Synthesis Of Peroxide Research Articles

Recent advances in tailoring the microenvironment of Pd-based catalysts for enhancing the performance in the direct synthesis of hydrogen peroxide.

Hydrogen peroxide (H2O2) is a valuable clean chemical, which is widely applied in modern industrial production. In the past few decades, H2O2 has been mainly produced industrially by the anthraquinone method, but the process is complicated and energy consuming, which is only economical for large-scale production and is harmful to the environment. The direct synthesis of H2O2 is considered a promising process to replace the anthraquinone method with high atomic economy, no hazardous by-products, and convenient operation, which has attracted much attention. In this review, we systematically present the recent advances in tuning the microenvironment of Pd-based catalysts for enhancing the performance of the direct synthesis of H2O2, including the modulation of active sites and support, from the viewpoint of the reaction mechanism. Finally, a summary and perspective on the most pressing issues and associated untapped research prospects with the direct synthesis of H2O2 are discussed. The purpose of this review is to provide in-depth insights and guidelines to promote the development of novel catalysts for the direct synthesis of H2O2.

Cooperative tungsten centers in polymeric carbon nitride for efficient overall photosynthesis of hydrogen peroxide

Meticulously designed neighboring WOR and ORR active sites significantly enhance the overall photocatalytic synthesis of hydrogen peroxide.

Electrocatalytic synthesis of hydrogen peroxide based on multi-doped carbon-based nanocatalyst

In this study, a nickel, nitrogen and oxygen co-doped nanocatalyst (Ni–N/Cox) was prepared and the catalyst exhibited excellent 2e− ORR activity under alkaline condition with a remarkable selectivity for hydrogen peroxide of up to 96%.

Structure determines performance: isomeric Ti-MOFs for photocatalytic synthesis of hydrogen peroxide.

NH2-UiO-66(Ti) and NH2-MIL-125(Ti) were successfully prepared by using post-synthesis exchange (PSE) and hydrothermal methods, and then these frameworks were tested for photocatalytic hydrogen peroxide production in pure water under visible light. NH2-MIL-125(Ti) exhibits superior activity compared to NH2-UiO-66(Ti) due to its shorter Ti-O bond. In addition, NH2-MIL-125-D (defective) demonstrates a high photocatalytic yield of hydrogen peroxide owing to the presence of defect-rich titanium rich sites.

Sustainable photocatalytic synthesis of hydrogen peroxide from catechol-formaldehyde resin microspheres modulated by nitrogen-doped carbon dots

Nitrogen-doped carbon dots (NCDs-220) modified catechol-formaldehyde resin (CFR) microspheres are prepared for the photochemical catalysis of H2O2 production with long-term cycle stability, high SCC efficiency, and H2O2 selectivity.

Progress and perspectives of Pd-based catalysts for direct synthesis of hydrogen peroxide

In this work, the theoretical basis, catalyst design and in situ application of DSHP are comprehensively summarized. It has certain guiding significance for the design of future catalysts.

Zinc peroxide as a convenient and recyclable source of anhydrous hydrogen peroxide and its application in the peroxidation of carbonyls

This study reports a convenient, safe and recyclable source of anhydrous H2O2 for organic peroxide synthesis. It is based on the generation of H2O2 through the reaction of ZnO2 with H2SO4 and the recycling of ZnO2 from ZnSO4 and 1 wt% H2O2.

CO2-activated graphite felt as an effective substrate to promote hydrogen peroxide synthesis and enhance the electro-Fenton activity of graphite/Fe3O4 composites in situ fabricated from acid mine drainage

CO2-activated graphite felt as an effective substrate to promote hydrogen peroxide synthesis and enhance the electro-Fenton activity of graphite/Fe3O4 composites in situ fabricated from acid mine drainage

Composites of Carbons/Indium Sulfide for Hydrogen Peroxide Production and Water Purification

