Long Cycle‐Life Ca Batteries with Poly(anthraquinonylsulfide) Cathodes and Ca−Sn Alloy Anodes

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Long Cycle-Life Ca Batteries with Poly(anthraquinonylsulfide) Cathodes and Ca−Sn Alloy Anodes

Organic electrode: 1,5-poly(anthraquinonylsulfide) (PAQS) is evaluated as cathode material for calcium batteries. It is demonstrated that the practical performance of the PAQS cathode is governed by the employed anode. Replacing the Ca metal anode with a calcium-tin (Ca x Sn) alloy anode gave rise to significantly increased cycle life. With the as-prepared Ca x Sn anode, the PAQS cathode could be cycled at 0.5C (1C=226 mAh g−1) for 1000 cycles with a capacity retention of 45 mAh g−1.


Abstract

Calcium (Ca) batteries are attractive post-lithium battery technologies, due to their potential to provide high-voltage and high-energy systems in a sustainable manner. We investigated herein 1,5-poly(anthraquinonylsulfide) (PAQS) for Ca-ion storage with calcium tetrakis(hexafluoroisopropyloxy)borate Ca[B(hfip)4]2 [hfip=OCH(CF3)2] electrolytes. It is demonstrated that PAQS could be synthesized in a cost-effective approach and be processed environmentally friendly into the electrodes. The PAQS cathodes could provide 94 mAh g−1 capacity at 2.2 V vs. Ca at 0.5C (1C=225 mAh g−1). However, cycling of the cells was severely hindered due to the fast degradation of the metal anode. Replacing the Ca metal anode with a calcium-tin (Ca−Sn) alloy anode, the PAQS cathodes exhibited long cycling performance (45 mAh g−1 at 0.5C after 1000 cycles) and superior rate capability (52 mAh g−1 at 5C). This is mainly ascribed to the flexible structure of PAQS and good compatibility of the alloy anodes with the electrolyte solutions, which allow reversible quinone carbonyl redox chemistry in the Ca battery systems. The promising properties of PAQS indicate that further exploration of the organic cathode materials could be a feasible direction towards green Ca batteries.

Deep Eutectic Solvents: An Eco‐friendly Design for Drug Engineering

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Deep Eutectic Solvents: An Eco-friendly Design for Drug Engineering

Deep eutectic solvents (DESs) appeared as an alternative to harmful organic solvents. This review presents a framework for understanding the development process of DESs, starting from the main parameters for judiciously selecting the DES components, then highlighting the methods of preparation and characterization, and ending with explaining the role of DESs in designing drug delivery systems.


Abstract

In the spirit of circular economy and sustainable chemistry, the use of environmentally friendly chemical products in pharmacy has become a hot topic. In recent years, organic solvents have been the subject of a great range of restriction policies due to their harmful effects on the environment and toxicity to human health. In parallel, deep eutectic solvents (DESs) have emerged as suitable greener solvents with beneficial environmental impacts and a rich palette of physicochemical advantages related to their low cost and biocompatibility. Additionally, DESs can enable remarkable solubilizing effect for several active pharmaceutical ingredients (APIs), thus forming therapeutic DESs (TheDESs). In this work, special attention is paid to DESs, presenting a precise definition, classification, methods of preparation, and characterization. A description of natural DESs (NaDESs), i. e., eutectic solvents present in natural sources, is also reported. Moreover, the present review article is the first one to detail the different approaches for judiciously selecting the constituents of DESs in order to minimize the number of experiments. The role of DESs in the biomedical and pharmaceutical sectors and their impact on the development of successful therapies are also discussed.

Tuning the Interfaces of ZnO/ZnCr2O4 Derived from Layered‐Double‐Hydroxide Precursors to Advance Nitrogen Photofixation

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Tuning the Interfaces of ZnO/ZnCr2O4 Derived from Layered-Double-Hydroxide Precursors to Advance Nitrogen Photofixation

Advanced ZnO/ZnCr2O4 photocatalysts derived from ZnCr-layered double hydroxide (ZnCr-LDH) precursors are successfully synthetized by a simple thermal process. The optimized ZnO/ZnCr2O4 exhibit a considerable ammonia photosynthesis rate of 31.7 μmol g−1 h−1 in pure water, with the origin of the high activity being derived from the high-efficiency carrier separation due to the abundant interfaces.


