

A convenient and efficient synthesis of a series of ethyl-1-(6-(4-substitutedacetylatedpiperazin-1-yl)pyrimidin-4-yl)-5-amino-1H-pyrazole-4-carboxylate (8a-8j) has been developed by five steps which include activation of a methylene group, hydrazinolysis, cyclisation and chloro-amine coupling reactions. Moreover, our proposed mechanism was confirmed in this study demonstrating that ethyl 5-amino-1-(6-chloropyrimidin-4-yl)-1H-pyrazole-4-carboxylate is the key intermediate to fulfill the desired outcomes. In silico and in vitro studies were carried out to identify the active agents among the developed adducts against mycobacterium tuberculosis (PDB ID:4TRO). Compound 8a (Docking Score: -26.81 and MIC: 1.6 ug/mL) was found to be the most potent among the synthesized molecules. All the synthesized compounds showed acceptable drug-like properties which make them suitable for further lead modification using in silico design approaches.

The medical and related healthcare and hygiene sector is the most important and growing part of the textile industry. Due to recent development and advancement in polymer science, the research fraternity explored variety of polymers in medical applications ranging from a single thread suture to the complex composite structures for the replacement of bone and cartilage, and from simple cleaning wipes used in operation rooms to advanced barriers fabrics, all are majorly categorised as health care and hygiene products, extracorporeal, implantable and non –implantable devices. The polymers with desirable properties such as bio-compatibility, non-toxic, non-allergic, non-carcinogenic and good mechanical properties like flexibility, durability and strength have found diverse specialized applications. Chitin, the nitrogen rich polysaccharide has many bio active properties such as anti-bacterial, anti-viral and anti-fungal, which are promising for use in pharmaceutical and scaffolds applications. Protein based natural polymers like collagen; albumin and gelatine are used as membranes for wound healing. Polymeric materials like hydrogels and bio-degradable polymers are inherently capable of taking care of the infection in sutures and wound dressings, also preventing pollution. Polymers with bio active coatings or bio functional surfaces like herbal agents, nano-silver and plasma offer desired anti-microbial features on material surface required in health care regime. Biological, natural or synthetic derived biopolymers find major application as haemostats due to their structural integrity, flexibility and ease of handling. Shape memory and conductive polymers add unimaginable scope in therapeutic care. This paper presents an overview of polymers used in medical and health care textiles and their wide spread applications classified as in the patient, on the patient, for the patient and near the patient. The future holds bounteous scope for research in the fields of bio-polymers and medical sciences, which help in improving healthcare quality globally by introducing meaningful, new and invaluable products to market.

Rising atmospheric CO2 levels and water pollution have necessitated new research towards the development of novel CO2 capture materials and innovative methods for waste water treatment. Herein, we demonstrate a facile fabrication strategy to prepare novel template-shape replicated nitrogen-rich mesoporous carbon nanospheres (NMCN) with high surface area, pore volume and ordered pore geometry via in situ co-condensation, surface-confined atom transfer radical polymerization (SC-ATRP) and post-polymerization modification. NMCN exhibited efficient CO2 capture ability (up to 4.93 mmol g-1) at ambient temperature and contaminant removal capability from waste water. This work may open a new direction for the design of novel porous carbon materials for CO2 capture and other emerging applications.

Covalent organic frameworks (COFs) have emerged as highly crystalline porous organic materials and proved to be the potential candidates for various interesting applications, such as gas adsorption and separation, catalysis, energy storage, and sensing, etc. Fluorescence-based sensing has gained great attention due to its high selectivity, rapid response time, and real-time monitoring. Lately, luminescent COFs have come to the fore as sensing probes to detect the various target molecules. In this review, we have targeted a comprehensive account of the chronological development of the field of COFs starting from 2005 till date. We have described the design principle with a focus on various topologies reported, classification of their structural diversity on the basis of thirty-two linkages and dimensionality, methods of synthesis with examples, and the use of various characterization techniques. Interestingly, almost one-half of the COFs contains linkages that are nitrogen-rich. With a background in different processes involved for fluorescence sensing, we have illustrated the potential applicability of nitrogen-rich COFs as sensors for numerousanalytes, such as explosives, volatile organic molecules, pH, temperature, toxic anions, metal ions and biomolecules from different media utilizing the striking features of COFs with predesigned structures and diverse functionality.

