Catalytic Activity Stability Research Articles

Microporosity and Catalytic Activity for Hydrodesulfurization of Pharmacosiderite Mo4P3O16 Synthesized at a Moderate Temperature.

Pharmacosiderite Mo4P3O16 (Pharma-MoPO) consists of [Mo4O4] cubane unit and [PO4] tetrahedral to form an open framework with a microporous structure similar to that of LTA-type zeolite. Although attractive applications are expected due to its microporous structure and redox-active components, its physicochemical properties have been poorly investigated due to the specificity of its synthesis, which requires a high hydrothermal synthesis temperature of 360 °C. In this study, we succeeded in synthesizing Pharma-MoPO by hydrothermal synthesis at 230 °C, which can be applied using a commercially available autoclave by changing the metal source. Through the study of the solids and liquids obtained after hydrothermal syntheses, the formation process of Pharma-MoPO under our studied synthesis conditions was proposed. Advanced characterizations provided detailed structural information on Pharma-MoPO, including the location site of a countercation NH4+. Pharma-MoPO could adsorb CO2 with the amount close to the number of cages without removing NH4+. Pharma-MoPO exhibited stable catalytic activity for the hydrodesulfurization of thiophene while maintaining its crystal structure, except for the introduction of sulfide by replacing lattice oxygens. Pharmacosiderite Mo4P3O16 was successfully obtained by hydrothermal synthesis at a moderate temperature, and its microporosity for CO2 adsorption and catalytic properties for hydrodesulfurization were discovered.

LaCoO3/SBA-15 as a high surface area catalyst to activate peroxymonosulfate for degrading atrazine in water

An efficient perovskite-based heterogeneous catalyst is highly desired to activate peroxymonosulfate (PMS) for removing organic pollutants in water. A high surface area PMS-activator was fabricated by loading LaCoO3 on SBA-15 to degrade atrazine (ATR) in water. The LaCoO3/SBA-15 depicted better textural properties and higher catalytic activity than LaCoO3. In 6.0 min, atrazine (ATZ) degradation in the selected LaCoO3/SBA-15/PMS system, LaCoO3, adsorption by LaCoO3/SBA-15, sole PMS processes reached approximately 100%, 55.15%, 12.80%, and 16.65 % respectively. Furthermore, 0.04 mg L−1 Co was leached from LaCoO3/SBA-15 during PMS activation by LaCoO3/SBA-15. The LaCoO3/SBA-15 showed stable catalytic activity after reuse. The use of radical scavengers and electron paramagnetic resonance spectroscopy (EPR) demonstrated that ROS such as 1O2, O2•−, •OH, and SO4•− were generated by PMS activated by LaCoO3/SBA-15 owing to redox reactions [Co2+/Co3+, and O2−/O2]. EPR, XPS, ATR-FTIR, EIS, LSV, and chronoamperometric measurements were used to explain the catalytic mechanism for PMS activation. Excellent atrazine degradation was due to high surface area, porous nature, diffusion-friendly structure, and ROS. Our investigation proposes that perovskites with different A and B metals and modified perovskites can be loaded on high surface area materials to activate PMS into ROS.

Microstructures, Optical, magnetic Properties, and photocatalytic activity of magnetically separable and reusable ZnO-Doped Fe3O4/rGO nanocomposite synthesized via green route

