Iodine Species Research Articles

ZIF-67/melamine-derived cobalt encapsulated in N-doped CNTs for periodate activation toward tetracycline degradation

Advance oxidation processes (AOPs) based on periodate (PI) offer new methods for removing pollutants, but the activation of PI by carbon nanotubes and its composites has been rarely reported. In this study, N-doped carbon nanotubes encapsulated cobalt (Co@NCNTs) was synthesized through melamine assisted ZIF–67 pyrolysis, and it was used to activate PI for the tetracycline (TC) degradation. Effects of experimental parameters including catalyst dosage, periodate concentration, initial pH, and temperature were investigated. The results show that this system exhibited excellent activation performance under wide pH (4–10) with a low reaction activation energy (Ea = 8.874 kJ/mol). Radical quenching experiments manifested that iodate radical (IO3) played a main role in the TC elimination, followed by superoxide radical (O2−), singlet oxygen (1O2), and hydroxyl radicals (OH). Additionally, it is found that IO4− is not converted into toxic iodine species (I2, HOI) but nontoxic iodate (IO3−), indicating that no secondary pollution occurred. Finally, possible TC degradation pathways were proposed based on the results of high-performance liquid chromatography mass spectrometry (HPLC-MS) analysis. This article provides a novel approach for the activation PI to remove pollutants and a theoretical support for practical applications.

Redox mediator enabling fast reaction kinetics and high utilization of iodine in aqueous iodine redox flow battery

Aqueous iodine redox flow batteries (AIRFBs) have been identified as a promising technology for large-scale energy storage. However, practical capacity of AIRFBs is limited by the relatively low utilization of iodine caused by the low reaction kinetics. Here, we report an electrode modified by cobalt hexacyanoferrate (CoHCF), which supports a redox-mediating process developing alternative redox reaction pathways of iodine with reduced redox activation energies. Contributed by the strong adsorption of iodine by CoHCF, redox reaction kinetics of iodine species is accelerated, and the utilization of iodine in batteries is increased. Applying the CoHCF modified carbon felt as cathode electrode, the constructed zinc-iodine redox flow battery exhibits a high iodine utilization reaching 95.59% of the theoretical capacity at a current density of 20 mA cm−2, which enhances 139.89% comparing to the battery without electrode modification. The redox mediator-based electrode enabling fast reaction kinetics and high utilization of iodine species offers a promising strategy enhancing the battery performance thereby advancing the development of AIRFBs.

Enhanced degradation of sulfathiazole by ionizing radiation activated persulfate and periodate: Performances and mechanisms

Ionizing radiation has attracted significant interests in water purifying. However, it suffers from poor mineralization performance during the decontamination of organic micropollutants such as antibiotics. Herein, the radiolytic degradation of sulfathiazole (STZ) by gamma radiation was investigated. STZ could be completely degraded at 2.0 kGy absorbed dose but TOC removal efficiency was only 22.62 %. Quenching experiments demonstrated that •OH was the main reactive species. Toxicity assessment and phytotoxicity experiments indicated that gamma radiation can comprehensively decrease the toxicity of STZ. Significant enhancements of degradation and mineralization were observed in gamma/persulfate (Gamma/PS) and gamma/periodate (Gamma/PI) processes. The rate constant (k) increased by 1.08 times and TOC removal efficiency increased by 2.01 times with PS addition (1 mM). The k value enhanced by 4.05 times and TOC removal ratio enhanced by 2.66 times with the presence of PI (1 mM). Mechanistic investigation indicated that 1O2 played a major role in STZ degradation in the Gamma/PS and Gamma/PI systems. PI was almost completely transferred into the nontoxic iodate (IO3-), and no toxic reactive iodine species were produced in the Gamma/PI process. Moreover, Gamma/PS and Gamma/PI systems showed a broad-spectrum ability to remove a series of antibiotics. The removal performances and the costs of these systems were competitive compared with other advanced oxidation processes for antibiotics elimination. This study supplied an efficient and sustainable choice for the degradation of antibiotics, and clarified the intrinsic reaction mechanisms in the ionizing radiation-activated PS and PI systems.

