H2O2 Solution Research Articles

Ion pair self-assembly composed of polyamidoamine dendrimer and phenylthio acetic acid and its temperature and oxidation-responsive release property

Polyamidoamine (PAMAM) dendrimer/phenylthio acetic acid (PTA) ion pair could be generated when the amino/carboxyl group ratio was 3/7 to 1/9. The chemical shifts on 1H NMR and FT-IR spectra suggested that PTA interacted ionically with PAMAM. The PTA was oxidized to sulfoxide and sulfone by H2O2, evidenced by 1H NMR and FT-IR spectroscopy. The ion pair exhibited upper critical solution temperature (UCST) and air/water interface-active which could decrease upon PTA oxidation. When the medium temperature was higher than the UCST, the substantial release of dye loaded in IPSAM took place in the H2O2 solution.

Study on the curing conditions on the physico-mechanical and environmental performance of phosphogypsum-based artificial aggregates

The considerable accumulation of phosphogypsum (PG) not only occupies land space but also causes environmental pollution, leading to threatening human health. Under the background of the current massive demand for construction concrete, the problem of natural aggregate shortage urgently needs to be solved. In this research, the raw materials of PG, slag, and cement were adopted to prepare PG-based artificial aggregates (PBAAs) by compression methods, which aimed to develop the applications of PG to construction concrete materials. The different curing temperatures and solutions (Na2SO4 and CaSO4·2 H2O) were investigated to explore the effects of curing conditions on the physical properties and ion leaching of PBAAs. The performance of PBAAs from the aspects of compressive strength, pH value, bulk density, softening coefficient, water absorption, and carbonization degree was evaluated. The microscopic morphology analysis and phase, as well as quantitative analysis were conducted by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively, to study the hydration mechanism of PBAAs under different curing conditions. The Avrami model was used to simulate the PG dissolution rate of PBAAs. The results showed that 40 °C was the most favorable temperature for PBAAs and that the dissolution of PG during immersion curing was mainly controlled by ion reactions. The PBAAs cured in saturated Na2SO4 solution raised the pH value of the curing solution. The curing conditions of CaSO4·2 H2O at 40 °C inhibited the dissolution of PG in raw materials, and provided Ca2+ for the formation of ettringite and C-S-H gel, thereby increasing the bulk density, compressive strength, carbonization resistance, and reducing the water absorption rate of PBAAs. Moreover, PBAAs cured in saturated CaSO4·2 H2O and Na2SO4 solutions at 40 °C effectively solidified heavy metals and P elements in PG. This study contributes to developing the replacement of natural aggregates by PBAAs in construction concrete, which can reduce the consumption of natural aggregates and improve the utilization rate of PG.

Empowering silver and copper nanoparticles through aqueous fruit extract of Solanum xanthocarpum for sustainable advancements

AbstractSilver and copper nanoparticles were biosynthesized from AgNO3 & CuSO4.5H2O solution by using fruits extract of Solanum xanthocarpum. These nanoparticles (NPs) were characterized by UV, FTIR, and SEM techniques and evaluated for biological activities. The UV absorption peaks of biosynthesized Ag and CuNPs were observed at 452 nm and 549 nm, respectively. The FTIR analyses of the fruits extracts were carried out to identify the possible classes of chemical compounds responsible for NPs stability and reduction. The crystalline structure and size of NPs were characterized by using SEM. The NPs were tested against some selected pathogenic strains. In the current study, the tested bacterial and fungal strains were found sensitive to biosynthesized Ag and CuNPs at concentrations (25μg/mL, 50μg/mL, 75μg/mL, and 100μg/mL). The overall results show that, the antimicrobial activities of CuNPs were comparatively more potent than AgNPs. Antioxidant activities of Ag and CuNPs were evaluated using the DPPH method. The results showed effective free radical scavenging activities, but AgNPs exhibited more significant activities as compared to CuNPs. Anticancer activities were measured by using the MTT assay, Cell viability was used to determine the cytotoxic activity of NPs using HepG2 hepatocellular carcinoma cell line. In the present study, the NPs prevented the growth of tumor cells in a dose-dependent manner (5–500μg/mL). With a gradual increase in NPs concentration, the cell viability of cancer cells decreased. The two highest NPs concentrations (100μg/mL & 250μg/mL) significantly decreased cell viability. The results exhibited that AgNPs are more effective than CuNPs. Additionally, they exhibited effective biological activities, making them to be used in medical sector for cancer treatment, sensors, medications delivery, and several other applications.