We report magnetically-separable, reusable, green-synthesized Fe3O4/rGO/ZnO, as heterogeneous catalyst for photo-Fenton degradation of organic pollutants in aqueous solution under certain treatments. Fe3O4 nanoparticles was green-synthesized using Moringa oleifera leaf extract, while rGO was synthesized utilizing Amaranthus viridis leaf extract. Fe3O4/rGO was composited under sonication treatment. Afterwards, Fe3O4/rGO was doped with ZnO with various concentration of ZnO. X-ray diffraction and selected area electron diffraction showed that Fe3O4 and ZnO had spinel cubic and hexagonal structure, respectively; another phase appeared as Fe2O3 spinel cubic structure. Crystallite size was decreased as the ZnO concentration increased. Morphology image showed almost spherical, non-uniform, and slightly dispersed particle under agglomerated condition, attaching to rGO sheets. The particle size of Fe3O4, Fe3O4/rGO, and Fe3O4/rGO/ZnO is 14.3; 14.1; and 10.4 nm, respectively. Fourier-transform infrared spectra showed metallic functional groups, such as Fe-O and Zn–O at 562–589 and 462–478 cm−1 also suggests nanocomposite formation. However, blue-shift absorption and band gap widening were observed with ZnO addition. Raman spectroscopy revealed the formation as-synthesized GO and rGO. Vibrating sample magnetometer showed that green-synthesized Fe3O4/rGO/ZnO exhibited superparamagnetic properties. Removal efficiency of photodegradation methylene blue was optimal for green-synthesized Fe3O4/rGO/ZnO under sonication treatment, reached 100 % degradation within 180 min for uptake every 30 min. Photodegradation was also analyzed using Langmuir-Hinshelwood kinetic model, resulting rate constant of 24.7 × 10−3 min−1 and half-life time of 28.1 min at optimum treatment. Reusability of photocatalytic activity after 3 cycles showed only a tiny drop in catalytic efficiency. Meanwhile, it possesses high stability in catalytic activity and structure. The green-synthesized Fe3O4/rGO/ZnO potential as an environmentally friendly reusable photocatalyst for wastewater degradation.

Electrospun membranes of diselenide-containing poly(ester urethane)urea for in situ catalytic generation of nitric oxide

Nitric oxide (NO) plays an important role as a signalling molecule in the biological system. Organoselenium-coated or grafted biomaterials have the potential to achieve controlled NO release as they can catalyse decomposition of endogenous S-nitrosothiols to NO. However, such biomaterials are often challenged by the loss of the catalytic sites, which can affect the stability in tissue repair applications. In this work, we prepare a diselenide-containing poly(ester urethane)urea (SePEUU) polymer with Se–Se in the backbone, which is further electrospun into fibrous membranes by blending with poly(ester urethane)urea (PEUU) without diselenide bonds. The presence of catalytic sites in the main chain demonstrates stable and long-lasting NO catalytic activity, while the porous structure of the fibrous membranes ensures uniform distribution of the catalytic sites and better contact with the donor-containing solution. PEUU/SePEUU50 in 50/50 mass ratio has a physiologically adapted rate of NO release, with a sustained generation of NO after exposure to PBS at 37 °C for 30 d. PEUU/SePEUU50 has a low hemolysis and protein adsorption, with mechanical properties in the wet state matching those of natural vascular tissues. It can promote the adhesion and proliferation of human umbilical vein endothelial cells in vitro and control the proliferation of vascular smooth muscle cells in the presence of NO generation. This study exhibits the electrospun fibrous membranes have potential for utilizing as hemocompatible biomaterials for regeneration of blood-contacting tissues.

Insight into role of Co species on NiCo/CeMgAl for ethanol steam reforming: Enhanced activity and resistance to coke

Bimetallic catalysts with unique geometric and electronic structure exhibit high performance compared to that of monometallic counterparts in the ethanol steam reforming (ESR). Herein, NiCo bimetals supported on CeO2 doped MgAl2O4 (NiCo/CeMgAl) with different ratio of Ni/Co were prepared for ESR. The synergies between Ni and Co in catalytic activities and ability to anti-coking were focused. The results demonstrate Co atoms trend to segregate toward the surface and are oxidized synchronously, forming the Ni-CoO hybrid surface. The reduced Ni particles are beneficial to maintain a stable catalytic activity for the C-C bonds scission, and the CoO particles formed by segregation and irreversible oxidation of Co0 are more conducive to activation of H2O, the resulting OH promotes the transformation of CHx species, which significantly reduces the selectivity of CH4 and prevents the formation of filamentous carbon. Controlling Co content and maintaining a stable M/Mδ+ are critical to balance the C-C bond scission reaction and the CH3* conversion reaction on the NiCo bimetallic catalysts. The optimal catalyst 9Ni1Co/CeMgAl shows the ethanol conversion of 93.9 % at TOS of 100 h, and the average rate of coke formation is 0.50 mgc·gcat-1·h−1.