Integrated Trap‐Adsorption‐Catalysis Nanoreactor for Shuttle‐Free Aqueous Zinc‐Iodide Batteries

AbstractAqueous zinc‐iodine batteries (AZIBs) are very promising energy storage systems owing to their safety, reliability, large specific capacity, and durable lifespan. However, the sluggish iodine redox kinetics and polyiodides shuttle effect severely impedes their wider application. Addressing these challenges, this study develops a new multifunctional nanoreactor integrating “Trap‐Adsorption‐Catalysis” advantages, which features the electron‐rich cobalt (Co) nanoparticles embedded in porous activated carbon (AC). Benefiting from the integrated advantages of trap‐adsorption‐catalysis behavior in the nanoreactor, this novel system enables the fast iodine (I2/I‐) conversion by enhanced kinetics, achieving high utilization of iodine and corrosion‐free zinc anode without producing polyiodides. In situ UV–vis spectroscopy, theoretical calculation combined with electrochemical analysis demonstrates that the Co@AC nanoreactor reduces the adsorption energy and conversion energy barrier of iodine species, and accelerates the conversion of polyiodides to improve the electrochemical properties. Notably, the Co@AC/I2 cathode delivers an outstanding rate capability of 221.1 and 102.5 mA h g−1 at the current density of 0.5 and 25C with high CE over >99.9%, respectively, low self‐discharge rate over 96h and high energy efficiency (EE) of 89.2% at 5.0C over 1000 cycles. These self‐discharge and EE properties are the best among AZIBs systems with Co‐based host cathodes ever reported.

Degradation of emerging contaminants in synthetic hydrolyzed urine by UV/peracetic acid: Free radical chemistry, and toxicity analysis

The ecological impact of emerging contaminants (ECs) in aquatic environments has raised concerns, particularly with regards to urine as a significant source of such contaminants in wastewater. The current investigation used the UV/Peracetic Acid (UV/PAA) processes, an innovative advanced oxidation technology, to effectively separate two emerging pollutants from urine at its source, namely, ciprofloxacin (CIP) and bisphenol A(BPA). The research findings demonstrate that the presence of the majority of characteristic ions has minimal impact on the degradation of ECs. However, in synthetic hydrolyzed urine, only NH4+ inhibits the degradation of two types of ECs, with a more pronounced effect observed on CIP degradation compared to BPA.The impact of halogen ions, specifically Cl− and I−, on the degradation of CIP in synthetic hydrolyzed urine was a complex phenomenon. When these two halogen ions are present individually, the generation of reactive halogen species (RHS) within the system enhances the degradation of CIP. However, when both types of ions coexist, the formation of diatomic radical species partially inhibits degradation. In terms of BPA degradation, while the production of reactive chlorine species (RCS) to some extent hinders the reaction rate, the generation of reactive iodine species (RIS) promotes the overall process. CIP undergoes fragmentation of the piperazine and quinoline rings, decarboxylation, defluorination reactions, as well as substitution reactions, leading to the formation of products with simplified structures. The degradation of BPA occurs gradually through hydroxyl and halogen substitution as well as isopropyl cleavage. The preliminary toxicity analysis confirmed that the presence of halogen ions in urine resulted in the formation of halogenated products in two types of ECs, albeit with an overall reduction in toxicity. The UV/PAA processes was considered to be an effective and relatively safe approach for the separation of ECs in urine.

Effect of iodine species on biofortification of iodine in cabbage plants cultivated in hydroponic cultures