A flavonol-labelled cellulose fluorescent probe combined with composite fluorescent film imaging and smartphone technology for the detection of Fe3+

Fe3+ is one of the most widely distributed and abundant elements on earth. Realizing efficient and real-time monitoring of Fe3+ is of great significance for the natural environment and the health of living organisms. In this paper, a flavonol-labelled cellulose-based fluorescent probe (ACHM) was synthesized by using dialdehyde cellulose (DAC) as the backbone and combining with flavonol derivatives (AHM - 1). The mechanism of recognizing Fe3+ was verified by characterizing the structure of ACHM by NMR, HRMS (High Resolution Mass Spectrometry), FTIR (Fourier Transform Infrared Spectroscopy), XRD (X-ray Diffraction), TG (Thermogravimetry) and SEM (Scanning Electron Microscopy). The H2O solution of the probe ACHM showed good fluorescence properties. It has quenching fluorescence properties for Fe3+, with a low limit of detection (LOD) of 0.10 μM and a fast response time of only 20 s. In addition, in order to expand the application range of the probe, ACHM was prepared as a fluorescent composite film with an average tensile strength of 32.9 MPa and an average elongation at break of 3.39 %. It shows its superiority in mechanical properties. The probe also demonstrated its practical application value for detecting Fe3+ in smartphone imaging applications.

Efficient Photosynthesis of Hydrogen Peroxide by Cyano-Containing Covalent Organic Frameworks from Water, Air and Sunlight.

The insufficient exciton (e- -h+ pair) separation/transfer and sluggish two-electron water oxidation are two main factors limiting the H2 O2 photosynthetic efficiency of covalent organic frameworks (COFs) photocatalysts. Herein, we present an alternative strategy to simultaneously facilitate exciton separation/transfer and reduce the energy barrier of two-electron water oxidation in COFs via a dicyano functionalization. The in situ characterization and theoretical calculations reveal that the dicyano functionalization improves the amount of charge transfer channels between donor and acceptor units from two in COF-0CN without cyano functionalization to three in COF-1CN with mono-cyano functionalization and four in COF-2CN with dicyano functionalization, leading to the highest separation/transfer efficiency in COF-2CN. More importantly, the dicyano group activates the neighbouring C atom to produce the key *OH intermediate for effectively reducing the energy barrier of rate-determining two-electron water oxidation in H2 O2 photosynthesis. The simultaneously enhanced exciton separation/transfer and two-electron water oxidation in COF-2CN result in high H2 O2 yield (1601 μmol g-1 h-1 ) from water and oxygen without using sacrificial reagent under visible-light irradiation. COF-2CN can effectively yield H2 O2 in water with wide pH range, in different real water samples, in scaled-up reactor under natural sunlight irradiation, and in continuous-flow reactor for consecutively producing H2 O2 solution for water decontamination.

Efficient Photosynthesis of Hydrogen Peroxide by Cyano‐Containing Covalent Organic Frameworks from Water, Air and Sunlight

