2O3 Catalyst Research Articles

Synergistic effects of NiPtCo/Ti0.7W0.3O2 hybrid electrocatalysts for accelerating formic acid electro-oxidation performance.

We herein report the fabrication strategy of a robust catalyst for the formic acid electro-oxidation reaction (FAOR) via combining the advantages of a TiO2-related support and the synergistic effects of NiPtCo alloy. With the predominant dehydrogenation pathway, the NiPtCo/Ti0.7W0.3O2 catalyst shows remarkable FAOR mass activity and specific activity of 0.45 A mgMetal-1 and 1.25 mA cm-2, being 3.75- and 4.81-time higher than those of the commercially available Pt/C, respectively. The as-made FAOR electrocatalyst shows superior CO-tolerance and electrocatalytic stability during long-term operation conditions due to the synergistic contributions of each component in the overall catalyst system.

Production of Branched Alkanes by Upcycling of Waste Polyethylene over Controlled Acid Sites of SO4/ZrO2-Al2O3 Catalyst.

Branched alkanes, which enhance the octane number of gasoline, can be produced from waste polyethylene. However, achieving highly selective production of branched alkanes presents a significant challenge in the upcycling of waste polyethylene, and the maximum selectivity for branched alkanes reported up to date is about 70%. Here, we report a one-pot process to convert polyethylene into gasoline-range hydrocarbons (C4-C13) with yield of 73.3% over SO42-ZrO2-Al2O3 catalyst at 280 °C. The proportion of branched alkanes reaches 90.1% within the C4-C13 fraction. Incorporation of sulfate group endows the catalyst with strong Lewis acid sites and weak and moderate Brønsted acid sites. In situ X-ray absorption, in situ infrared spectroscopy, in situ small angle neutron scattering, and DFT calculations reveal that polyethylene activation occurs through the synergy between sulfate groups and strong Lewis acid sites (Zr sites). The weak and moderate Brønsted acid sites preferentially catalyze the isomerization and type A β-scission processes, which favors the formation of branched alkanes, while suppressing competing reactions that produce straight-chain alkanes.

Regulation of Oxide Pathway Mechanism for Sustainable Acidic Water Oxidation.

The advancement of acid-stable oxygen evolution reaction (OER) electrocatalysts is crucial for efficient hydrogen production through proton exchange membrane (PEM) water electrolysis. Unfortunately, the activity of electrocatalysts is constrained by a linear scaling relationship in the adsorbed evolution mechanism, while the lattice-oxygen-mediated mechanism undermines stability. Here, we propose a heterogeneous dual-site oxide pathway mechanism (OPM) that avoids these limitations through direct dioxygen radical coupling. A combination of Lewis acid (Cr) and Ru to form solid solution oxides (CrxRu1-xO2) promotes OH adsorption and shortens the dual-site distance, which facilitates the formation of *O radical and promotes the coupling of dioxygen radical, thereby altering the OER mechanism to a Cr-Ru dual-site OPM. The Cr0.6Ru0.4O2 catalyst demonstrates a lower overpotential than that of RuO2 and maintains stable operation for over 350 h in a PEM water electrolyzer at 300 mA cm-2. This mechanism regulation strategy paves the way for an optimal catalytic pathway, essential for large-scale green hydrogen production.

Mn-Fe Dual-Metal Assemblages on Carbon-Coated Al2O3 Spheres for Catalytic Ozonation Oxidation: Structure, Performance, and Reaction Mechanism.

Catalysts with high catalytic activity and low production cost are important for industrial application of heterogeneous catalytic ozonation (HCO). In this study, we designed a carbon-coated aluminum oxide carrier (C-Al2O3) and reinforced it with Mn-Fe bimetal assemblages to prepare a high-performance catalyst Mn-Fe/C-Al2O3. The results showed that the carbon embedding significantly improved the abundance of surface oxygen functional groups, conductivity, and adsorption capacity of γ-Al2O3, while preserving its exceptional mechanical strength as a carrier. The prepared Mn-Fe/C-Al2O3 catalyst exhibited satisfactory catalytic ozonation activity and stability in the degradation of p-nitrophenol (PNP). Electron paramagnetic resonance (EPR) and quenching experiments reveal that radical ( ⋅ OH and ⋅ O2 ⋅ ) and nonradical oxidation (1O2) dominated the PNP degradation process. Theoretical calculations corroborated that the anchored atomic Fe and Mn sites regulated the local electronic structure of the catalyst. This modulation effectively promoted the activation of O3 molecules, resulting in the generation of atomic oxygen species (AOS) and reactive oxygen species (ROS). The economic analysis on Mn-Fe/C-Al2O3 revealed that it was a cost-competitive catalyst for HCO. This study not only deepens the understanding on the reaction mechanism of HCO with transition metal/carbon composite catalysts, also provides a high-performance and cost-competitive ozone catalyst for prospective application.