Iodine is an essential trace element in the human diet because it is involved in the synthesis of thyroid hormones. Iodine deficiency affects over 2.2 billion people worldwide, making it a significant challenge to find plant-based sources of iodine that meet the recommended daily intake of this trace element. In this study, cabbage plants were cultivated in a hydroponic system containing iodine at concentrations ranging from 0.01 to 1.0 mg/L in the form of potassium iodide or potassium iodate. During the experiments, plant physiological parameters, biomass production, and concentration changes of iodine and selected microelements in different plant parts were investigated. In addition, the oxidation state of the accumulated iodine in root samples was determined. Results showed that iodine addition had no effect on photosynthetic efficiency and chlorophyll content. Iodide treatment did not considerably stimulate biomass production but iodate treatment increased it at concentrations less than 0.5 mg/L. Increasing iodine concentrations in the nutrient solutions increased iodine content in all plant parts; however, the iodide treatment was 2–7 times more efficient than the iodate treatment. It was concluded, that iodide addition was more favourable on the target element accumulation, however, it should be highlighted that application of this chemical form in nutrient solution decreased the concetrations of selected micoelement concentration comparing with the control plants. It was established that iodate was reduced to iodide during its uptake in cabbage roots, which means that independently from the oxidation number of iodine (+ 5, − 1) applied in the nutrient solutions, the reduced form of target element was transported to the aerial and edible tissues.

Iodine Clusters in the Atmosphere I: Computational Benchmark and Dimer Formation of Oxyacids and Oxides.

The contribution of iodine-containing compounds to atmospheric new particle formation is still not fully understood, but iodic acid and iodous acid are thought to be significant contributors. While several quantum chemical studies have been carried out on clusters containing iodine, there is no comprehensive benchmark study quantifying the accuracy of the applied methods. Here, we present the first study in a series that investigate the role of iodine species in atmospheric cluster formation. In this work, we have studied the iodic acid, iodous acid, iodine tetroxide, and iodine pentoxide monomers and their dimers formed with common atmospheric precursors. We have tested the accuracy of commonly applied methods for calculating the geometry of the monomers, thermal corrections of monomers and dimers, the contribution of spin-orbit coupling to monomers and dimers, and finally, the accuracy of the electronic energy correction calculated at different levels of theory. We find that optimizing the structures either at the ωB97X-D3BJ/aug-cc-pVTZ-PP or the M06-2X/aug-cc-pVTZ-PP level achieves the best thermal contribution to the binding free energy. The electronic energy correction can then be calculated at the ZORA-DLPNO-CCSD(T0) level with the SARC-ZORA-TZVPP basis for iodine and ma-ZORA-def2-TZVPP for non-iodine atoms. We applied this methodology to calculate the binding free energies of iodine-containing dimer clusters, where we confirm the qualitative trends observed in previous studies. However, we identify that previous studies overestimate the stability of the clusters by several kcal/mol due to the neglect of relativistic effects. This means that their contributions to the currently studied nucleation pathways of new particle formation are likely overestimated.

Enhanced high-temperature iodine capture through band-edge control in covalent organic frameworks

The effective capture of radioactive iodine species is crucial in nuclear waste treatment, particularly under high-temperature industrial conditions (≥150 °C), yet it poses a significant challenge. Here, we propose a novel approach for constructing highly efficient iodine traps by precisely controlling band edges in covalent organic frameworks (COFs) through the incorporation of fluorine atoms. This strategy facilitates the transformation of I2 into I5−, thereby enhancing the interactions between the COF host and radioiodine species, leading to a remarkable iodine uptake capacity of up to 2.36 g/g under static adsorption condition at 150 °C, and 36.12 wt% under dynamic adsorption condition at 150 °C. Moreover, the captured iodine can be released by immersing the solid form in DMF solvent, providing a mean to modulate reaction conditions gently. Notably, TFA-COF material can be reused multiple times without significant loss in its iodine capture performance.

Synthesis and Characterization of Silver-Modified Nanoporous Silica Materials for Enhanced Iodine Removal.