High-nitrogen energetic compounds are widely used in military and civil fields. To cope with some special conditions, materials with high melting point and good heat resistance are required. Herein, synthetic approach of two TACOT-derived compounds with high heat resistance and strong insensitivity for friction has been optimized. Significantly, 100 g-scale of aza-TACOT(I) was prepared with a total yield of 80% and a purity of 99.9%. Meanwhile, aza-TACOT(II) was obtained with a purity of 98.9% under the optimized conditions. This practical method features scalable and simple operations. In addition, an acceptable mechanism was firstly proposed for the critical step.

Nitrogen-rich compound 5,5′-(4-nitro-1H-pyrazole-3,5-diyl)-bis-(4H-1,2,4-triazole-3,4-diamine) (4) and its energetic salts (5–8) were synthesized. Compounds 4–7 posesse satisfactory mechanical sensitivity (IS > 40 J, FS > 360 N). 4 and 5 have the higher decomposition temperatures (4, 318 °C and 5, 304 °C) than TNT (TNT, 295 °C). Compared with TATB (8114 m•s−1), the calculated detonation velocity of 8 (8716 m•s−1) has a certain advantage. Multi-factor analysis shows that these compounds are promising nitrogen-rich energetic materials.

The emerging class of heptazine-based polymeric materials has shown potential candidature as photocatalyst materials for hydrogen evolution. At the same time, they have shown promising application as solid base materials to catalyse various organic transformations. Thus, the material design rationale needs to be developed around the heptazine-based polymeric frameworks in order to specifically design task specific materials. Herein, we utilised controlled reaction conditions to synthesize the desired polymeric networks with trichloroheptazine as precursor. Material design strategy employed nitrogen rich [tris(2-aminoethylamine) and hydrazine] as soft linkers to understand the effect on band structure of developed heptazine-based polymeric networks. The developed polymeric networks were explored as platform to study systematically the effect on their respective photophysical properties and understand their surface basicity. The framework having aminoalkyl linker showed superior activity in photocatalysis as well as heterogeneous base catalysis. Further, model catalysts revealed the importance of N-atoms as active basic sites in these systems.

The emerging metal-free carbon nitride (C3N4) offers prominent possibilities for realizing the highly effective hydrogen evolution reaction (HER). However, its poor surface conductivity and insuffi...

Herein, we present a hierarchical structure consisting of an expanded interlayer, which comprises MoS2 dispersed onto and diffused into nitrogen-doped carbon nanotubes (MoS2-CNTPPys), as an electro...

Summary The capture of radioiodine species during nuclear fuel reprocessing and nuclear accidents is crucial for nuclear safety, environmental protection, and public health. Previously reported emerging materials for iodine uptake cannot outperform commercial zeolites and active carbon under the practical dynamic scenario. Herein, we present a new design philosophy aiming at significantly enhanced specific host-guest interactions and obtain a nitrogen-rich covalent organic framework material by introducing a bipyridine group into the building block for the simultaneous capture of both iodine gas through enhanced electron-pair effect and organic iodide via the methylation reaction. These efforts give rise to not only an ultrahigh uptake capacity of 6.0 g g−1 for iodine gas and a record-high value of 1.45 g g−1 for methyl iodide under static sorption conditions but also, more importantly, a record-high iodine loading capability under dynamic conditions demonstrated from the breakthrough experiments.

Metal–organic frameworks (MOFs) and covalent–organic frameworks (COFs) are promising precursors for preparing high-performance carbonaceous materials for capacitive deionization (CDI). However, the...

Reactivity of low-valent AlII species containing redox-active dpp-dad or dpp-Bian ligand (La = dpp-dad = [(2,6-iPr2C6H3)NC(CH3)]2; Lb = dpp-Bian = 1,2-[(2,6-iPr2C6H3)NC]2C10H6) toward nitrogen-rich...