Sustainable 3D-printed β-galactosidase immobilization coupled with continuous-flow reactor for efficient lactose-free milk production

The production of low-lactose and lactose-free milk remains a critical challenge. Novel enzyme immobilization integrated with the flow reactor that could be applied to hydrolyze milk with cost-effectiveness, facilitation, and safety is highly expected. Here, we present a novel continuous-flow bioreactor loaded with β-galactosidase (β-Gal) covalently immobilized 3D-printed scaffolds for the production of lactose-free milk. 3D-printed polylactic acid (PLA) scaffolds modified by self-assembly of polyethyleneimine and sodium hyaluronate layers are rapidly branched with functional groups, followed by covalent immobilization of β-Gal using genipin as the cross-linker. The use of genipin allows efficient and stable immobilization of the enzyme (92.87 % immobilization efficiency), and the immobilized enzyme retains 90.53 % activity after 6th repeated use. Moreover, the 3D-printed scaffolds integrated into the flow reactor perturbed the fluids in the different reactors through directional channels, which improved the internal mass transfer to achieve high catalytic activity (94.20 % lactose hydrolysis efficiency). The lactose residues of milk reacted in the β-Gal flow reactor for 6 and 12 h were 1.87 g dL-1 and 0.38 g dL-1, which fully met the requirements of the national food safety standards for low-lactose and lactose-free milk. Due to the high efficiency of enzyme immobilization and the stable catalytic activity of the reactor, it has a broad application prospect for the production of low-lactose and lactose-free milk and other biocatalytic fields.

Electrospun carbon nanofibers decorated with NiS2-FeS2 used as efficient counter electrode for quantum dot sensitized solar cells

NiS2-FeS2 composite material is uniformly coated on CNFs by a one-step hydrothermal method with carbon nanofibers (CNFs) prepared by the electrostatic spinning method. A composite NiS2-FeS2/CNFs with Ti-mesh substrate counter electrode (NiS2-FeS2/CNFs CE) is prepared by scraping and coating method on a metal titanium mesh and applied to quantum dot sensitized solar cells (QDSSCs). The photoelectric power conversion efficiency of QDSSCs assembled on NiS2-FeS2/CNFs electrode substrate is 9.85%, which is much higher than that of traditional Cu2S/brass (7.85%). The exceptional achievement can be attributed to the superb amalgamation of the Ti-mesh's excellent electrical conductivity and the NiS2-FeS2/CNFs nanostructure's high and stable catalytic activity. The co-loading of NiS2 and FeS2 reduces the particle size of the composite, enhancing the specific surface area of the counter electrode. It provides abundant catalytic active sites for QDSSCs. The experimental results show that NiS2-FeS2 is expected to be a competitive and efficient QDSSCs CE material.

Evaluating bimetallic Ni-Co oxygen carriers for their redox behavior and catalytic activity toward steam methane reforming

This work deals with the synthesis of bimetallic Ni-Co oxygen carriers with ZrO2 as structure stabilizer via a one-pot sol–gel auto-combustion method and the evaluation of their redox properties and catalytic activity of their reduced state for steam methane reforming. Fresh materials were composed of Ni-Co mixed monoxides, which could be reduced to form a Ni-Co alloy. Conducting reforming experiments for 10 h time-on-stream at 650 °C showed that Ni-Co alloy sites of reduced bimetallic materials, in addition to the high reforming activity, can improve the stability compared to Ni sites of a monometallic material, due to a higher tendency of the latter toward sintering and coke formation. Redox behavior was tested via CH4 reduction and air oxidation cycles in a thermogravimetric analyzer. Increasing the Co content led to a slight decrease of reduction degree, which, however, was not altered over cycles. Both reduction and oxidation steps were found to proceed via a nucleation and nuclei growth reaction mechanism, with Co addition promoting the oxidation kinetics. Ultimately, addition of Co with low Co/(Ni + Co) ratios (≤0.20) could balance adequate degree of reduction (≥80 %) and oxygen transfer capacity (≥0.07 g O/g material) in tandem with stable catalytic activity for steam methane reforming in the reduced state of oxygen carrier.