In aquatic environments, the presence of iodine species, including radioactive isotopes like 129I and I2, poses significant environmental and health concerns. Iodine can enter water resources from various sources, including nuclear accidents, medical procedures, and natural occurrences. To address this issue, the use of natural occurring nanoporous minerals, such as zeolitic materials, for iodine removal will be explored. This study focuses on the adsorption of iodine by silver-modified zeolites (13X-Ag, 5A-Ag, Chabazite-Ag, and Clinoptilolite-Ag) and evaluates their performance under different conditions. All materials were characterized using scanning electron microscopey (SEM), energy-dispersive X-ray spectroscopy (EDS), powdered X-ray diffraction (P-XRD), Fourier-transform infrared spectrometry (FTIR), and nitrogen adsorption studies. The results indicate that Chabazite-Ag exhibited the highest iodine adsorption capacity, with an impressive 769 mg/g, making it a viable option for iodine removal applications. 13X-Ag and 5A-Ag also demonstrated substantial adsorption capacities of 714 mg/g and 556 mg/g, respectively, though their behavior varied according to different models. In contrast, Clinoptilolite-Ag exhibited strong pH-dependent behavior, rendering it less suitable for neutral to slightly acidic conditions. Furthermore, this study explored the impact of ionic strength on iodine adsorption, revealing that Chabazite-Ag is efficient in low-salinity environments with an iodine adsorption capacity of 51.80 mg/g but less effective in saline conditions. 5A-Ag proved to be a versatile option for various water treatments, maintaining its iodine adsorption capacity across different salinity levels. In contrast, Clinoptilolite-Ag exhibited high sensitivity to ionic competition, virtually losing its iodine adsorption ability at a NaCl concentration of 0.1 M. Kinetic studies indicated that the pseudo-second-order model best describes the adsorption process, suggesting chemisorption mechanisms dominate iodine removal. Chabazite-Ag exhibited the highest initial adsorption rate with a k2 value of 0.002 mg g-1 h-1, emphasizing its superior adsorption capabilities. Chabazite and Clinoptilolite, naturally occurring minerals, provide eco-friendly solutions for iodine adsorption. Chabazite superior iodine removal highlights its value in critical applications and its potential for addressing pressing environmental challenges.

Sodium iodide dopant mediated enhancements in energy storage characteristics of polysaccharide polymer electrolytes

Sodium iodide dopant influencing the properties of polysaccharide polymer sodium carboxymethyl cellulose is analyzed in this work by FTIR, XRD, DSC, TGA, SEM, UTM, and electrical. Solvation of I− and Na+ ions by the −OH group has disrupted the intra– and intermolecular hydrogen bonds between the polymers escorting to a decrease in crystallinity and creating a pathway for ion diffusion. The formation of transient crosslink and the physical environment created by the polymer-ion interaction have affected the rigidity of the polymer chains as well as the thermal stability of the NaCMC−NaI system. I− ion influences the ESW of the NaCMC−NaI system by forming various iodine species. Trapping of the I− ion for the NaCMC70−NaI30 sample has resulted in a drop in ionic conductivity manifested in the transient ionic current curve. A cation transference number of 0.14 indicates the dominance of anion in the ion conduction mechanism. An energy density of 720 mWhkg−1 and power density of 60 mWkg−1 was achieved for a dry cell incorporated with a CI25 sample as the electrolyte and separator.

Confinement of iodine species into oxygen doped hierarchical porous carbon host for high loading zinc-iodine batteries

The aqueous zinc-iodine batteries (ZIBs) have been expected to be the most promising next-generation energy storage device. However, it is still struggling with the limited intrinsic electronic conductivity, poor thermal stability and high solubility of the discharge products. Additionally, the iodine loading is below 2 mg cm−2 in most of the reported aqueous ZIBs, impeding their widespread application. Herein, we present a one-step production method for O-doped hierarchical porous carbon framework (OHPCF) from biomass as an iodine host material to solve the problems mentioned above. Benefiting from synergistic physical confinement (high-density microporous structure) and chemical anchoring (abundant oxygen atom doping) effect of the OHPCF samples, the electrode exhibits low polarization, high iodine utilization and excellent electrochemical stability in ZIBs. Encouragingly, we achieve an ultra-high area capacity of 3.3 mAh cm−2 with a loading of 20.3 mg cm−2, demonstrating its superior application potential. This work introduces a simple yet effective strategy for developing 3D microporous electrodes for ZIBs with high iodine loading, enabling high areal capacity with remarkable rate and cycling performance.

2D Conjugated Metal-Organic Frameworks Bearing Large Pore Apertures and Multiple Active Sites for High-Performance Aqueous Dual-Ion Batteries.