Anaerobic digestion of nitrogen-rich organic wastes as the sole feedstock does not only have low efficiency in methane production due to its inherent carbon deficiency (low carbon/nitrogen ratio) b...

Two series of both nitrogen-rich and thermostable energetic materials as well as their energetic salts based on hetarenecarboxylic acids are now described. Among these new compounds, neutral compounds 3 and 10 have higher nitrogen contents (69.66% and 63.05%) than their energetic salts, which suggests that they could be used as green energetic materials. In addition, compound 3 shows a good decomposition temperature (Td = 281 °C), which is close to that of TNT (Td = 295 °C). Nitrogen-rich salt 6 exhibits better integrated energetic-properties (D = 8913 m s−1, IS = 24 J, FS = 320 N) than RDX (D = 8795 m s−1, IS = 7.5 J, FS = 120 N).

We have carried out an extensive search for stable polymorphs of carbon nitride with C3N5 stoichiometry using the minima hopping method. Contrary to the widely held opinion that stacked, planar, graphite-like structures are energetically the most stable carbon nitride polymorphs for various nitrogen contents, we find that this does not apply for nitrogen-rich materials owing to the high abundance of N–N bonds. In fact, our results disclose novel morphologies with moieties not previously considered for C3N5. We demonstrate that nitrogen-rich compounds crystallize in a large variety of different structures due to particular characteristics of their energy landscapes. The newly found low-energy structures of C3N5 have band gaps within good agreement with the values measured in experimental studies.

By employing a mixed metal synthesis strategy, a heterometallic MOF, [In3Tb3O3(TATAB)4(H2O)6]·12DMF·12H2O (1), has been constructed based on a nitrogen-rich ligand 4,4′,4′′-s-triazine-1,3,5-triyltri-p-aminobenzoic (H3TATAB). Compound 1 shows a 3D doubly interpenetrated framework built from dual-walled cages of dimension ca. 2.8 nm. In particular, the framework of 1 possesses a high density of Lewis acidic metal ions and Lewis basic –NH– sites decorated on the pore walls. Fluorescent sensor study indicates that 1 can maintain its stability and agility after several cycles of detecting nitenpyram, and the detection limit of 1 for nitenpyram is as low as 0.17 μg mL−1.

The chemistry of high-energy-density materials (HEDMs) featuring multiple nitrogen-rich heterocyclic skeletons with energetic fragments has witnessed enormous growth since the process of manufacturing explosives successfully was improved by Alfred Nobel. In particular, the recent surge of interest in HEDMs is because of its wide application in the military and civilian fields. In this review, we provide a systematic introduction to the developments in heterocyclic nitrogen-rich energetic materials with various explosive groups in the form of tricyclic-based compounds. This review summarizes the recent efforts toward new HEDMs based on the synthetic route, crystal behavior and the structure–property relationship. Further studies on new nitrogen-rich heterocycles may be helpful to achieve a more sustainable chemical process, which could make a positive impact of chemistry, not only for HEDMs, but also in other fields.

Pressure-induced non-molecular phases of polymeric nitrogen have potential applications in the field of energetic materials. Here, through a structural search method combined with first-principles calculations, we have predicted four novel nitrogen-rich aluminum nitrides C2/m-AlN6, Cm-Al2N7, C2-Al2N7 and P1-AlN7. Nitrogen atoms polymerize into infinite chains in C2/m-AlN6, C2-Al2N7 and P1-AlN7 structures and form N3 chains and N4 rings in Cm-Al2N7. C2/m-AlN6 is stable in the pressure range from 30 to 80 GPa and Cm-Al2N7, C2-Al2N7 and P1-AlN7 are metastable in the pressure ranges of 35–65, 65–80 and 41–80 GPa, respectively. The present study predicts that C2/m-AlN6 has a superconducting transition temperature of 18.9 K at 0 GPa and can be quenched and recovered under ambient conditions. The energy densities of C2/m-AlN6, Cm-Al2N7, C2-Al2N7 and P1-AlN7 compounds are expected to be 4.80, 4.59, 5.46 and 5.59 kJ g−1, respectively, due to their high nitrogen content, indicating that they have potential to be high-energy density materials. The calculated Vickers hardness of C2/m-AlN6, Cm-Al2N7, Cm-Al2N7 and P1-AlN7 is 43.86, 39.32, 63.96 and 33.58 GPa, respectively, showing that the novel nitrogen-rich aluminum nitrides are potential superhard materials as well. This study may encourage further experimental exploration of high N content superhard or high-energy density nitrides.

