Tuning the selectivity of NH oxidation via cooperative electronic interactions between platinum and copper sites.

Selective catalytic oxidation (SCO) of NH to N is one of the most effective methods used to eliminate NH emissions. However, achieving high conversion over a wide operating temperature range while avoiding over-oxidation to NO remains a significant challenge. Here, we report a bi-metallic surficial catalyst (PtCuO/AlO) with improved Pt atom efficiency that overcomes the limitations of current catalysts.

Near 100% Conversion of Acetylene to High-purity Ethylene at Ampere-Level Current.

Direct production of high-purity ethylene from acetylene using renewable energy through electrocatalytic semi-hydrogenation presents a promising alternative to traditional thermocatalytic processes. However, the low conversion of acetylene results in a significant amount of acetylene impurities in the product, necessitating additional purification steps. Herein, a tandem electrocatalytic system that integrates acetylene electrolyzer and zinc-acetylene battery units for high-purity ethylene production is designed.

Thermally stable high-loading single Cu sites on ZSM-5 for selective catalytic oxidation of NH.

Rigorous comparisons between single site- and nanoparticle (NP)-dispersed catalysts featuring the same composition, in terms of activity, selectivity, and reaction mechanism, are limited. This limitation is partly due to the tendency of single metal atoms to sinter into aggregated NPs at high loadings and elevated temperatures, driven by a decrease in metal surface free energy. Here, we have developed a unique two-step method for the synthesis of single Cu sites on ZSM-5 (termed Cu/ZSM-5) with high thermal stability.

Highly Sensitive Diethylamine Detection at Room Temperature Using g-CN Nanosheets Decorated with CuO Hollow Polyhedral Structures.

Chemiresistive-based metal oxide semiconductor (MOS) gas sensors are widely used in gas sensing due to their advantageous properties. Graphitic carbon nitride (g-CN) and metal oxide heterostructure materials can improve charge transport properties, selectivity, and sensitivity in MOS gas sensor materials. Herein, for the first time, CuO hollow polyhedral structures (HPSs) were synthesized via a hydrothermal technique and annealed at different temperatures, with the 400 °C annealed (CuO-400 HPSs) demonstrating remarkable sensing capabilities for diethylamine (DEA) gas at room temperature (RT).

A Novel Molecularly Imprinted Sensor Based on CuO Nanoparticles with Peroxidase-like Activity for the Selective Determination of Astragaloside-IV.

In this work, dopamine (DA) was polymerized on the surface of CuO nanoparticles (CuO NPs) to form a molecularly imprinted polymer (MIP@PDA/CuO NPs) for the colorimetric detection of astragaloside-IV (AS-IV). The synthesis process of MIP is simple and easy to operate, without adding other monomers or initiators. CuO NPs has high peroxidase (POD)-like activity that can catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to generate oxidized TMB (OxTMB) in the presence of HO, having a maximum ultraviolet-visible (UV-Vis) absorption peak at 652 nm.

Ultrafast Response and High Selectivity of Diethylamine Gas Sensors at Room Temperature Using MOF-Derived 1D CuO Nano-Ellipsoids.

Environmental and health monitoring requires low-cost, high-performance diethylamine (DEA) sensors. Materials based on metal-organic frameworks (MOFs) can detect hazardous gases due to their large specific surface area, many metal sites, unsaturated sites, functional connectivity, and easy calcination to remove the scaffold. However, developing facile materials with high sensitivity and selectivity in harsh environments for accurate DEA detection at a low detection limit (LOD) at room temperature (RT) is challenging.

Cascade NH Oxidation and NO Decomposition via Bifunctional Co and Cu Catalysts.

The selective catalytic oxidation of NH (NH-SCO) to N is an important reaction for the treatment of diesel engine exhaust. CoO has the highest activity among non-noble metals but suffers from NO release. Such NO emissions have recently been regulated due to having a 300× higher greenhouse gas effect than CO.

First-principles calculation of the optical properties of the YBaCuO oxygen vacancies model.

