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The impact of contaminants on Copepod sp. and its molecular response is least explored, despite their abundance and dominance among invertebrates in aquatic environments. In the present investigation, Dioithona rigida, a cyclopoid zooplankton, was treated with selenium nanoparticles (SeNPs) to determine the associated biochemical changes, and the chronic exposure effects were recorded using transcriptomic analysis. It was found that, SeNPs were acutely toxic with a lethal dose 50% of 140.9 mg/L. The de novo assembled transcriptome of the copepod comprised 81,814 transcripts, which underwent subsequent annotations to biological processes (23,378), cellular components (21,414), and molecular functions (31,015). Comparison of the expressed transcripts against the treated sample showed that a total of 186 transcript genes were differentially expressed among the D. rigida treatments (control and SeNPs). The significant downregulated genes are coding for DNA repair, DNA-templated DNA replication, DNA integration, oxidoreductase activity and transmembrane transport. Similarly, significant upregulations were observed in protein phosphatase binding and regulation of membrane repolarization. Understanding the impact of SeNPs on copepods is crucial not only for aquatic ecosystem health but also for human health, as these organisms play a key role in marine food webs, ultimately affecting the fish consumed by humans. By elucidating the molecular responses and potential toxicological effects of SeNPs, this study provides key insights for risk assessments and regulatory policies, ensuring the safety of seafood and protecting human health from the unintended consequences of nanoparticle pollution. IMPACT STATEMENT: The toxicity analysis in Dioithona rigida is the first of its kind as a copepod model for analysis on dietary fixation of metal toxicity at the trophic level. Since this copepod is a major zooplankton fed by fish and crustacean larvae in marine ecosystems, the toxicity analysis on this copepod will give us more insights of the trophic-level food transfer. As far as our knowledge, this is the first study that opted to construct the de novo transcriptomic pipeline for this copepod, treated with selenium nanoparticles. The effectiveness of this work may be further extrapolated to assess the effect of other metal nanoparticles in this model organism. Although the selenium toxicity in marine ecosystem is an established sector, through our combined approach of biochemical analysis and omics approach, the solid framework and comprehensive insight of the selenium toxicity in reproductive fitness and molecular changes has been studied. This study chose to seek a reliable alternative in the sense of new copepod model and omics approach to analyse the relevant metal nanoparticle toxicity in the marine ecosystem. [ABSTRACT FROM AUTHOR]

A series of porous organic polymers based on a singlet oxygen generating oxoporphyinogen ('OxP') has been successfully prepared from a pseudotetrahedral OxP-tetraamine precursor (OxP(4-NH2Bn)4) by its reaction with tetracarboxylic acid dianhydrides under suitable conditions. Of the compounds studied, those containing naphthalene (OxP-N) and perylene (OxP-P) spacers, respectively, have large surface areas (~530 m2 g−1). On the other hand, the derivative with a simple benzene spacer (OxP-B) exhibits the best 1O2 generating capability. Although the starting OxP-tetraamine precursor is a poor 1O2 generator, its incorporation into OxP POPs leads to a significant enhancement of 1O2 productivity, which is largely due to the transformation of NH2 groups to electron-withdrawing diimides. Overall 1O2 production efficacy of OxP-POPs under irradiation by visible light is significantly improved over the common reference material PCN-222. All the materials OxP-B, OxP-N and OxP-P promote oxidation of thioanisole involving conversion of ambient triplet state oxygen to singlet oxygen under visible light irradiation and its reaction with the sulfide. Although the reaction rate of the oxidation promoted by OxP POPs is generally lower than for conventional materials (such as PCN-222) or previously studied OxP derivatives, undesired overoxidation of the substrate to methyl phenyl sulfone is suppressed. For organic sulfides, selectivity of oxidation is especially important for detoxification of mustard gas (bis(2-chloroethyl)sulfide) or similarly toxic compounds since controlled oxidation leads to the low toxicity bis(2-chloroethyl)sulfoxide while overoxidation leads to intoxification (since bis(2-chloroethyl)sulfone presents greater toxicity to humans than the sulfide substrate). Therefore, OxP POPs capable of promoting selective oxidation of sulfides to sulfoxides have excellent potential to be used as mild and selective detoxification agents. IMPACT STATEMENT: Oxoporphyrinogen (OxP) is a unique chromophore compound in that it is intrinsically de-aggregated allowing large quantum yields of singlet oxygen generation. Due to its structure, OxP is also an ideal building block for porous systems. In this work, we describe the first incorporation of OxP in highly stable microporous polymers strongly enhanced singlet oxygen generation for selective oxidation of organic sulfides to sulfoxides (as a model reaction) under heterogeneous conditions. The novelty of this work lies in the high stability and easy recovery of the materials, the synergetic enhancement of singlet oxygen generation in the polymers over the starting OxP, and the excellent selectivity for the oxidation reaction. [ABSTRACT FROM AUTHOR]