This research focuses on the exploration of giant reed (Arundo donax L., AD) as a viable and underutilized sustainable resource for the development of energetic nitrogen-rich dense biopolymers base...

Three new lanthanide metal–organic frameworks IRHs-(1–3) supported by cyamelurate linkers have been synthesized and structurally characterized. The incorporation of numerous heteroatoms (N and O) i...

Seven energetic salts of 3,6-dinitramino-1,2,4,5-tetrazine (DNAT), named as (NH4)2(DNAT) (1), (NH2NH3)2(DNAT) (2), (NH3OH)2(DNAT) (3), G2(DNAT) (4) (G = guanidine), (AG)2(DNAT) (5) (AG = aminoguani...

In this paper, four kinds of guanidinium dicyanamide-based energetic salts were prepared and investigated as energetic additives to hypergolic ionic liquid 1-ethyl-3-methyl imidazolium dicyanamide ...

A new metal–organic framework was prepared based on a mixed ligand system of the designed nitrogen-rich 3,6-bis(2-methylimidazole)pyrimidine (b2mpm) and benzophenone 4,4′-dicarboxylic acid (H2bpndc...

In the present study, we have successfully synthesized nitrogen-rich graphitic carbon nitride (g-C3N4) nanosheets by a simple direct thermal polymerization approach. The synthesized g-C3N4 nanosheets were exfoliated using HCl to make their surface a few nanometers thick. The ultrathin surface was achieved by simply mixing g-C3N4 in 3 M HCl. After that, palladium nanoparticles were uniformly immobilized on the surface of g-C3N4. The synthesized materials were characterized by various physiochemical techniques such as X-ray diffraction, energy-dispersive X-ray spectroscopy, and Fourier transform infrared spectroscopy. Information about morphology and size was obtained through transmission electron microscopy and scanning electron microscopy. The Brunauer–Emmett–Teller surface area, pore volume, and pore diameter were determined using nitrogen adsorption–desorption measurements. The prepared material (Pd/g-C3N4) was utilized as an efficient catalyst for the reduction of hazardous nitroarenes and degradation of organic dyes. The catalyst could be easily recovered through centrifugation and then could be reused multiple times for the further catalytic cycles with a little loss in its catalytic activity. The work presented here illustrates the sustainable anchoring of metal nanoparticles over the surface of nitrogen-rich g-C3N4 nanosheets and could be utilized for different types of catalytic reactions.

Fused heterocyclic energetic cation was rarely reported despite the development of energetic cation has attracted increasing attention in recent years. In this work, a new 1H-imidazo[4,5-d]pyridazi...

Emerging quantum technologies require the fabrication of diamonds that contain single defects with specific optical, electronic, and magnetic properties. We report on the results of an annealing st...

A series of highly nitrogen-rich microporous polymers are prepared from triazine-based tetraamines (p-BzDAT and m-BzDAT) and hexaamine (TMBDAT) with formamide (MF) and N,N-dimethylformamide (DMF). ...

Semiconductive nitrogen-rich tantalum nitrides including Ta4N5 and Ta3N5 are successfully synthesized via an ammonia looping process by space-confined thermal decomposition of a unique Ta–(NCNH2)x precursor. This novel approach not only breaks the limit of requiring small-sized tantalum precursors but also considerably reduces ammonia usage in comparison to conventional nitridation methods (0.9 liter vs. 36 liters).