Photocatalysis enables room temperature synthesis of hydrogen peroxide (H2O2) without any byproducts as well as offering advantages such as low cost, and no release of toxic chemicals [1]. Thus, photocatalysis is an appealing approach for the environmentally friendly synthesis of H2O2. Two-dimensional (2D) layered transition metal chalcogenide (TMC) photocatalysts are good at light harvesting due to their high specific surface area and exhibit excellent optoelectronic properties which make them suitable for environmental remediation and energy production [2]. Metal sulfides have a narrower band gap, which improves their light absorption ability in the visible spectrum. However, they often suffer from low quantum yield and high charge recombination rate. Carbonaceous materials have been proven as very effective co-catalysts with semiconductors at increasing their photoactivity and decreasing recombination rate [3]. The present study focusses on indium sulfide (In2S3) and its composites with carbon nano tubes (CNTs) and carbon quantum dots (CQDs) for H2O2 generation via two-electron oxygen reduction reaction. In2S3, In2S3-CNT and In2S3-CQD are synthesized via hydrothermal method. Structural and optical properties characterized using several techniques such as XRD, Raman, UV-Vis-DRS, PL spectra, SEM, TEM etc. show high crystallinity of In2S3 lattice, good dispersion of carbons on In2S3 lattice, improved light absorption and decrease in recombination rate in In2S3 carbon composites. Photoelectric properties are studied using chronoamperometry, EIS, cyclic voltammetry etc. The In2S3 carbon composites show good stability and lower charge transfer resistance and higher active surface area than pure In2S3. The carbon composite materials show a significantly higher performance than the pure In2S3. In2S3-CQD achieves H2O2 production rate of 634 µM h-1, which is ~ 17 times higher than that of pure In2S3. These composites also show good performance for water treatment with In2S3-CQD removing 93% chromium(VI) and 94% rhodamine B (RhB) from contaminated water upon 2h of irradiation. The mechanism of removal of the impurities is also discussed. In2S3-CQD has shown good results owing to their good light absorption, high specific surface area, and CQDs being able to act as electron reservoir. Keywords : Photocatalysis, Hydrogen peroxide photosynthesis, Advanced Oxidation processes, Wastewater Treatment.

Efficient dual-channel photocatalytic H2O2 evolution and photocatalysis-self-Fenton process on defected carbon doped g-C3N4

The synthesis of hydrogen peroxide from photocatalytic reaction of pure water and oxygen has sparked extensive research, however, most photocatalysts have weak light absorption and fast carrier recombination rates. Herein, a C-doped graphitic carbon nitride g-C3N4 with defects (N vacancies and -C≡N groups) was prepared using a supramolecular preassembly method. The as-prepared photocatalyst (s-B0.3CN) exhibited good H2O2 generation performance (108.4 μM under λ ≥ 420 nm in pure water, 2 h) and efficient degradation of 4-CP in a photocatalysis-self-Fenton process. The structure formed by the C-doped and defects significantly facilitated light absorption and carrier separation, increased the specific surface area of the material and enhanced the adsorption of oxygen. Furthermore, this research contributes the understanding of the mechanisms about photocatalytic H2O2 evolution and photocatalysis-self-Fenton. Simultaneously, dual-channel photocatalytic H2O2 evolution mechanisms (O2 + 2e- + 2H+→ H2O2，2H2O + 2 h+ →H2O2 + 2H+) of s-B0.3CN under irradiation were demonstrated.

Atomically Dispersed Fe Motif‐based Electrocatalysts for Hydrogen Peroxide Synthesis

AbstractThe cathodic two‐electron (2e−) oxygen reduction reaction (ORR) has garnered much attention for electrosynthesis of hydrogen peroxide (H2O2). The transition metal single‐atom catalysts (SACs) with tunable geometry structure and electron layout have displayed promising potential in this process. Notably, atomically dispersed Fe−based electrocatalysts have been recognized as high‐activity yet poor‐selectivity catalysts in 2e− ORR due to the high binding energy with the intermediates to break the peroxy bond into H2O. In this Concept, we briefly review the Fe SAC in 2e− ORR for H2O2 production by introducing their fundamental mechanism, chemical process, experimental advancements, and practical applications. The issues encountered and corresponding suggestions are discussed. The customized and tailored isolated Fe motif could fulfill the high activity, selectivity and stability system for H2O2 synthesis.

The First Application of Palladium–Phosphorus Catalysts in the Direct Synthesis of Hydrogen Peroxide: Reasons for the Promoting Action of Phosphorus

The First Application of Palladium–Phosphorus Catalysts in the Direct Synthesis of Hydrogen Peroxide: Reasons for the Promoting Action of Phosphorus

Single-layer crystalline triazine-based organic framework photocatalysts with different linking groups for H2O2 production