AbstractThe insufficient exciton (e−‐h+ pair) separation/transfer and sluggish two‐electron water oxidation are two main factors limiting the H2O2 photosynthetic efficiency of covalent organic frameworks (COFs) photocatalysts. Herein, we present an alternative strategy to simultaneously facilitate exciton separation/transfer and reduce the energy barrier of two‐electron water oxidation in COFs via a dicyano functionalization. The in situ characterization and theoretical calculations reveal that the dicyano functionalization improves the amount of charge transfer channels between donor and acceptor units from two in COF‐0CN without cyano functionalization to three in COF‐1CN with mono‐cyano functionalization and four in COF‐2CN with dicyano functionalization, leading to the highest separation/transfer efficiency in COF‐2CN. More importantly, the dicyano group activates the neighbouring C atom to produce the key *OH intermediate for effectively reducing the energy barrier of rate‐determining two‐electron water oxidation in H2O2 photosynthesis. The simultaneously enhanced exciton separation/transfer and two‐electron water oxidation in COF‐2CN result in high H2O2 yield (1601 μmol g−1 h−1) from water and oxygen without using sacrificial reagent under visible‐light irradiation. COF‐2CN can effectively yield H2O2 in water with wide pH range, in different real water samples, in scaled‐up reactor under natural sunlight irradiation, and in continuous‐flow reactor for consecutively producing H2O2 solution for water decontamination.

Fe-containing sphalerite as a co-catalyst for degradation of Congo red dye

Complex sulfide ores are associated with various sulfide minerals, characterized by their impurity content and physical defects. Sphalerite, a well known Zn-bearing mineral, consists of sulfides and inevitably contains various impurities. In this regard, minor metals in Zn concentrate complicate the flotation process or hydrometallurgical process. Nevertheless, the Fe-containing sphalerite is regarded as an efficient inorganic co-catalyst due to its surface properties with unsaturated S atoms and Fe atoms. Typically, the Fe(III) reduction determines the overall efficiency of the Fenton process, necessitating a stoichiometric excess of H2O2 and catalysts. To address the limitations of the Fenton process, this study proposes the use of Fe-containing sphalerite (ZnS) as co-catalysts to enhance the Fe(III)-H2O2 system. The redox reactions between ZnS and Fe(III) can efficiently decompose H2O2, which promotes the reaction between Fe(III) and Fe(II). Therefore, in this study, ZnS was evaluated as a co-catalyst to enhance the Fenton-like system for the degradation of Congo red (CR). The CR degradation was examined using different processes involving a single factor (ZnS, H2O2), dual factor (ZnS-H2O2, Fe(II)-H2O2, Fe(III)-H2O2), and triple factor (ZnS-Fe(III)-H2O2), to demonstrate co-catalyst effect. It was confirmed that both ZnS and Fe(III) were introduced into the system. Remarkably, 98.9% of ZnS-Fe(III)-H2O2 was degraded within 5 min, underscoring the effectiveness of ZnS as a co-catalyst in enhancing the activating of H2O2. When ZnS-Fe(III)-H2O2 system was used, CR degradation was affected by Fe(III) and H2O2 concentration, ZnS doses, and solution pH. During the reuse experiments, CR could be completely degraded, and Co-catalytic efficiency of ZnS was maintained for three reuse cycles.

A feasible method for the composition analysis and chemical remediation of clogging matter in subsurface flow constructed wetlands

The problem of clogging, especially biological clogging, makes the long-term operation of subsurface flow constructed wetlands challenging. This study focused on the two subsurface flow constructed wetlands receiving reclaimed water near the Tuhai River of Shandong Province, aiming to provide a feasible method for the composition analysis and chemical remediation by H2O2 solution of clogging matter. The compositions and distributions of clogging matter in these two wetlands were analyzed, and the effects of H2O2 solutions with different mass fractions on proteins, polysaccharides, nucleic acids, and humic acids in the organic clogging components were studied. The two case studies indicated that the contents of clogging matter in the two subsurface flow constructed wetlands varied greatly due to the operation time and operation mode, and the proportion of inorganic components was higher than that of organic components. The organic components of the clogging matter were mainly proteins and humic acids, with very small amounts of polysaccharides and nucleic acids. In addition, the H2O2 solution with a mass fraction of 10% had a good removal effect on proteins and humic acids in the wetland substrates, which also could increase the permeability coefficient of the substrates without causing a large negative impact on the temperature and pH value of the wetland systems. This article proposed a simple, economical, environmentally friendly method for analyzing and remediating biological clogging of subsurface flow constructed wetlands, which was expected to be widely used in situ remediation of clogging matter.