We used first-principles methods to investigate how oxygen vacancy defects affect the optical properties of YBaCuO (0 < < 1), a high-temperature superconductor with potential applications in optical detectors. We calculated the electronic structure of YBaCuO with different amounts of oxygen vacancies at three different sites: Cu-O chains, CuO planes, and apical oxygens. The formation energy calculations support the formation of oxygen vacancies in the Cu-O chain at higher concentrations of vacancy defects, with a preference for alignment in the same chain.

Preparation, performance and mechanism of metal oxide modified catalytic ceramic membranes for wastewater treatment.

Catalytic ceramic membranes (CMs) integrated with different metal oxides were designed and fabricated by an impregnation-sintering method. The characterization results indicated that the metal oxides (CoO, MnO, FeO and CuO) were uniformly anchored around the AlO particles of the membrane basal materials, which could provide a large number of active sites throughout the membrane for the activation of peroxymonosulfate (PMS). The performance of the CMs/PMS system was evaluated by filtrating a phenol solution under different operating conditions.

Integrated Gradient Cu Current Collector Enables Bottom-Up Li Growth for Li Metal Anodes: Role of Interfacial Structure.

3D Cu current collectors have been demonstrated to improve the cycling stability of Li metal anodes, however, the role of their interfacial structure for Li deposition pattern has not been investigated thoroughly. Herein, a series of 3D integrated gradient Cu-based current collectors are fabricated by the electrochemical growth of CuO nanowire arrays on Cu foil (CuO@Cu), where their interfacial structures can be readily controlled by modulating the dispersities of the nanowire arrays. It is found that the interfacial structures constructed by sparse and dense dispersion of CuO nanowire arrays are both disadvantageous for the nucleation and deposition of Li metal, consequently fast dendrite growth.

Elucidating the Roles of Nafion/Solvent Formulations in Copper-Catalyzed CO Electrolysis.

Nafion ionomer, composed of hydrophobic perfluorocarbon backbones and hydrophilic sulfonic acid side chains, is the most widely used additive for preparing catalyst layers (CLs) for electrochemical CO reduction, but its impact on the performance of CO electrolysis remains poorly understood. Here, we systematically investigate the role of the catalyst ink formulation on CO electrolysis using commercial CuO nanoparticles as the model pre-catalyst. We find that the presence of Nafion is essential for achieving stable product distributions due to its ability to stabilize the catalyst morphology under reaction conditions.

Ultrafast short-range catalytic pathway modified peroxymonosulfate activation over CuO with surface oxygen defects for tetracycline hydrochloride degradation.

The presence of antibiotics in water bodies seriously threatens the ecosystem and human health. Advanced oxidation processes (AOPs) based on peroxymonosulfate (PMS), an effective method to remove antibiotics, have a bottleneck problem that the low oxidant utilization is attributed to the hindered electron transfer between metal oxides and peroxides. Here, CuO with rich oxygen vacancies (OVs), MSCuO-300, was synthesized to efficiently degrade tetracycline hydrochloride (TTCH) (k = 0.

A sustainable approach for selective recovery of lithium from cathode materials of spent lithium-ion batteries by induced phase transition.

Recycling of spent lithium-ion batteries (LIBs) has attracted widespread attention because of their dual attributes to environmental protection and resource conservation. Utilization of strong corrosive acids is currently the preferred way to recover valuable metals from spent LIBs, but the extensive use of chemical reagents can pose serious environmental risks. Herein, this research proposes a green process for selective recovery of lithium using the material of spent LIBs itself without adding exogenous reagents, mechanochemistry induced phase transition.

Heterojunctioned CuO/CuO catalyst for highly efficient ozone removal.

In recent years, near surface ozone pollution, has attracted more and more attention, which necessitates the development of high efficient and low cost catalysts. In this work, CuO/CuO heterojunctioned catalyst is fabricated by heating CuO at high temperature, and is adopted as ozone decomposition catalyst. The results show that after CuO is heated at 180°C conversion of ozone increases from 75.

Optimizing the distribution and proportion of various active sites for better NH-SCR property over Cu/SSZ-13.

The Cu/SSZ-13 catalyst with Si/Al ratio of 10 and Cu/Al ratio in the range of 0.005 to 0.5 was synthesized by ion exchange method.

Tailored d-Band Facilitating in Fe Gradient Doping CuO Boosts Peroxymonosulfate Activation for High Efficiency Generation and Release of Singlet Oxygen.