Scalable Atomic-Layer Tailoring of Abundant Oxide Supports Unlocks Superior Interfaces for Low-Metal-Loading Dehydrogenation.

Liquid organic hydrogen carriers (LOHCs) offer a promising solution for global hydrogen infrastructure, but their practical application faces two key challenges: sluggish dehydrogenation processes and the reliance on catalysts with high noble metal loadings. This study presents a scalable approach to reduce noble metal usage while maintaining high catalytic activity. We synthesized an ultralow Pt content (0.1 wt%) catalyst using γ-Al2O3-based pellet support with atomic layer deposition (ALD) of TiO2. Advanced characterization techniques reveal that the thin ALD-TiO2 shell provides a heterogeneous interface, confining electronically rich Pt-nanoparticle ensembles. The catalyst outperforms both equivalent Pt-content catalysts and a commercial 0.5 wt% Pt/γ-Al2O3 catalyst in homocyclic LOHC dehydrogenation. This study provides insights into the beneficial role of ALD-engineered interfaces for catalytic supports and offers an efficient approach for scalable production of low-noble-metal-content catalysts, with implications for various catalytic processes.

Insights into the effect of various supports on hydrothermal liquefaction of food waste over iron-oxide nano-catalysts

This work investigates the effect of supported iron-oxide nano-catalysts for hydrothermal conversion of food waste. The studied supports were Vulcan carbon (VC), CeO2, ZSM-5 and amorphous SiO2-Al2O3. Catalytic hydrothermal liquefaction experiments were carried out in a batch reactor at 16 MPa and 300 °C maintained for 1 h. Different fractions of Fe(0), Fe2+ and Fe3+ alter its tendency toward deoxygenation, hydrogenations and condensation reactions, which influence the bio-crude yield, elemental compositions, and energy recoveries. The fresh and spent catalysts were characterized using X-ray photoelectron spectroscopy, physisorption analysis, thermogravimetric analysis, transmission and scanning electron microscopy. It was found that the change in catalyst support influences HTL pathways and product compositions. The results reveal that the inclusion of FeOx catalyst on Vulcan carbon, SiO2-Al2O3 and ZSM-5 supports can increase the bio-crude yield by ~7–9 wt% compared to their FeOx-free yields. The increase in bio-crude yield was associated with the decrease in the surface ratios of Fe3+/Fe2+ at the range of 0.8–1.6. In overall, catalysts that had higher tendencies in converting amines into oil-soluble compounds increased the bio-crude yield, while catalysts that promoted dehydration and decarboxylation route decreased the bio-crude yield. The maximum energy recovery in bio-crude was obtained using FeOx/SiO2-Al2O3 catalyst with values ~95 %. The deactivation of catalysts was associated with the increase in Ca and P poisonous elements on catalytic sites, which decreased the energy recovery of recycled FeOx/SiO2-Al2O3 to ~85 % after three cycles.

Optimization of Sol-Gel Catalysts with Zirconium and Tungsten Additives for Enhanced CF4 Decomposition Performance.

This study investigated the development and optimization of sol-gel synthesized Ni/ZrO2-Al2O3 catalysts, aiming to enhance the decomposition efficiency of CF4, a potent greenhouse gas. The research focused on improving catalytic performance at temperatures below 700 °C by incorporating zirconium and tungsten as co-catalysts. Comprehensive characterization techniques including XRD, BET, FTIR, and XPS were employed to elucidate the structural and chemical properties contributing to the catalyst's activity and durability. Various synthesis ratios, heat treatment temperatures, and co-catalyst addition positions were explored to identify the optimal conditions for CF4 decomposition. The catalyst composition with 7.5 wt% ZrO2 and 3 wt% WO3 on Al2O3 (3W-S3) achieved over 99% CF4 decomposition efficiency at 550 °C. The study revealed that the appropriate incorporation of ZrO2 enhanced the specific surface area and prevented sintering, while the addition of tungsten further improved the distribution of active sites. These findings offer valuable insights into the design of more efficient catalysts for environmental applications, particularly in mitigating emissions from semiconductor manufacturing processes.