Harnessing solar energy for photocatalytic hydrogen peroxide (H2O2) synthesis represents a pinnacle of environmentally-sensitive and sustainable methodologies. While single-layer crystalline triazine-based organic frameworks (CTFs) are known for their prodigious photocatalytic potential in H2O2 generation, ramifications of the connecting group within the triazine ring (TR) on underlying photocatalytic mechanism warrant deeper exploration. In this study, we simulate three distinct CTFs characterized by different TR linkers: CTF-1 (benzene group (BG)), CTF-2 (horizontally-oriented naphthyl group (NGH)), and CTF-DCN (vertically-oriented naphthyl group (NGV)). These diverse TR linkers profoundly modulate the absorption band edge of CTFs, subsequently dictating the orientation and constitution of the frontier orbitals. Such modulation plays a decisive role in determining the requisite energy for photoexcitation in CTFs, orchestrating the generation and distribution of photo-induced electrons and holes. Remarkably, the NGV linkage imparts CTF-DCN with unparalleled light absorption, superior charge separation efficiency, and the lowest energy barrier for associated reactions. Through this investigation, we illuminate the pivotal influence of TR linkers in sculpting the photocatalytic dynamics of CTFs, providing fresh perspectives for architecting CTFs with amplified photocatalytic prowess in H2O2 synthesis.

Supercritical deposition of mono- and bimetallic Pd and Pt on TiO[formula omitted] coated additively manufactured substrates for the application in the direct synthesis of hydrogen peroxide

In this study we investigated the properties of mono- and bimetallic Pd and Pt deposited via supercritical fluid reactive deposition (SFRD) on TiO2 coated additively manufactured substrates. The focus of this work lies on the suitability of these catalysts for the direct synthesis of H2O2 in the liquid phase. All catalysts produced showed a high activity towards the desired reaction, derived from high productivities towards the desired product. Thereby, the productivity of the different catalysts decreased in the following order: Pd = PdPt > Pt. In agreement with literature, an increase of the Pd loading from 1 to 2 wt.-% led to a decrease in the productivity. Resulting from comparison with productivities from literature, this method indicates a high suitability of the SFRD method for the suggested application. Due to the easy and eco-friendly nature of this deposition method the catalyst production process can be intensified.

Calcium oxide nanoparticles mitigate lead stress in Abelmoschus esculentus though improving the key antioxidative enzymes, nutritional content and modulation of stress markers

Lead (Pb) is thought to be one of most injurious metals on the earth. Lead stress in plants enhances synthesis of highly toxic reactive oxygen species (ROS). During present research, impact of calcium-oxide nanoparticles (CaO-NPs) was observed on antioxidative defense mechanism in Abelmoschus esculentus plants prone to Pb stress. A CRD experiment was employed with 5 replicates having four treatments (T0 = Control, T1 = Pb stress (200 ppm), T2 = CaO-NPs and T3 = Pb + CaO-NPs). Pb-stressed seedlings exhibited decreased root growth, shoot growth, chlorophyll concentration and biomass accumulation. Moreover, higher synthesis of hydrogen-peroxide (H2O2), malondialdehyde (MDA) and electrolyte leakage (EL) resulting in cellular injuries were noted in plants growing in Pb spiked conditions. Similarly, stressed plants showed higher accumulation of total soluble sugar and proline content besides elevated activity of antioxidative enzymes counting catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR) and ascorbate peroxidase (APX). On the contrary side, CaO-NPs alleviated the Pb induced phytotoxicity through improving activity of antioxidative enzymes. The elevated activity of antioxidant enzymes reduced biosynthesis of H2O2 and MDA which was revealed through the increased growth parameters. In addition, CaO-NPs persuaded enhancement in plant defence machinery by decreased chlorophyll deprivation and augmented the uptake of plant nutrients including K and Ca content. Hence, CaO-NPs can be potent regulators of the antioxidative enzymes and stress markers to ameliorate abiotic stresses.

Electronic configuration inversion in CdIn2S4 for efficient photocatalytic hydrogen peroxide generation coupled with selective benzylamine oxidation

Vacancies engineering has sparked a huge interest in enhancing photocatalytic activity, but monovacancy simultaneously conducts as either electron or hole acceptor and redox reaction, worsening charge transfer and catalytic performance. Here, the concept of electronic inversion has been proposed through the simultaneous introduction of surface oxygen and S vacancies in CdIn2S4 (OSv-CIS). Consequently, under mild conditions, the well-designed OSv-CIS-200 demonstrated a strong rate of N-benzylidenebenzylamine production (2972.07 µmol g-1 h-1) coupled with Hydrogen peroxide (H2O2) synthesis (2362.33 µmol g-1 h-1) (PIH), which is 12.4 times higher than that of CdIn2S4. Density functional theory (DFT) simulation and characterization studies demonstrate that oxygen is introduced into the lattice on the surface of the material, reversing the charge distribution of the S vacancy and enhancing the polarity of the total charge distribution. It not only provides a huge built-in electric field (BEF) for guiding the orientation of the charge transfer, but also acts as a long-distance active site to accelerate reaction and prevent H2O2 decomposition. Our work offers a straightforward connection between the atomic defect and intrinsic properties for designing high-efficiency materials.