2D conjugated metal-organic frameworks (2D c-MOFs) with large pore sizes and high surface areas are advantageous for adsorbing iodine species to enhance the electrochemical performance of aqueous dual-ion batteries (ADIBs). However, most of the reported 2D c-MOFs feature microporous structures, with few examples exhibiting mesoporous characteristics. Herein, we developed two mesoporous 2D c-MOFs, namely PA-TAPA-Cu-MOF and PA-PyTTA-Cu-MOF, using newly designed arylimide based multitopic catechol ligands (6OH-PA-TAPA and 8OH-PA-PyTTA). Notably, PA-TAPA-Cu-MOF exhibits the largest pore sizes (3.9 nm) among all reported 2D c-MOFs. Furthermore, we demonstrated that these 2D c-MOFs can serve as promising cathode host materials for polyiodides in ADIBs for the first time. The incorporation of triphenylamine moieties in PA-TAPA-Cu-MOF resulted in a higher specific capacity (423.4 mAh g-1 after 100 cycles at 1.0 A g-1) and superior cycling performance, retaining 96 % capacity over 1000 cycles at 10 A g-1 compared to PA-PyTTA-Cu-MOF. Our comparative analysis revealed that the increased number of N anchoring sites and larger pore size in PA-TAPA-Cu-MOF facilitate efficient anchoring and conversion of I3 -, as supported by spectroscopic electrochemistry and density functional theory calculations.

Exploring contrast-enhancing staining agents for studying adipose tissue through contrast-enhanced computed tomography

Contrast-enhanced computed tomography offers a nondestructive approach to studying adipose tissue in 3D. Several contrast-enhancing staining agents (CESAs) have been explored, whereof osmium tetroxide (OsO4) is the most popular nowadays. However, due to the toxicity and volatility of the conventional OsO4, alternative CESAs with similar staining properties were desired. Hf-WD 1:2 POM and Hexabrix have proven effective for structural analysis of adipocytes using contrast-enhanced computed tomography but fail to provide chemical information. This study introduces isotonic Lugol’s iodine (IL) as an alternative CESA for adipose tissue analysis, comparing its staining potential with Hf-WD 1:2 POM and Hexabrix in murine caudal vertebrae and bovine muscle tissue strips. Single and sequential staining protocols were compared to assess the maximization of information extraction from each sample. The study investigated interactions, distribution, and reactivity of iodine species towards biomolecules using simplified model systems and assesses the potential of the CESA to provide chemical information. (Bio)chemical analyses on whole tissues revealed that differences in adipocyte gray values post-IL staining were associated with chemical distinctions between bovine muscle tissue and murine caudal vertebrae. More specific, a difference in the degree of unsaturation of fatty acids was identified as a likely contributor, though not the sole determinant of gray value differences. This research sheds light on the potential of IL as a CESA, offering both structural and chemical insights into adipose tissue composition.

A Highly Sterically Encumbered Boron Lewis Acid Enabled by an Organotellurium-Based Ligand.

Lewis acidic boron compounds are ubiquitous in chemistry due to their numerous applications, yet tuning and optimizing their properties towards different purposes is still a challenging field of research. In this work, the boron-based Lewis acid B[OTeF3(C6F5)2]3 was synthesized by reaction of the teflate derivative HOTeF3(C6F5)2 with BCl3 or BCl3 ⋅ SMe2. This new compound presents a remarkably high thermal stability up to 300 °C, as well as one of the most sterically encumbered boron centres known in the literature. Theoretical and experimental methods revealed that B[OTeF3(C6F5)2]3 exhibits a comparable Lewis acidity to that of the well-known B(C6F5)3. The affinity of B[OTeF3(C6F5)2]3 towards pyridine was accessed by Isothermal Titration Calorimetry (ITC) and compared to that of B(OTeF5)3 and B(C6F5)3. The ligand-transfer reactivity of this new boron compound towards different fluorides was demonstrated by the formation of an anionic Au(III) complex and a hypervalent iodine(III) species.

Comparison of dissolved iodine measurements in seawater between inductively coupled plasma mass spectrometry and voltammetry.