Ce1−xSnxO2 Catalysts Prepared with Combustion Method for Catalytic Combustion of Ethyl Acetate

A series of Ce1−XSnXO2 (X = 0, 0.2, 0.3, 0.4, 0.5, 0.9, 1) catalysts were synthesized via the combustion method. The physical and chemical structures of the prepared catalysts were systematically characterized by XRD, BET, SEM, TEM, XPS, and TPR. The Ce1−XSnXO2 catalysts have higher catalytic activities than the mono-oxide catalysts, as there are synergistic effects between CeO2 and SnO2. The catalytic activities of the Ce1−XSnXO2 catalysts are dependent on the X for the catalytic combustion of ethyl acetate (EA). The Ce1−XSnXO2 (X < 0.5) catalysts show high catalytic performances. Meanwhile, the Ce0.8Sn0.2O2 and Ce0.7Sn0.3O2 catalysts display the highest catalytic performance, with T50 = 190 °C and T90 = 210 °C. More importantly, the Ce0.8Sn0.2O2 catalyst exhibits superior thermal and catalytic activity stability. It is found that the Ce1−XSnXO2 catalysts form solid solutions, as the X is <0.5. The reduction of Sn4+ species to Sn2+ is significantly promoted by the CeO2, which is an important factor attributed to the high catalytic activities of the solid solution Ce1−XSnXO2 catalysts. The catalytic activities of the Ce1−XSnXO2 catalysts exhibit a strong correlation to the surface atomic areas of Ce3+ and Oα (VO). In other words, the higher surface atomic areas of Ce3+ and Oα (VO) are, the higher the catalytic activities will have.

Zr-based Laves phases with nitride/hydride ions for ammonia synthesis

Early transition metal-based intermetallic compounds, such as ZrV2, ZrMn2, and ZrCr2, can reversibly absorb large amounts of hydrogen and are of great interest for hydrogen storage. The dissociative hydrogen chemisorption can proceed easily on the surface, allowing the rapid formation of intermetallic hydrides. In this study, we present the results of initial NH3 activity tests conducted on various Zr-based AB2-type intermetallic compounds, free of precious transition metals and rare earth metals. A dissociative hydrogen chemisorption together with nitrogen storage proceeds on AB2-type Laves phase intermetallic compounds accompanied by a lattice expansion. The formed intermetallic nitride hydride ZrCr2N0.4H1.4 exhibits stable catalytic activity as an ammonia synthesis catalyst.

Stable and selective conversion of ethylene to propylene and butylene using Ni-loaded dealuminated Beta zeolite catalyst

The selective conversion of ethylene into propylene (ETP) has garnered significant attention due to the growing demand for the product of this reaction in the petrochemical industry. In this study, we developed a series of Ni-loaded dealuminated Beta zeolite catalysts for the ETP reaction. The catalyst loaded with 0.07 wt% Ni showed stable and high catalytic activity with 28% propylene yield and 16% butylene yield, despite very low Ni content compared to previously reported catalysts. Temperature-programmed H2 reduction and NH3-desorption analyses showed that the active sites were Ni species grafted onto the defective silanols of dealuminated zeolites.