Abstract

Drawing inspiration from the enzyme nitrogenase in nature, researchers are increasingly delving into semiconductor photocatalytic nitrogen fixation due to its similar surface catalytic processes. Herein, we reported a facile and efficient approach to achieving the regulation of ZnO/ZnCr2O4 photocatalysts with ZnCr-layered double hydroxide (ZnCr-LDH) as precursors. By optimizing the composition ratio of Zn/Cr in ZnCr-LDH to tune interfaces, we can achieve an enhanced nitrogen photofixation performance (an ammonia evolution rate of 31.7 μmol g−1 h−1 using pure water as a proton source) under ambient conditions. Further, photo-electrochemical measurements and transient surface photovoltage spectroscopy revealed that the enhanced photocatalytic activity can be ascribed to the effective carrier separation efficiency, originating from the abundant composite interfaces. This work further demonstrated a promising and viable strategy for the synthesis of nanocomposite photocatalysts for nitrogen photofixation and other challenging photocatalytic reactions.

Physicochemical Properties and Applications of Deep Eutectic Solvents for CO2 Capture

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Physicochemical Properties and Applications of Deep Eutectic Solvents for CO2 Capture

CO2 separation is critical for energy savings and CO2 emission reduction. Deep eutectic solvents (DESs) as ionic liquids (ILs) analogues exhibit significant potential in CO2 capture with favorable solvent properties and are considered economical alternatives to conventional ILs. The state-of-the-art of physicochemical properties of DESs related to their influence on CO2 absorption mechanisms is discussed.


Abstract

Rising anthropogenic greenhouse gas concentrations, notably CO2 emissions, have led to environmental issues that affect both humans and ecosystems. CO2 separation makes it easier to reduce energy use and CO2 emissions, both of which are essential for combating the concern of global warming. The use of ionic liquids (ILs) as CO2 capture solvents is recommended. However, the high viscosity, toxicity, cost, and poor biodegradability of ILs limit their large-scale application. In recent years, deep eutectic solvents (DESs) have been created with improved CO2 separation efficiency, lower preparation costs, and less negative environmental impact. The state-of-the-art of the physicochemical properties of DESs in connection to their influence on CO2 capture processes and the studies of CO2 solubility in DESs are discussed. The absorption mechanism of CO2 in DESs and the effect of temperatures, pressures, and hydrogen bond donors (HBDs) on the solubility of CO2 in DESs are overviewed and analyzed, and future research directions on this topic are suggested.

Modular Synthesis of Fluoro‐Substituted Furan Compounds via Controllable Fluorination of Biomass‐Based 5‐HMF and Its Derivatives

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5-Hydroxymethylfurfural (5-HMF) is regarded as one of the most promising platform feedstocks for producing valuable chemicals, fuels, and materials. In this study, we present a controllable fluorination technique for biomass-based 5-HMF and its oxygenated derivatives. This technique allows us to synthesize mono-fluoromethyl, difluoromethyl, and acylfluoro-substituted furan compounds by adjusting experimental conditions such as different fluorine sources and mole ratio. To gain a deeper understanding the reactivity order, we conducted intermolecular and  intramolecular competition experiments. The results revealed that the hydroxyl group exhibited the highest reactivity, followed by the aldehyde group. This finding provides important theoretical support and opens up the possibility of selective fluorination. The reaction offers several advantages, including mild conditions, no need for inert gas protection, and easy operation. Furthermore, the fluoro-substituted furan compounds can be further transformed for the preparation of drug analogs, offering a new route for the high-value utilization of biomass molecules.

Bound state calculations for Hulthén–Hellmann type potential by improved asymptotic iteration method

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Bound state calculations for Hulthén–Hellmann type potential by improved asymptotic iteration method

Coulomb and Hulthén–Hellmann potential versus r for A = 0.002, B = 2, C = 1, α = 0.001


Abstract

In this study, some nonrelativistic energy eigenvalues of Hulthén–Hellmann type interaction were calculated using the improved asymptotic iteration method (improved AIM) by applying the Greene–Aldrich approach for the inverse square term of the potential. Calculations have also been made for some special cases of the Hulthén–Hellmann potential. It is seen that the results obtained are in excellent agreement with those previously obtained from other methods.