Two analytical methods, inductively coupled plasma mass spectrometry (ICP-MS) combined with high-performance liquid chromatography (HPLC) and voltammetry (VM), for three chemical species of dissolved iodine (iodide, iodate, and total dissolved iodine: TDI) were compared for dozens of coastal seawater samples owing to the compatibility of data between both methods. The median differences in the measured concentrations of TDI, total inorganic dissolved iodine (TII, the sum of iodide and iodate), and iodate between ICP-MS and VM were equivalent to 9.2, 13, and 14%, respectively. These differences were within the ranges that could be explained by the repeated-measurement precision of each measurement method for TDI, TII, and iodate. The difference for iodide was 19%, which was larger than the value based on the repeated-measurement precision for both methods. This is considered to be caused by the chemical instability and lower concentrations of iodide compared to other iodine species in seawater, in addition to the heterogeneity of natural samples. Finally, both methods provided reasonable measurement values for the iodine concentration in natural seawater samples.

Unveiling the Role of Cationic Pyridine Sites in Covalent Triazine Framework for Boosting Zinc-Iodine Batteries Performance.

Rechargeable Zinc-iodine batteries (ZIBs) are gaining attention as energy storage devices due to their high energy density, low-cost, and inherent safety. However, the poor cycling performance of these batteries always arises from the severe leakage and shuttle effect of polyiodides (I3 - and I5 -). Herein, a novel cationic pyridine-rich covalent triazine framework (CCTF-TPMB) is developed to capture and confine iodine (I2) species via strong electrostatic interaction, making it an attractive host for I2 in ZIBs. The as-fabricated ZIBs with I2 loaded CCTF-TPMB (I2@CCTF-TPMB) cathode achieve a large specific capacity of 243mAhg-1 at 0.2Ag-1 and an exceptionally stable cyclic performance, retaining 93.9% of its capacity over 30000 cycles at 5Ag-1. The excellent electrochemical performance of the ZIBs can be attributed to the pyridine-rich cationic sites of CCTF-TPMB, which effectively suppress the leakage and shuttle of polyiodides, while also accelerating the conversion reaction of I2 species. Combined in situ Raman and UV-vis analysis, along with theoretical calculations, clearly reveal the critical role played by pyridine-rich cationic sites in boosting the ZIBs performances. This work opens up a promising pathway for designing advanced I2 cathode materials toward next-generation ZIBs and beyond.

Iodine-doped carbon nanotubes boosting the adsorption effect and conversion kinetics of lithium-sulfur batteries

Compared with lithium-ion batteries (LIBs), lithium-sulfur batteries (LSBs), based on electrochemical reactions involving multi-step 16-electron transformations provide higher specific capacity (1672 mAh g−1) and specific energy (2600 Wh kg−1), exhibiting great potential in the field of energy storage. However, the inherent insulation of sulfur, slow electrochemical reaction kinetics and detrimental shuttle-effect of lithium polysulfides (LiPSs) restrict the development of LSBs in practical applications. Herein, the iodine-doped carbon nanotubes (I-CNTs) is firstly reported as sulfur host material to the enhance the adsorption-conversion kinetics of LSBs. Iodine doping can significantly improve the polarity of I-CNTs. Iodine atoms with lone pair electrons (Lewis base) in iodine-doped CNTs can interact with lithium cations (Lewis acidic) in LiPSs, thereby anchoring polysulfides and suppressing subsequent shuttling behavior. Moreover, the charge transfer between iodine species (electron acceptor) and CNTs (electron donor) decreases the gap band and subsequently improves the conductivity of I-CNTs. The enhanced adsorption effect and conductivity are beneficial for accelerating reaction kinetics and enhancing electrocatalytic activity. The in-situ Raman spectroscopy, quasi in-situ electrochemical impedance spectroscopy (EIS) and Li2S potentiostatic deposition current–time (i-t) curves were conducted to verify mechanism of complex sulfur reduction reaction (SRR). Owing to above advantages, the I-CNTs@S composite cathode exhibits an ultrahigh initial capacity of 1326 mAh g−1 as well as outstanding cyclicability and rate performance. Our research results provide inspirations for the design of multifunctional host material for sulfur/carbon composite cathodes in LSBs.