Toward Self‐Supported Bifunctional Air Electrodes for Flexible Solid‐State Zn–Air Batteries

The demand for flexibility and rechargeability in tandem with high energy density, reliability, and safety in energy‐storage devices to power wearable electronics has translated to significant advances in flexible solid‐state Zn–air batteries (FSZABs) technology. FSZABs using self‐supported bifunctional air electrodes are currently one of the most attractive alternatives to Li‐ion battery technology for next‐generation wearable electronics. Unlike the conventional powder‐based air electrodes, self‐supported bifunctional air electrodes offer higher electron‐transfer rate, larger specific surface area (and catalyst–reactant–product interfacial contact area), mechanical flexibility, and better operational robustness. To realize their potential nonetheless, self‐supported bifunctional air electrodes should have high and stable bifunctional catalytic activity, low cost, and environmental compatibility. This review first summarizes the three typical configurations and working principles of FSZABs. Then, significant development of self‐supported bifunctional air electrodes for FSZABs and efficient synthesis strategies are emphasized. The review concludes by providing perspectives on how to further improve the electrochemical performance of FSZABs and their suitability for next‐generation wearable electronic devices.

Effect of Ni-Co addition on Pd promoted Al2O3 catalysts for dry reforming of methane

This study investigates the effectiveness of x Ni – (5 – x) Co / 5 Pd – Al2O3 (where x=0, 1.25, 2.5, 3.75, and 5) bimetallic catalysts and the influence of the Pd on their activity in the dry reforming of methane. Comprehensive characterization techniques including XRD, TPR, TPD, SEM, TGA, and Raman analysis are employed to examine the catalysts. XRD analysis of the calcined catalysts reveals the presence of multiple oxides such as NiO, CoO, Co3O4, and PdO. The metal-support interaction and the particle sintering of the catalysts depend on the amount of Co loading, for higher Co loadings (> 2.5 wt%) resulted in weakened metal-support interaction as indicated by TPR analysis. Also, the particle sintering was observed with an increase in Co loading observed from SEM and TEM analysis. The activity analysis demonstrates that the 5 Ni / 5 Pd – Al2O3 catalysts exhibit superior performance in terms of both CH4 (59%) and CO2 (64%) conversions, as well as stability, compared to the Ni-Co bimetallic catalyst. The addition of Co leads to decreased activity, Furthermore, TGA analysis indicates minimal carbon deposition on the 5 Ni / 5 Pd – Al2O3 catalyst during the 7-hour activity study. Notably, Raman analysis reveals a lower presence of graphitic carbon on the catalyst, which contributes to its stable catalytic activity. The presence of Pd in the 5 Ni catalyst reduces carbon deposition and enhances its activity. However, in the case of the Ni-Co bimetallic catalyst, the promotional effect of Pd appears to be negligible. Overall, these findings emphasize the promising potential of the 5 Ni / 5 Pd – Al2O3 catalyst for efficient and stable dry reforming of methane.

CoCe composite catalyst for the CH4/CO2 reforming reaction: Synergistic effects between Co and Ce species

The greenhouse gases CH4 and CO2 can be use as feedstock to prepare syngas (CO + H2) by CH4/CO2 reforming reaction, and the syngas can be used to produce high value-added chemicals through Fischer-Tropsch reaction. That is, the CH4/CO2 reforming reaction can provide an effective way to rationally use CO2 and CH4. The CoCe catalysts were prepared by impregnation method and grinding method, respectively, and the physicochemical properties were characterized by H2-TPR, XRD, BET, Quasi in-situ XPS and CO2-TPD. The synergistic effects between Co and Ce species can promote the CH4 and CO2 molecules to be continuously and rapidly activated, so that the CoCe catalysts exhibited good catalytic activity for the CH4/CO2 reforming reaction. The preparation methods can affect the dispersion of the Co species and the thermal stability of the oxygen vacancies on the CoCe catalysts to affect catalytic activity. The impregnation method is conducive to the Co species dissolving into the CeO2 lattice to form oxygen vacancies with high thermal stability, and the Co species on the CeO2 surface were in a highly dispersed state, which can provide more stable catalytic activity centers. Thus, the catalysts prepared by impregnation method displayed superior catalytic performances for CH4/CO2 reforming reaction. And the CH4 and CO2 conversions can reach 43.4% and 29.0% at the reaction temperature of 600 °C, respectively.