Biodegradable MoNx@Mo-foil electrodes for human-friendly supercapacitors.

With the advancement in the field of biomedical research, there is a growing demand for biodegradable electronic devices. Biodegradable supercapacitors (SCs) have emerged as an ideal solution for mitigating the risks associated with secondary surgeries, reducing patient discomfort, and promoting environmental sustainability. In this study, MoNx@Mo-foil was prepared as an active material for biodegradable supercapacitors through high-temperature and nitridation processes. The composite electrode exhibited superior electrochemical performance in both aqueous and solid-state electrolytes. In the case of the solid-state electrolyte, the MoNx@Mo-foil composite electrode-based device demonstrated excellent cycling stability and electrochemical performance. Additionally, the composite electrode exhibited rapid and complete biodegradability in a 3% H2O2 solution. Through detailed experimental analysis and performance testing, we verified the potential application of the MoNx@Mo-foil composite electrode in biodegradable supercapacitors. This work provides a new choice of degradable material for developing biomedical electronic devices.

Rapid synthesis of Pt(0) motors-microscrolls on a nickel surface via H2PtCl6-induced galvanic replacement reaction.

In this study, Pt(0) microscrolls are synthesized on polished Ni via galvanic replacement reaction (GRR). Employing in situ optical microscopy, the dynamic motion of the catalytic microscrolls as micromotors in H2O2 solutions is revealed. This method offers a rapid fabrication of scrolls from diverse noble metals and alloys.

Development of eco-friendly pretreatment processes for high-purity silicon recovery from end-of-life photovoltaic modules.

This study examines the efficacy of photovoltaic (PV) recycling processes and technologies for the recovery of high-purity silicon powder from waste solar modules. In order to facilitate the simplification of complex processes, such as the conventional nitric acid dissolution, solvent and ultrasonic irradiation, and solvent dissolution, a variety of mechanical separation processes have been established. These processes are designed to enhance the efficiency and effectiveness of the aforementioned processes. And a novel method for separating EVA from recycled Si powder was devised, which studied the WGS process using aqueous solutions of H2O, HNO3, and NaCl with different specific gravities. The WGS process using NaCl solution demonstrated superior performance, removing over 94% of the EVA, requiring less energy input and producing 73% less CO2 emissions compared to the thermal process. These technologies facilitate the transition towards a circular economy and bolster the implementation of carbon-neutral initiatives.

Experimental investigation of carbon dioxide hydrate formation in a colloidal solution of H2O+ SDS + SiO2 at a constant SiO2 concentration of 300 ppm

The paper presents a experimental investigation of carbon dioxide hydrate formation in a colloidal solution of H2O+ SDS + SiO2 The influence of the kinetic promoter of sodium dodecyl sulfate (SDS) on the formation of carbon dioxide gas hydrate at various concentrations: 0, 100, 300, 500 ppm was assessed. The SiO2 concentration in the solution was constant and equal to 300 ppm. The change in solution temperature and pressure during the production of hydrate is shown for each SDS concentration. The values of convection of solution and gas into the gas hydrate state were determined.

A self-assembled three-dimensional hierarchical nanoflower: an efficient enzyme-mimetic material for cancer cell detection that improves ROS generation for therapy.