Energy storage in electrochemical hybrid capacitors involves fast faradaic reactions such as an intercalation, or redox process occurring at a solid electrode surface at an appropriate potential. Hybrid sodium‐ion electrochemical capacitors bring the advantages of both the high specific power of capacitors and the high specific energy of batteries, where activated carbon serves as a critical electrode material. The charge storage in activated carbon arises from an adsorption process rather than a redox reaction and is an electrical double‐layer capacitor. Advanced carbon materials with interconnecting porous structures possessing high surface area and high conductivity are the prerequisites 1128to qualify for efficient energy storage. Herein, we have demonstrated that a porous honeycomb structure activated carbon derived from Australian hemp hurd (Cannabis sativa L.) in aqueous Na2SO4 electrolyte showed a specific capacitance of 240 F/g at 1 A/g. The mass ratio of biochar to KOH during the chemical activation associated with the synthesis temperature influences the change in morphologies, and distribution of pore sizes on the adsorption of ions. At higher synthesis temperatures, the tubular form of the honeycomb starts to disintegrate. The hybrid sodium‐ion device employing hemp‐derived activated carbon (HAC) coupled with electrolytic manganese dioxide (EMD) in an aqueous Na2SO4 electrolyte showed a specific capacitance of 95 F/g at 1 A/g having a capacitance retention of 90 %. The hybrid device (HAC||EMD) can possess excellent electrochemical performance metrics, having a high energy density of 38 Wh/kg at a power density of 761 W/kg. Overall, this study provides insights into the influence of the activation temperature and the KOH impregnation ratio on morphology, porosity distribution, and the activated carbon's electrochemical properties with faster kinetics. The high cell voltage for the device is devoted to the EMD electrode. [ABSTRACT FROM AUTHOR]

Aqueous sodium (Na+) ion storage systems face challenges due to sluggish adsorption and diffusion of Na+ ions with larger size, hindering their potential for stationary applications. This issue is addressed by evolving the interfacial electronic coupling in atomically thin 2D WO3/WSe2 heterostructure for efficient Na+ ion storage. Density functional theory (DFT) analysis elucidates the superior charge storage capability for the WO3/WSe2 heterostructure facilitated by the charge transfer from the WO3 – WSe2 (002). The charge transfer from the W‐5d and O‐2p orbitals of WO3 to the valence W‐5d and Se‐4p orbitals of the WSe2 (002) surface boosts the electronic conductivity. As a result, the WO3/WSe2 electrode demonstrates exceptional Na+ ion storage, with a specific capacitance of 378.1 F g−1 at 1 A g−1, excellent rate capability, and long‐lasting cycling durability. The full cell comprising WO3/WSe2 as the negative and MnSe/MnSe2 as the positive electrode achieved a peak energy density of 82.1 Wh kg−1 at a power density of 1873.5 W kg−1, along with high rate capability and long‐cycle durability. Insights gained from this study pave the technique for the rational design and optimization of the interfacial electronic features in 2D heterostructures for next‐generation energy storage devices with enhanced performance and stability. [ABSTRACT FROM AUTHOR]

We report an efficient ORR electrocatalyst containing cobalt single atom and cobalt nanoparticle active sites embedded in a porous nitrogen-doped graphitic carbon network. The robust electrocatalyst exhibits superior electrochemical ORR activity with onset and half-wave potentials of 0.96 V and 0.87 V (vs. reversible hydrogen electrode), respectively, and has excellent durability and methanol tolerance further enhancing the potential of this system for practical applications. [ABSTRACT FROM AUTHOR]

The recognition of the importance of nanostructures is mainly due to the development of nanotechnology. For further developments in materials sciences, a concept that integrates nanotechnology with material chemistry to fabricate functional materials has to be proposed. Nanoarchitectonics will carry out this task. In nanoarchitectonics, we architect functional material systems from nano-units (atoms, molecules, nanomaterials). The methodology is not specific to any particular material or application. It covers a wide range. Therefore, nanoarchitectonics can be thought of as the method for everything in materials science. As typical demonstrations for usages of nanoarchitectonics, this review paper presents our work on nanoarchitectonics for supercapacitors. We divide it into two categories with different approaches. The first is the development of carbon materials as supercapacitor electrode materials from biomass. The second category is preparing carbon materials using structures created by supramolecular assembly of fullerenes such as C60 and C70. By presenting examples using opposite starting materials, a complex natural material, and an ultimately simple molecule, we will demonstrate the versatility and breadth of possibilities of this approach. [ABSTRACT FROM AUTHOR]