Stability testing of iomeprol and iopamidol formulations subjected to X-ray radiation

IntroductionExposure of iodinated contrast media (ICM) to X-rays is not uncommon, as contrast media are often stored in close proximity to radiological equipment. However, the interaction between X-rays and ICM is not widely investigated in literature. The present study aims to investigate the chemical stability of iomeprol and iopamidol, two commercial iodinated ICM commonly used in diagnostic imaging, under X-rays exposure. MethodsDifferent formulations of iopamidol and iomeprol (iodine concentration 9 to 400 mgI/mL, volume 50–500 mL) were exposed to three different conditions of X-ray irradiation: i) 1 month storage in CT room (≈5–15 mGy); (ii) low-dose protocol (≈10 mGy); (ii) stressed protocol (≈100 mGy). Unexposed and exposed solutions were characterized by high-performance liquid chromatography in terms of concentration of active pharmaceutical ingredient (API), iodine species and by products. In addition, appearance and colour of the solutions were inspected and pH measured. ResultsAPI concentrations, appearance, colour and pH of the exposed formulations remained unaffected by X-rays. Measured concentrations of iodine species and by products were observed well within the acceptability criteria, i.e. values turned out to be lower than specifications limits established by the manufacturer, considering both release and shelf-life values. ConclusionsUp to 100 mGy X-ray exposure did not induce any alteration of iomeprol and iopamidol formulation, nor a detectable increase in the concentration of iodine species or by-products. Implications for practiceOur study strengthens the hypothesis that ICM are stable under X-rays exposure up to 100 mGy.

An electronegative biomimetic separator suppresses side effects of iodine species in Li-O2 batteries

LiI in Li-O2 batteries has shown promise in reducing charge overpotential. However, the shuttle effect of oxidated iodine species (OISs) can lead to lithium metal corrosion and loss of OISs. During the discharging process, these iodine species can undergo side reactions, resulting in the accumulation of LiOH and other parasitic products, which in turn accelerates battery failure. In this work, we have drawn inspiration from mussel protein and utilized a simple co-deposition method to form a robust biomimetic functionalized coating on the surface of the glass fiber separator. This was achieved by grafting catechol/polyamine (CA/PA) with 11-mercaptoundecanoic acid (MUA). This separator exhibits strong electrostatic repulsion towards negatively charged OISs and, conversely, electrostatic attraction towards Li+, this dual action effectively suppresses the shuttle effect and facilitates Li+ transport. When equipped with this modified separator, the Li-O2 battery effectively reduces the accumulation of LiOH and demonstrates significantly enhanced rate performance and cycle stability. Our findings provide a versatile approach for the design of modified separators for Li-O2 batteries with redox mediators (RMs).

Porous Aromatic Frameworks Enabling Polyiodide Confinement toward High Capacity and Long Lifespan Zinc-Iodine Batteries.

Aqueous zinc-iodine batteries (AZIBs) are attracting increasing attention because of their high safety and abundance of resources. However, the performance of AZIBs is compromised by inadequate confinement of soluble polyiodides, the undesired shuttle effect, and slow reaction kinetics. In this study, a porous aromatic framework (PAF) with abundant benzene motifs and a well-organized pore structure is adopted as the iodine host, which exhibits high iodine adsorption capacity and robust polyiodide confinement. Both experimental characterizations and theoretical simulations indicate that the interactions between iodine species and the PAF-1 facilitate the redox reaction by coupling the electronic structures of the active species in the framework. A comparison of PAF-1, PAF-5, and PAF-11 also emphasizes the structural advantages of the high surface area and interconnected three-dimensional channels of PAF-1. Consequently, the I2@PAF-1 cathode can deliver a high capacity of 328 mAh g-1 at 0.5 C, outstanding rate performance, and a stable cycling life of 20000 cycles (86 % retention at 10 C). The robust polyiodide confinement and superb electrochemical performance of Zn-I2@PAF-1 provide insights into the practical application of PAFs as excellent electrode materials for AZIBs.