Three-dimensional (3D) nanomaterials with high functional properties are emerging as the most promising artificial enzymes for overcoming the significant disadvantages of natural enzymes. Anticancer therapy using 3D-enzyme mimetic materials has emerged as an essential development for catalyzing cancer cell destruction. We report for the first time a novel 3D-based enzyme mimetic material, CaMoO4/MoS2/CuS nanoflower (CMC NF), that exhibits a large specific surface area, uniform flower-like structure, excellent biocompatibility, and high porosity, making it a suitable candidate for cancer detection and therapy. Additionally, CMC NFs were conjugated with folic acid (FA) to selectively target cancer cells, resulting in FA-CMC NFs explicitly binding to overexpressed folate receptor alpha (FRα) in MDA-MB-231 cells. Based on the peroxidase activity, the FA-CMC NFs are an effective nanoprobe for the selective detection of MDA-MB-231 cells over a wide detection range (50 to 5.5 × 104 cells per mL) with a low limit of detection (LOD) value of 10 cells per mL. In addition to their cancer detection capability, the FA-CMC NFs also effectively generated ˙OH radicals in a concentration-dependent manner to treat cancer cells. Under light conditions, the FA-CMC NFs with H2O2 solution showed efficient degradation of methylene blue (MB) dye, and the solution color appeared to fade within 15 min, indicating that they generated ˙OH radicals, which can efficiently kill cancer cells. Thus, the superior functionality of FA-CMC NFs offers cost-effective, facile, and reliable cancer cell detection, providing a new treatment option for cancer treatment and diagnosis.

A novel magnetically guided, oxygen propelled CoPt/Au nanosheet motor in conjugation with a multilayer hollow microcapsule for effective drug delivery and light triggered drug release.

In recent years, nanomotors have been developed and attracted extensive attention in biomedical applications. In this work, a magnetically-guided oxygen-propelled CoPt/gold nanosheet motor (NSM) was prepared and used as an active self-propelled platform that can load, transfer and control the release of drug carrier to cancer cells. As a drug carrier, the microcapsules were constructed by the layer-by-layer (LbL) coating of chitosan and carboxymethyl cellulose layers, followed by incorporation of gold and magnetite nanoparticles. Doxorubicin (DOX) as an anti-cancer drug was loaded onto the synthesized microcapsules with a loading efficiency of 77%. The prepared NSMs can deliver the DOX loaded magnetic multilayer microcapsule to the target cancer cell based on the catalytic decomposition of H2O2 solution (1% v/v) via guidance from an external magnetic force. The velocity of NSM was determined to be 25.1 μm s-1 in 1% H2O2. Under near-infrared irradiation, and due to the photothermal effect of the gold nanoparticles, the proposed system was found to rapidly release more drugs compared to that of an internal stimulus diffusion process. Moreover, the investigation of cytotoxicity of NSMs and multilayer microcapsules clearly revealed that they have negligible side effects over all the concentrations tested.

Modulation of soil aeration and antioxidant defenses with hydrogen peroxide improves the growth of winter wheat (Triticum aestivum L.) plants

Soils with subsurface drip irrigation are often characterized by hypoxia, which could impair the aerobic respiration of roots and the productive potential of crops. Irrigation with hydrogen peroxide oxygenated water (HPOW) is one way to improve soil aeration in the rhizosphere. However, few studies have focused on exploring the interaction of HPOW with soil aeration and productivity of crops. The current work aimed to investigate the effects of four levels of HPOW [0 ppm H2O2 solution (tap water) as a control (H0), 600 ppm, 800 ppm and 1000 ppm H2O2 solution (H600, H800 and H1000)] on irrigation water properties, soil aeration, antioxidant defenses, growth biomarkers and yield components in winter wheat (Triticum aestivum L.) plants. Results confirmed that dissolved oxygen (DO) concentrations in H600, H800 and H1000 were significantly increased by 52.10%–126.59% and surface tension coefficients were significantly decreased by 17.72%–31.60% as compared to H0. DO concentrations in soil solutions irrigated with H600, H800 and H1000 were significantly elevated by 9.78%–15.68% as compared to H0, and the maximum value equal to 7.44 mg L−1 was found at a soil depth of 20 cm. Further, H600 and H800 reduced concentrations of malondialdehyde and H2O2 in leaves, increased accumulation of proline and activities of antioxidant enzymes, and resulted in an enhancement in grain yield of 15.28% and 25.23%, respectively. Application of H1000 resulted in lower growth biomarkers and yield components due to oxidative stress induced by decreased activities of antioxidant enzymes and accumulation of proline as well as elevated levels of lipid peroxidation as compared to H600 and H800. The optimal regulation was achieved with the H800 treatment. Overall, HPOW improved the plants growth by modulating soil aeration and antioxidant defenses which enhanced tolerance to hypoxic stress.