In the field of heterogeneous catalysis, limitations of the surface reaction process inevitably make improving the catalytic efficiency to remove pollutants in water a major challenge. Here, we report a unique structure of Fe surface-gradient-doped CuO that improves the overall catalytic processes of adsorption, electron transfer, and desorption. Interestingly, gradient doping leads to an imbalanced charge distribution in the crystal structure, thereby promoting the adsorption and electron transport efficiency of peroxymonosulfate (PMS).

Uniform Deposition of Li-Metal Anodes Guided by 3D Current Collectors with In Situ Modification of the Lithiophilic Matrix.

The lithium (Li)-metal anode is deemed as the "holy gray" of the next-generation Li-metal system because of its high theoretical specific capacity, minimal energy density, and lowest standard electrode potential. Nevertheless, its commercial application has been limited by the large volume variation during charge and discharge, the unstable interface between the Li metal and electrolyte, and uneven deposition of Li. Herein, we present a 3D host (Cu) with lithiophilic matrix (CuO and SnO) in situ modification via a facile ammonia oxidation method to serve as a current collector for the Li-metal anode.

Multifunctional biomaterials that modulate oxygen levels in the tumor microenvironment.

A characteristic feature of solid tumors is their low oxygen tension, which confers resistance to radiotherapy, photodynamic therapy, and chemotherapy. Therefore, to improve treatment outcomes, it is critical to develop biomaterials capable of targeted modulation of oxygen levels in tumors. In this review, we summarize four types of oxygen-modulating biomaterials, namely, oxygen-carrying biomaterials to deliver oxygen into tumors (e.

Copper oxide/graphitic carbon nitride composite for bisphenol a degradation by boosted peroxymonosulfate activation: Mechanism of Cu-O covalency governs.

Surface structure can govern heterogeneous catalysis, resulting in its critical role in nonradical reactions. Here, we explored whether Cu-O covalency plays a critical role in controlling the inherent properties of copper oxide/graphitic carbon nitride (CuO-CN). Experiments and theoretical calculations show that, in contrast to the traditional concept of low-valent metal control activity, surface modification enlarges Cu-O covalency, and high-valent copper species at the surface easily bind peroxymonosulfate (PMS, (HSO)) anions.

The Electrophilicity of Surface Carbon Species in the Redox Reactions of CuO-CeO Catalysts.

Electronic metal-support interactions (EMSI) describe the electron flow between metal sites and a metal oxide support. It is generally used to follow the mechanism of redox reactions. In this study of CuO-CeO redox, an additional flow of electrons from metallic Cu to surface carbon species is observed via a combination of operando X-ray absorption spectroscopy, synchrotron X-ray powder diffraction, near ambient pressure near edge X-ray absorption fine structure spectroscopy, and diffuse reflectance infrared Fourier transform spectroscopy.

Developmental Hazard of Environmentally Persistent Free Radicals and Protective Effect of TEMPOL in Zebrafish Model.

Environmentally persistent free radicals (EPFRs) can be detected in ambient PM, cigarette smoke, and soils and are formed through combustion and thermal processing of organic materials. The hazards of EPFRs are largely unknown. In this study, we assess the developmental toxicity of EPFRs and the ability of TEMPOL (4-Hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl) to protect against such hazards using zebrafish embryos.

Adsorption and activation of molecular oxygen over atomic copper(I/II) site on ceria.

Supported atomic metal sites have discrete molecular orbitals. Precise control over the energies of these sites is key to achieving novel reaction pathways with superior selectivity. Here, we achieve selective oxygen (O) activation by utilising a framework of cerium (Ce) cations to reduce the energy of 3d orbitals of isolated copper (Cu) sites.

Antibacterial properties and mechanism of biopolymer-based films functionalized by CuO/ZnO nanoparticles against Escherichia coli and Staphylococcus aureus.

In this study, the nanocomposite film (SA-CS@CuO/ZnO) composed of sodium alginate (SA) and chitosan (CS) functionalized by copper oxide nanoparticles (CuONPs) and zinc oxide nanoparticles (ZnONPs) was fabricated, then its antibacterial mechanisms against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were systematically investigated.