Exposure of Lemna minor (Common Duckweed) to Mixtures of Uranium and Perfluorooctanoic Acid (PFOA)

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Abstract

A variety of processes, both natural and anthropogenic, can have a negative impact on surface waters, which in turn can be detrimental to human and environmental health. Few studies have considered the ecotoxicological impacts of concurrently occurring contaminants, and that is particularly true for mixtures that include contaminants of emerging concern (CEC). Motivated by this knowledge gap, the present study considers the potential ecotoxicity of environmentally relevant contaminants in the representative aquatic plant Lemna minor (common duckweed), a model organism. More specifically, biological effects associated with exposure of L. minor to a ubiquitous radionuclide (uranium [U]) and a fluorinated organic compound (perfluorooctanoic acid [PFOA], considered a CEC), alone and in combination, were monitored under controlled laboratory conditions. Lemna minor was grown for 5 days in small, aerated containers. Each treatment consisted of four replicates with seven plants each. Treatments were 0, 0.3, and 3 ppb PFOA; 0, 0.5, and 5 ppb U; and combinations of these. Plants were observed daily for frond number and signs of chlorosis and necrosis. Other biological endpoints examined at the conclusion of the experiment were chlorophyll content and antioxidant capacity. In single-exposure experiments, a slight stimulatory effect was observed on frond number at 0.3 ppb PFOA, whereas both concentrations of U had a detrimental effect on frond number. In the dual-exposure experiment, the combinations with 5 ppb U also had a detrimental effect on frond number. Results for chlorophyll content and antioxidant capacity were less meaningful, suggesting that environmentally relevant concentrations of PFOA and U have only subtle effects on L. minor growth and health status. Environ Toxicol Chem 2023;00:1–10. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

The Use of Multiple Biomarkers to Assess the Health of Anuran Amphibians in the Brazilian Cerrado Savanna: An Ecotoxicological Approach

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The Use of Multiple Biomarkers to Assess the Health of Anuran Amphibians in the Brazilian Cerrado Savanna: An Ecotoxicological Approach

A worrisome look into aquatic life: Anuran egg masses in Goiás State reveal toxic and DNA damage.


Abstract

Changes in the natural landscape and the indiscriminate use of pesticides can have a major impact on aquatic environments and have contributed to the worldwide decline of amphibian populations. In the present study, we sampled tadpoles of three anuran amphibians (Boana albopunctata, Physalaemus cuvieri, and Dendropsophus minutus) from ponds in six different agricultural landscapes of the Brazilian Cerrado savanna and evaluated whether and to what extent genotoxic and mutagenic damage was related to land use (the amount of forest and agricultural remnants, and related physicochemical factors) and the presence of pesticides in the water of the study ponds. We also evaluated the hepatotoxicity in P. cuvieri, which was the most abundant species at five of the six sampling points. Clomazone and atrazine were the most common pesticides found in the ponds. The B. albopunctata and P. cuvieri tadpoles presented similar patterns of DNA damage among the sampling points. The least DNA damage was found in the D. minutus tadpoles, although this species was present in only one of the study ponds. More binucleated and anucleated cells were observed in B. albopunctata, but there was no significant variation among species in terms of the number of micronuclei or other erythrocytic nuclear abnormalities. Land use and physicochemical factors did not explain the variation in the DNA damage observed in the three anurans. The hepatotoxicity analyses of P. cuvieri revealed the presence of a series of alterations, including the enlargement of the sinusoids, vacuolization of the hepatocytes, the infiltration of inflammatory cells, hepatic steatosis, and dilation of the blood vessels. The interaction between physicochemical factors and the biomarkers analyzed in the present study is complex. In particular, it will be important to better elucidate which factors are contributing, either directly or indirectly, to the decline of anuran amphibian populations, especially in threatened biomes, such as the Brazilian Cerrado. In this case, we would encourage further in situ studies that assess the ecotoxicology of the landscape, together with the systematic monitoring of aquatic environments, to guarantee the long-term integrity of amphibian populations, and those of other organisms that play an essential functional role in the ecosystem. Environ Toxicol Chem 2023;00:1–18. © 2023 SETAC

Maternal Transfer and Effects of Selenium on Early Life Stage Development of Redside Shiner (Richardsonius balteatus)