Fabrication of magnetic activated carbon from corn-cob biomass for the removal of acidic dyes from wastewater

Herein, iron oxide nanocomposites were prepared using corn cob waste biomass and Fe (NO3)3.9 H2O as iron source. The dried corn cob in grinded form were mixed with Fe (NO3)3.9 H2O solution heated for 60 min at 300 °C in nitrogen atmosphere to ensure complete carbonization. The exterior morphology, particle sizes, crystallinity, and elemental content etc. of the fabricated composite were SEM, XRD, and EDX analysis respectively. The XRD confirmed the presence of iron oxide on activated carbon framework and also validated the nano sized dimensions of resulting magnetic adsorbent. The nanocomposites were then employed as adsorbent for the removal of acid orange 8 and acid red 4 dyes from aqueous medium. To get maximum adsorption of selected dyes the experimental conditions like dosage of the adsorbent, temperature, and contact time were optimized. Langmuir and pseudo second order kinetics models best fitted experimental isotherm and kinetics data respectively. The optimum removal of selected dyes was achieved with 0.01 g of adsorbent dosage whereas equilibrium for both the dyes were achieved in 1 h. Additionally, the Gibbs free energy (ΔG°), enthalpy (ΔH°), and entropy (ΔS°) of the adsorption were enumerated using Vant’s Hof plot. The adsorption processes were found to be endothermic, as evident from positive values of ΔH° = 9.651 kJ/mol for AO 8 and 16.493 kJ/mol for AR 4. The processes in both the cases were found as spontaneous at higher temperature, evident from the positive to negative trending values of ΔG° (714.29, 104.28, and −505.733 J/mol for AO 8 and 271.93, −835.306, and −1942.54 J/mol for AR 4 at 20 °C, 40 °C, and 60 °C respectively. The positive entropy change (ΔS°) values of 30.5007 J/mol.K and 55.362 J/mol.K recorded, indicates the increasing disorder at the solid-solution interface for both the dyes. An attempt was made to recycle adsorbent using suitable solvents and up to 5 cycles the removing efficiency retained was still 76%.

One-pot fabrication of potent antimicrobial and antiviral films with eco-friendly in situ after-use disposal

Antimicrobial and antiviral films are effective barriers that can impede the transmission of deleterious pathogens and safeguard human health. However, the broad utilization of these materials has been hampered by their costs and availability, difficulties in mass manufacture, and concerns about their accumulation as landfill wastes endangering the ecosystems. Here, we developed a facile process to fabricate potent antimicrobial and antiviral films following one-step in situ thermal curing at 140 °C for only 10 min. These films were derived from thermal modifications of polyvinyl alcohol (PVA) acidified with sulfuric acid and loaded with 0 – 1 % (w/w) of akaganéite (β-FeOOH) nanorods. The optimized films rapidly eliminated the majority (80 – 100 %) of Staphylococcus aureus, Escherichia coli, and Influenza A viruses after 10 min of surface contact. Moreover, owing to the β-FeOOH-mediated catalysis of hydrogen peroxide (H2O2), the composite films can be in situ modified after brief immersion in H2O2 aqueous solutions, and ultimately dissolved to yield ‘zero solid waste’. The bacteria-killing efficacies of these films and their dissolution in H2O2 solutions can be easily promoted by simulated sunlight irradiation. This work provides a simple scheme to fabricate powerful antimicrobial and antiviral films using low-cost, readily available, eco-friendly, and highly scalable materials. The current films are promising interface materials to confront widespread outbreaks of infectious bacteria and enveloped viruses without imposing severe environmental burdens.