Sodium ion batteries (SIBs) have attracted considerable attention as an alternative to Li ion batteries (LIBs) because of the sustainable sodium resources and similar chemistry to LIBs. On the other hand, the larger and heavier sodium results in unfavorable sodium ion storage capacity. In this study, an inexpensive precursor-based conversion material, FeS2, was synthesized as a nanostructured pyrite crystal

An organic crystalline salt 2,4-diamino-6-methyl-1,3,5-triazinium trifluroacetate (DMTFA) has been imposed for experimental and theoretical investigation. Gaussian 09 program has been used to compute the quantum chemical theoretical calculations. DFT/B3LYP-6-311++G(d,p) approach is adapted to optimize the structure. Structural and vibrational studies have been carried out by this approach followed by the correlation of experimental and theoretical results. Natural bonding orbital analysis, molecular electrostatic potential and frontier molecular orbital investigations substantiates the charge transfer besides the presence of strong inter and intra molecular interactions. Apart from the three dimensional Hirshfeld surface analysis and two dimensional fingerprint maps provides profund vision about the intermolecular interactions between the molecules.

Two-photon fluorescent (TPF) probes, which allow imaging of biological events in a high spatiotemporal resolution, are in great demand. Recently, carbon quantum dots (CQDs) have emerged as a promising class of TPF probes. Unfortunately, the use of the existing CQDs has been limited by their weak TPF capacities. Herein, we report the first facile and large-scale synthesis of nitrogen-rich CQDs (NRCQDs) based on a donor-π-acceptor (D-π-A) strategy. The resulting NRCQDs demonstrated a tremendous TPF capacity with a two-photon absorption cross section (TPACS) and quantum yield (QY) up to 61 200 Göppert-Mayer (GM) units and 63%, respectively, which is greater than those that could be achieved by the existing TPF carbon probes. Structural and optical analyses of NRCQDs revealed that the great TPF capacity is contributed by the nitrogen-rich D-π-A structure as well as the high crystallinity, large plane, rigid, graphitic nitrogen-doped π-conjugated system. We further demonstrated that NRCQDs allow imaging of live cells as well as live liver tissues at depths of up to 440 μm. Our results suggest NRCQDs as a robust TPF probe that can be potentially used for a variety of biological applications.

MoS2 nanosheets were hybridization with a cobalt-embedded nitrogen-rich graphene networks (Co@N-GNWs) to tune the electrochemical hydrogen evolution activity. Experimental observation and theoretic...

The exploration of a noble-metal-free and nitrogen-doped carbon (M-N/C) composite electrocatalyst for the oxygen reduction reaction (ORR) remains a great challenge. The activities of the M-N/C composite electrocatalysts are mainly affected by the metal active sites, pyridinic nitrogen, and graphitic nitrogen. In the present work, the iron-coordinated self-assembly is proposed for the preparation of iron-chelating pyridine nitrogen-rich coordinated nanosheet (IPNCN) composites as an electrocatalyst. Due to the highly conjugated structure of the IPNCN precursor, the pyridine nitrogen elements at both ends of the tetrapyrido [3,2-a:2',3'-c:3'',2''-h:2''',3'''-j] phenazine (TP) provide the multiple ligands, and the coordination interactions between the irons and the pyridine nitrogen further improve the thermodynamic stability, where the metal active sites and nitrogen elements are uniformly distributed in the whole structure. The resultant IPNCN composites exhibit excellent ORR performance with an onset potential of 0.93 V and a half potential of 0.84 V. Furthermore, the IPNCN composite electrocatalysts show the higher methanol resistance and electrochemical durability than the commercial Pt/C catalysts. It could be convinced that the as-designed IPNCN composite catalysts would be a promising alternative to the noble metal Pt-based catalysts in the practical applications.

Cu(II)-modified nitrogen-rich covalent organic polymer (Cu/N-COP-1) was fabricated and employed to catalyze the cross-dehydrogenative ortho-aminomethylation of phenols. The Cu/N-COP-1 catalyst displayed excellent catalytic activity under mild conditions without any ligand. Various substituted phenols and N,N-dimethylanilines were successfully converted to the corresponding products. Moreover, the catalyst can be readily reused for at least five consecutive runs without obvious loss of catalytic activity. This can be attributed to the interaction between the nitrogen-containing group of the covalent organic polymer and Cu species, which makes Cu species steadily immobilized on the surface of polymer.