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Chemical warfare agents (CWAs) have been classified as fatal weapons of mass destruction because of their toxicity and deadly consequences. Among other CWAs, sulfur mustards (HDs) were employed during the Iraq–Iran war (1984–1988), causing significant fatal effects for 100 000 military and civilian Iranians, and around 45000 people are still suffering from long-term health repercussions. Hence, the detection and detoxification of these acutely dangerous chemicals are critical for protecting ourselves and have thus sparked much scientific interest around the globe. In this regard, studies show that various photoresponsive porous organic materials like activated metal–organic-frameworks (MOFs), porous organic polymers (POPs), covalent organic frameworks (COFs), and TiO2-derived materials are highly effective for the photochemical detoxification of HDs. Given this context, we have traversed through the history of developing various photoresponsive porous materials and their efficacy in detoxifying CWAs, notably HDs. Moreover, we highlighted the numerous research methodologies reported to detect and modulate the excitonic effects in photoporous materials, which can tune the in situ-generated reactive oxygen species (ROS) responsible for HD detoxification. Lastly, we have listed the hurdles in creating photoactive porous materials and functionalizing them for large-scale HD detoxification. Although most of the described porous photocatalysts demonstrated good lab-scale performance, relatively few are accessible for large-scale industrial use. We have also addressed the future needs and potential for employing photoporous materials for efficient detoxification of HDs on an industrial scale to alleviate the issue of CWA/HD stockpiling and their potential use as a weapon of mass destruction. [ABSTRACT FROM AUTHOR]

The electrochemical fixation of carbon dioxide (CO2) into organic halides is one of the most prominent strategies for mitigating atmospheric CO2 emission, along with the difficulties associated with the toxic and carcinogenic halogenated compounds. Cu-based nanomaterials have been explored for numerous applications in nanotechnology, including electrocatalysis, organic catalytic transformations, and photocatalysis. In this work, we have designed and developed a Cu-embedded carbazole-derived porous organic polymer (Cu@Cz-POP) nanohybrid by utilizing the Friedel–Crafts alkylation approach and employing 1,4-dimethoxybenzene as the cross-linking agent comprising unique characteristic features of the extended π-conjugated system along with an active metal center with tunable electrochemical properties. The Brunauer–Emmett–Teller surface area of the conjugated Cz-POP is found to be 1060 m2 g–1. The X-ray photoelectron spectroscopy (XPS) study demonstrates the formation of CuO nanoparticles in the polymeric framework. X-ray absorption fine structure analysis (EXAFS) also reveals the existence of CuO with a smaller fraction of Cu in the polymeric framework, which is corroborated with the XPS analysis. The Cu@Cz-POP nanohybrid is fabricated by drop-casting over a Ni foam, showing promising electrocatalytic activity toward electrocarboxylation of benzyl bromide in 0.1 M TBA·BF4/CH3CN with saturated CO2 medium with a current density of 120 mA cm–2 delivering 65% yield of phenylacetic acid (PAA) as the primary product along with traces of benzyl 2-phenylacetate (BPA) and 1,2-diphenylethane (DPE), and the turnover frequency is found to be 8.556 × 10–7 s–1. Density functional theory calculations demonstrate that CuO is adsorbed more favorably at the N1 nitrogen atom of Cz-POP. An electron transfer from the N1 atom and the aromatic rings of Cz-POP to the CuO center is observed and confirmed by the overlap of alpha orbitals. [ABSTRACT FROM AUTHOR]

We have introduced a Friedel–Crafts alkylation strategy of a Ni-salphen complex as derived from 2-hydroxy-5-methoxybenzaldehyde, an isomer of biomass derived vanillin, to construct a Ni-salphen based porous organic polymer (Ni@T-POP). The X-ray absorption spectroscopy (XAS) analysis revealed the existence of Ni–N2O2 core sites in the Ni@T-POP framework, which demonstrates unprecedented catalytic efficiency towards oxidative decontamination of sulfur mustards (HD's) compared to its complex precursor. [ABSTRACT FROM AUTHOR]