The enhanced peroxydisulfate activation performance of nitrogen doped biochar encapsulating cobalt in three-dimensional electrochemical system for sulfadiazine removal and mechanism

To boost the peroxydisulfate (PDS) activation performance of biochar (BC) encapsulating cobalt (Co@RBC) in the three-dimensional (3D) electrochemical system, serials N-doped BC encapsulating cobalt (Co@RBC-xN) was prepared using urea as N sourcing and rose petals as biomaterials in this work. Results revealed that N doping can largely promote the PDS activation performance of Co@RBC toward sulfadiazine (SD) degradation in the 3D electrochemical system. The structure-activity relationship analysis revealed that Co0 and sp2-C/sp3-C in catalysts promoted by the doped pyridinic N benefited in strengthening PDS utilization on catalysts surface, thus largely boosting PDS activation efficiency for SD degradation in the system even with a low PDS dosage (0.5 mM). And pyridine N and Co0 were main active sites for PDS activation. Integrating with reactive species trapping experiments and electron paramagnetic resonance (EPR), it revealed that singlet oxygen (1O2), superoxide radical (•O2−) and surface-bounded radicals made main contribution to SD degradation. In addition, the as-prepared Co@RBC-3 N exhibited excellent and stable catalytic activity, good anti-interference of natural water matrices, and easily magnetic separation from solution. This study developed an effective, stable and easily recovery catalysts for PDS activation in 3D electrochemical system and promoted the application possibility of this system for antibiotics removal from wastewater.

Zeolitic Imidazolate Framework-8 Composite-Based Enzyme-Linked Aptamer Assay for the Sensitive Detection of Deoxynivalenol.

The mycotoxin deoxynivalenol (DON) is a prevalent contaminant in cereals that threatens the health of both humans and animals and causes economic losses due to crop contamination. The rapid and sensitive detection of DON is essential for food safety. Herein, a colorimetric biosensor based on horseradish peroxidase- and gold nanoparticle-encapsulated zeolitic imidazolate framework-8 (HRP&Au@ZIF-8) was developed for the sensitive screening of DON. The synthesized HRP&Au@ZIF-8 probes not only held great potential for signal amplification but also exhibited stable catalytic activity even under extreme conditions, which endowed the biosensor with both good sensitivity and stability. Under the optimized conditions, qualitative measurement of DON can be achieved through visual inspection, and quantitative evaluation can be performed via absorbance measurements at a characteristic wavelength of 450 nm. The proposed method has demonstrated high sensitivity with a linear detection range of 1-200 ng/mL and a detection limit of 0.5068 ng/mL. It also presented good selectivity and reliability. Furthermore, DON in spiked cereal samples has been quantified successfully using this method. This novel approach demonstrates significant potential for the facile and expeditious detection of DON in cereal products and brings us one step closer to enhancing food safety.

Degradation of dimethyl phthalate by morphology controlled β-MnO2 activated peroxymonosulfate: The overlooked roles of high-valent manganese species

Activated peroxymonosulfate (PMS) processes have emerged as an efficient advanced oxidation process to eliminate refractory organic pollutants in water. This study synthesized a novel spherical manganese oxide catalyst (0.4KBr-β-MnO2) via a simple KBr-guided approach to activate PMS for degrading dimethyl phthalate (DMP). The 0.4KBr-β-MnO2/PMS system enhanced DMP degradation under different water quality conditions, exhibiting an ultrahigh and stable catalytic activity, outperforming equivalent quantities of pristine β-MnO2 by 8.5 times. Mn(V) was the dominant reactive species that was revealed by the generation of methyl phenyl sulfone from methyl phenyl sulfoxide oxidation. The selectivity of Mn(V) was demonstrated by the negligible inhibitory effects of Inorganic anions. Theoretical calculations confirmed that Mn (V) was more prone to attack the CO bond of the side chain of DMP. This study revealed the indispensable roles of high-valent manganese species in DMP degradation by the 0.4KBr-β-MnO2/PMS system. The findings could provide insight into effective PMS activation by Mn-based catalysts to efficiently degrade pollutants in water via the high-valent manganese species.