Photo‐Driven Quasi‐Topological Transformation Exposing Highly Active Nitrogen Cation Sites for Enhanced Photocatalytic H2O2 Production

AbstractHerein, the exposure of highly‐active nitrogen cation sites has been accomplished by photo‐driven quasi‐topological transformation of a 1,10‐phenanthroline‐5,6‐dione‐based covalent organic framework (COF), which contributes to hydrogen peroxide (H2O2) synthesis during the 2‐electron O2 photoreduction. The exposed nitrogen cation sites with photo‐enhanced Lewis acidity not only act as the electron‐transfer motor to adjust the inherent charge distribution, powering continuous and stable charge separation, and broadening visible‐light adsorption, but also providing a large number of active sites for O2 adsorption. The optimal catalyst shows a high H2O2 production rate of 11965 μmol g−1 h−1 under visible light irradiation and a remarkable apparent quantum yield of 12.9 % at 400 nm, better than most of the previously reported COF photocatalysts. This work provides new insights for designing photo‐switchable nitrogen cation sites as catalytic centers toward efficient solar to chemical energy conversion.

Photo-Driven Quasi-Topological Transformation Exposing Highly Active Nitrogen Cation Sites for Enhanced Photocatalytic H2 O2 Production.

Herein, the exposure of highly-active nitrogen cation sites has been accomplished by photo-driven quasi-topological transformation of a 1,10-phenanthroline-5,6-dione-based covalent organic framework (COF), which contributes to hydrogen peroxide (H2 O2 ) synthesis during the 2-electron O2 photoreduction. The exposed nitrogen cation sites with photo-enhanced Lewis acidity not only act as the electron-transfer motor to adjust the inherent charge distribution, powering continuous and stable charge separation, and broadening visible-light adsorption, but also providing a large number of active sites for O2 adsorption. The optimal catalyst shows a high H2 O2 production rate of 11965 μmol g-1 h-1 under visible light irradiation and a remarkable apparent quantum yield of 12.9 % at 400 nm, better than most of the previously reported COF photocatalysts. This work provides new insights for designing photo-switchable nitrogen cation sites as catalytic centers toward efficient solar to chemical energy conversion.

An introductory laboratory class in sonochemistry

This article proposes a substantive scope and scenario of a laboratory class that introduces students to the field of sonochemistry. The class requires only basic laboratory equipment - typical laboratory glassware like graduated pipettes and conical flasks, as well as simple inorganic chemicals. It is designed to acquaint students with fundamental aspects of sonochemistry. In the qualitative aspect, they will conduct and observe some sonochemical reactions like a synthesis of hydrogen peroxide and ultrasound-assisted degradation of toxic chromates(VI) which will demonstrate the indirect consequences of water sonolysis which is the most basic sonochemical reaction, as well as they will illustrate the applications of sonochemistry. In the quantitative aspect, students will learn about how to measure the power of ultrasound and the sonochemical efficiency of the reaction and will conduct experiments allowing for the calculation of these parameters. Finally, an introduction to and demonstration of the sonocatalytic effect is planned. An evaluation system, consisting of a report and test, is also proposed.

The First Application of Palladium–Phosphorus Catalysts in the Direct Synthesis of Hydrogen Peroxide: Reasons for the Promoting Action of Phosphorus

The main reasons for the promoting effect of phosphorus on the properties of Pd–P/ZSM-5 palladium catalysts in the direct synthesis of H2O2 from H2 and O2 under mild conditions are considered based on data from X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and inductively coupled plasma mass spectrometry (ICP MS). It is shown that the introduction of phosphorus into the composition of the catalyst affects the dispersity, the electronic state of palladium in the surface layer, and the surface concentration of phosphate and phosphite ions. An increase in the H2O2 yield is favored by an increase in the dispersion of Pd–P-catalysts, inhibition of the side process of H2O2 decomposition by surface phosphate and phosphite ions, and a decrease in the solubility of hydrogen in solid solutions of phosphorus in palladium.