Summary: Fifth‐generation (5G) networks deal with high‐frequency data rates, ultra‐low latency, more reliability, massive network capacity, more availability, and a more uniform user experience. To validate the high‐frequency rates, 5G networks engage beam searching operation. By adopting a beam searching state between the short and long sleep, one can reduce the system's delay. The energy consumption of user equipment (UE) in 5G networks is much higher than in the 4G networks. To reduce the energy consumption and increase the energy saving in UE, Long‐Term Evolution (LTE)‐5G networks adopt the discontinuous reception (DRX) scheme with a fixed number of short sleep. LTE‐DRX without beam search operation (i.e., beam alignment) cannot work in 5G networks. Hence, keeping this scenario in mind, we have modeled a new modified directional discontinuous reception (MD‐DRX) mechanism for LTE‐5G networks. The MD‐DRX mechanism captures the behavior of a beam searching, an inactive, an active, a long sleep, an ON, and a short sleep states. The short sleep state consists of a maximum M short sleep. To get the optimal energy saving and energy consumption (i.e., energy efficiency) from the MD‐DRX mechanism, it is required to check the system's throughput. The trade‐off between energy saving/energy consumption and throughput will provide the system's optimal energy saving and optimal energy consumption. In this paper, we have obtained the system's optimal energy saving and throughput by optimizing the maximum short sleep and short sleep duration. To get the energy efficiency for LTE‐5G networks, the trade‐off between average energy consumption/energy saving and throughput is shown. [ABSTRACT FROM AUTHOR]

Using a catalyst-free one-pot polycondensation approach, a new donor–acceptor (D–A) based porous polyimide (PeTt–POP) photocatalyst was developed. PeTt–POP produced CH4 (125.63 ppm g−1 in 6 h) from CO2 under visible light irradiation in the gas–solid mode without the use of co-catalysts or sacrificial agents. The progress of the reaction and the corresponding intermediate species involved in the CO2 reduction were identified by operando DRIFTS experiments, from which a plausible reaction mechanism was proposed. [ABSTRACT FROM AUTHOR]

Hydrothermal synthesis of a ZSM-5/MCM-41 composite has been carried out from pre-synthesized ZSM-5 zeolite as a silica source and CTAB as a template. The ZSM-5/MCM-41 composite materials were further loaded with varying wt% of cobalt with respect to ZSM-5 by an in situ modification method using cobaltous nitrate as a metal source. Detailed analysis of the synthesized materials was performed using different characterization techniques such as PXRD, FT-IR, TGA, UV-Vis DRS, N2 adsorption–desorption and SEM-EDX. The catalytic activity of the synthesized materials for liquid phase oxidation of diphenylmethane was investigated in the presence of 70% TBHP as an oxidant where benzophenone was obtained as a major product. The effects of various reaction parameters were studied to perceive the conversion of diphenylmethane and enhance the selectivity towards benzophenone. [ABSTRACT FROM AUTHOR]

Functionalization of synthesized mesoporous MCM‐48 was performed using phosphoric acid via post synthesis modification method and characterized using different analytical techniques. The acidic character of the phosphoric acid modified material was enhanced compared to parent MCM‐48 as predicted from the Ammonia‐Temperature Programmed Desorption (NH3‐TPD) analysis. The catalytic activity of the synthesized materials was investigated for the synthesis of 2‐amino‐4H‐chromene via one pot three component reaction using aldehyde, malononitrile and dimedone using ethanol as solvent at 60 °C. Moderate to good yields of the desired products were obtained with substituted benzaldehyde under the optimized reaction condition. Moreover, reusability of the catalyst was also demonstrated upto five catalytic cycles with minimal loss in catalytic activity. [ABSTRACT FROM AUTHOR]

Using a catalyst-free one-pot polycondensation approach, a new donor-acceptor (D-A) based porous polyimide (PeTt-POP) photocatalyst was developed. PeTt-POP produced CH 4 (125.63 ppm g -1 in 6 h) from CO 2 under visible light irradiation in the gas-solid mode without the use of co-catalysts or sacrificial agents. The progress of the reaction and the corresponding intermediate species involved in the CO 2 reduction were identified by operando DRIFTS experiments, from which a plausible reaction mechanism was proposed.