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Abstract

Maternal transfer of selenium (Se) to developing fish eggs during vitellogenesis can cause larval deformity and mortality. Previous studies have shown wide variation among fish species in both the magnitude of maternal transfer (exposure) and the egg Se concentration causing effects (sensitivity). We studied maternal transfer and effects of Se on early life stage development, survival, and growth of redside shiner (Richardsonius balteatus), a small-bodied cyprinid that has been reported to have relatively high ovary:muscle Se concentration ratios. Gametes were collected from lentic areas in southeast British Columbia (Canada) with a range of dietary Se concentrations related to weathering of waste rock from coal mining. Eggs were fertilized and reared in the laboratory from hatch to the onset of exogenous feeding. Larvae were assessed for survival, length, weight, Se-characteristic deformities, and edema. Eggs from a total of 56 females were collected, with egg Se concentrations from 0.7 to 28 mg/kg dry weight. Maternal transfer varied among sites, with egg:muscle Se concentration ratios ranging from <1 to >4. We also found that sampling residual ovaries can overestimate Se concentrations in ripe eggs by up to a factor of 5.7. A correlation between larval weight and egg Se concentration was identified, although the relationship was weak (r 2 < 0.1) and appeared to be a site effect. No other relationships were observed between larval endpoints and egg Se concentrations up to the highest concentration tested, indicating that the effects threshold for this species may be >28 mg/kg dry weight in eggs. These data indicate that redside shiner is less sensitive to maternally transferred Se than most other tested fish species. Environ Toxicol Chem 2023;00:1–8. © 2023 SETAC

Photothermally Enhanced Dual Enzyme‐mimic Activity of Gold‐Palladium Hybrid Nanozyme for Cancer Therapy

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Photothermally Enhanced Dual Enzyme-mimic Activity of Gold-Palladium Hybrid Nanozyme for Cancer Therapy

The dumbbell-like Au-Pd bimetallic nanomaterials (Au NRs-Pd@HA) were obtained by reducing palladium on gold nanorods with ascorbic acid (AA) and further modified with hyaluronic acid (HA). Au NRs-Pd@HA can induce catalytic conversion of glucose to generate H2O2 efficiently, and subsequently undergo cascade reaction to produce abundant ·OH radicals, exhibiting peroxidase-like (POD-like) and glucose oxidase-like (GOD-like) capabilities. The generated ·OH was a key factor for tumor ablation. Meanwhile, Au NRs-Pd@HA exhibit good photothermal performance under 808 nm irradiation, in favor of photothermal therapy (PTT). Especially, the POD-like and GOD-like activities were significantly enhanced due to the photothermal effect. The synergistic PTT and photothermal-enhanced nanozymes with cascade catalytic effect enabled efficient and safe cancer therapy.


Comprehensive Summary

Based on characteristics of the tumor microenvironment (TME), including acidity, hypoxia, inflammation and hydrogen peroxide overload, combined with emerging nanotechnologies, designing nanoplatforms with TME specificity/responsiveness for tumor treatment is a promising nanotherapeutic strategy. In this work, a multifunctional gold-palladium bimetallic cascade nanozyme was constructed for effective photothermal-enhanced cascade catalyzed synergistic therapy of tumors. The dumbbell-like Au-Pd bimetallic nanomaterial (Au NRs-Pd@HA) was obtained by reducing palladium on gold nanorods with ascorbic acid (AA) and further modified with hyaluronic acid (HA). The introduction of HA brings biocompatibility and targeting properties. The zebrafish embryos model showed that Au NRs-Pd@HA had good biocompatibility and low biotoxicity. Au NRs-Pd@HA can induce catalytic conversion of glucose to generate H2O2 efficiently, and subsequently undergo cascade reaction to produce abundant ·OH radicals, exhibiting peroxidase-like (POD-like) and glucose oxidase-like (GOD-like) capabilities. The generated ·OH was a key factor for tumor ablation. Meanwhile, Au NRs-Pd@HA exhibits good photothermal performance under 808 nm irradiation, in favor of photothermal therapy (PTT). Especially, the POD-like and GOD-like activities were significantly enhanced due to the photothermal effect. The synergistic PTT and photothermal-enhanced nanozymes with cascade catalytic effect enabled efficient and safe cancer therapy.