A new methodology for foraminifera extraction from cemented calcareous shelf sediments

Choosing the most conservative technique to extract unequivocally identifiable foraminiferal tests is crucial to avoid biases in sedimentary sequence dating and paleoenvironmental interpretations. However, for problematic samples containing heavily encrusted specimens, the concentration and isolation of microfossils might be challenging. In this work, we analyzed Early-Middle Pleistocene samples from the International Ocean Discovery Program (IODP) Site U1460, located on the southwestern Australian shelf platform, characterized by extensive early marine diagenesis. At this site, foraminiferal preservation varies between the glacial and interglacial phases. In particular, tests are highly encrusted in samples representing sea-level lowstands of glacials while exhibiting better preservation in samples corresponding to interglacials. As the application of previously established, very conservative preparation techniques (e.g., sieving technique, soaking in H2O2 solution and gentle sonication) did not produce satisfactory results, it was necessary to set up a new procedure for foraminifera isolation specifically for the cautious cleaning of cemented benthic and planktic foraminiferal tests. This new methodology combines the use of a freeze-dryer with repeated soakings in highly-diluted H2O2 solution to disaggregate the material. To evaluate the efficiency of our technique objectively, we considered the improvements obtained with our procedure on the worst-preserved samples of our record (corresponding to glacials) and the best-preserved (associated with interglacials). Despite being more time-consuming than other preparation techniques, this newly developed procedure produces excellent results in samples exhibiting a high level of encrustation for reliable quantitative studies and isotope analysis on foraminiferal assemblages. Our new methodology is highly conservative and thus preserving even delicate taxa.

Rhein/carbon nanotube derived carbon materials with quinone group for hydrogen peroxide electrosynthesis

Oxygen-doped carbon materials (OC) have been studied as the electrocatalysts of two-electron oxygen reduction reaction (2-e ORR) to synthesize H2O2 due to their low cost and high selectivity. In this study, quinone group contained OC (OC-R/CNT) were prepared using the mixture of rhein with quinone group and carbon nanotube (CNT) as the precursor via one-step pyrolysis. The RRDE test showed that the OC-R/CNT gave a H2O2 selectivity of 94 % at 0.20 V in neutral medium. During the H-cell test, the H2O2 yield of OC-R/CNT can be up to 170 mmol gcat−1 h−1 at 0 V vs. RHE and the OC-R/CNT catalyst exhibited good long-term stability and reusability. The H2O2 solution produced at 0 V vs. RHE for 1 hour showed good bactericidal properties. For comparison, the OC without quinone group (OC-G/CNT) were also prepared with glucose and CNT as the precursor under the same condition, which showed poorer 2-e ORR catalytic performance. This study not only provides a feasible method to prepare quinone group contained carbon materials but also verifies the important role of quinone group in 2-e ORR.

Long Cycle Life Rechargeable Moisture‐Enabled Electricity Cell

AbstractMoisture‐enabled electricity generation (MEG) is a prominent renewable energy harvesting technology in hydrovoltaic power generation, boasting the broadest energy harvesting spectrum. However, practical application faces limitations due to irreversible performance degradation caused by structural changes and moisture‐generated carrier (MGC) losses in Moisture‐enabled electricity (ME) materials, rendering them non‐renewable. This study introduces a rechargeable moisture‐enabled electricity cell (rMEC) based on dual ME functional layers and active metal electrodes. The rMEC demonstrates outstanding power generation performance, with a single cell providing an output voltage of 1.08 V and a power density of 5.83 µW cm−2 through redox assistance. Moreover, it can be recharged when MGCs are lost, utilizing the reversibility of the redox reaction (moisture of H2O2 solution) for self‐repair. Notebly, the rMEC maintains stable operation for over 2080 h and undergoes 100 charging/working cycles, marking the longest span life record in MEG research history. When exposed to industrial wastewater/gases with oxidation characteristics, the rMEC not only completes charging but also facilitates the reuse of toxic waste resources. The environmentally friendly rMEC, with its long cycle life, significantly overcomes the limitations of non‐renewable ME materials, serving as a paradigm for promoting iterative upgrades in MEG technology.