A visible light-sensitive argentous oxide/calcium aluminate nanocomposite photocatalyst

A photo-deposition method was developed to synthesise argentous oxide/calcium aluminate nanocomposites (Ag2O-CAONCS) with orthorhombic Ca5Al6O14 and cubic Ag2O phases. Micro-morphology, micro-structure, optical, and visible-light catalytic properties were investigated via different techniques. Ag2O enhances visible-light absorption performance and decreases the band gap of the Ag2O-CAONCS. About 20 mL crystal violet (CV) dye (10 mgL–1) is totally degraded using 20 mg Ag2O-CAONCS under sunlight irradiation for 20 min. The enhanced photocatalytic activity of the Ag2O-CAONCS towards CV under sunlight irradiation is ascribed to the reduction of the band gap, improvement in visible-light absorption and inhibitation role of carriers recombination by Ag2O. The high, stable visible-light catalytic activity makes Ag2O-CAONCS promising photocatalysts for removing organic pollutants.

Nonacid Carbon Materials as Catalysts for Monoethanolamine Energy-Efficient Regeneration.

In the CO2 capture process, solid acid catalysts have been widely adopted to decrease energy consumption in the amine regeneration process owing to abundant acid sites. However, acid sites unavoidably degenerate in the basic amine solution. To address the challenge, nonacid carbon materials including carbon molecular sieves, porous carbon, carbon nanotubes, and graphene are first proposed to catalyze amine regeneration. It is found that carbon materials can significantly increase the CO2 desorption amount by 47.1-72.3% and reduce energy consumption by 32-42%. In 20 stability experiments, CO2 loading was stable with the max difference value of 0.01 mol CO2/mol monoethanolamine (MEA), and no obvious increase in the relative heat duty (the maximum difference is 4%) occurred. The stability of carbon materials is superior to excellent solid acid catalysts, and the desorption performance is comparable. According to the results of theoretical calculation and experimental characterization, the electron-transfer mechanism of nonacid carbon materials is proposed, which is not only beneficial for MEA regeneration but also the probable reason for the stable catalytic activity. Owing to the excellent catalytic performance of carbon nanotube (CNT) in the HCO3- decomposition, nonacid carbon materials are quite promising to enhance the desorption performance of novel blend amines, which will further reduce the cost of carbon capture in the industry. This study provides a new strategy to develop stable catalysts used for amine energy-efficient regeneration.

Three-dimension structural Co-Fe-P/Cu3P derived from the Prussian blue analogue (PBA) grown on nanorods for oxygen evolution reaction

Rational design of non-noble metal electrocatalyst with high stability and activity for OER is desirable for the production of renewable energy to solve the environmental crisis. Starting from Prussian blue analogues (PBAs) with special advantages, the trimetallic hollow structural Co-Fe-P/Cu3P/CF covered with extended nanosheets grown on nanorods was synthesized via ion exchange and calcination approaches in this study. The overpotential of the prepared electrode was only 205 mV at a current density of 100 mA cm− 2, and it can maintain the stable catalytic activity for at least 60 h. The prominent electric performance is mainly attributed to the construction of the unique morphology, in which the rod-shaped structure can promote the transportation of the reactants, and the hollow structure as well as the nanosheets outside can expand the specific surface area. The electronic interaction between multiple metals can also improve the conductivity of the catalyst. The characterization analysis of the post electrode after long-term oxygen evolution reaction imply that the surface of the catalytic electrode was partially oxidized to the corresponding oxide, which can generate the new active sites to maintain the high catalytic activity together with the residual phosphide. Our research might provide a new reference for the deep exploration of PBA-based materials applied in electrochemical energy conversion and storage.