Bi-functional active sites Cu/MgO-La2O3 catalysts the selective hydrogenation of furfural to furfuryl alcohol

Selective hydrogenation of biomass with high efficiency to produce fine chemicals has high economic value and research significance. The Cu/MgO-La2O3 catalyst exhibits distinct active sites that facilitate the selective hydrogenation of furfural to furfuryl alcohol. Under optimal reaction conditions (90℃, 70 min) with the Cu/MgO-La2O3-6 catalyst, furfural conversion and furfuryl alcohol selectivity exceed 99.9 %. The catalyst’s activity remained approximately 97.6 % after five cycles. The combination of catalytic data, characterization tests, and density functional theory (DFT) calculations confirms that the addition of La promotes Cu reduction, resulting in a structured arrangement of highly hydrogenated copper sites (activation H2) and strongly adsorbed lanthanum sites (adsorbed furfural). Mechanistic studies indicate that the two active sites can simultaneously activate hydrogen and furfural. The strong adsorption of furfural enhances the hydrogenation reaction, while the weak adsorption of furfuryl alcohol inhibits side reaction pathways, thus achieving excellent catalytic selectivity.

Low-temperature and in-situ regenerable ozone decomposition in aircraft with zeolite-encapsulated manganese-oxo cluster catalyst

Eliminating Ozone (O3) in aircraft cabin via catalytic decomposition is of vital importance to passenger health and oil tank anti-explosion. However, commercial catalysts work constantly at high temperature and need take-out regeneration after deactivation, causing high energy consumption and tedious maintenance. Here we attempt to address this issue by developing a manganese-oxo cluster encapsulated zeolite with initial wetness impregnation and microwave drying coupled method. Time-dependent O3 decomposition test show that the efficiency on the optimized sample was kept over 95 % for 98 h at low-temperature (−5 °C) and superhigh space velocity (720000 h−1), and well reproduced after mild regeneration (180 °C by air for 1 h, the lowest temperature for reversible regeneration of O3 catalyst reported ever). Combined EXAFTS, XPS, and DFT calculations reveal the mechanism: luxuriant charge transfer path within the [Mn3O3]n+ cluster accommodated in FAU supercage facilitates the allocation of electrons released from the rate-controlling step, rendering lower barrier energy and stabilized state of manganese for O3 decomposition. An application strategy of “cold air direct-processing and periodic in-situ regeneration” was patterned by robust performance on washcoated structured catalysts. This work affords new insights for upgrading aircraft O3 decomposition and presents metal-oxo zeolite as a platform to tailor practical catalysts.

Dehydrogenation of n-butane to butadiene-1,3: 3. Kinetics of regeneration of coked aluminochromium catalyst

The kinetics of coke burning off at temperatures of 525–650 °C on a K-CrOx/γ-Al2O3 catalyst for single-stage dehydrogenation of n-butane to butadiene-1,3, similar to the industrial one, was studied. It was shown that under the studied conditions, the coke burning off reaction is described by a first-order kinetic equation with respect to oxygen and coke with an observed activation energy of ~93 kJ/mol. The adequacy of the kinetic model was confirmed by the coincidence of the calculated and experimental results.

Selective Hydrogenolysis Conversion of Polyethylene into Alkyl Oil Over Iridium-based Catalyst.

Plastic not only brings convenience but also places a great burden on the environment. Utilizing plastic as a low-cost feed-stock for producing valuable chemicals and fuels is one of the most attractive directions. Among the huge types of plastics, polyolefins (PO), especially polyethylene (PE), were the most abundant type and the most difficult to upgrade. Hydrocracking and hydrogenolysis operate at relatively low reaction temperatures which show promising applications. Herein, Iridium-based catalysts were developed and proved to be effective in PE hydrogenolysis under relatively mild conditions. Catalysts were characterized by TEM, HRTEM, SEM, HAADF-STEM, XPS, CO chemisorption and H2 chemisorption etc. The Ir catalysts showed similar reactivity but better selectivity for liquid products than Ru under similar conditions. A highest 92.7 % percent of liquid products could be obtained under 250 °C, 3 MPa of H2 in 8 hours with Ir/γ-Al2O3 catalyst. The support could also affect the performance, including Lewis acid amount, surface areas, and morphology. And we suppose Iridium catalysts could serve as another choice for plastic hydrogenolysis under mild conditions.

Physical and chemical characteristics and activity of nickel-modified cobalt-iron-containing catalysts in the reaction of dry reforming of methane

In the process of dry reforming of methane (DRM), the activity of low-percentage catalysts based on cobalt and iron oxides and their modification with nickel oxide was studied. It has been established that the addition of nickel oxide into the Fe2O3/γ-Al2O3 catalyst increases the degree of methane conversion from 14 to 89%, and also increases the yield of target reaction products H2 to 43.0 vol.%, CO to 46.1 vol.% at 850 °C. On a Co3О4-NiО/γ-Al2O3 catalyst at 850 °C, methane conversion reaches to 88.1%, the yield of H2 and CO is 44.8%. TPR-H2 analyzes showed that the introduction of nickel oxide into Fe2O3/γ-Al2O3 composition, in contrast to the Co3O4/γ-Al2O3 catalyst, the temperature peaks of Fe2O3-NiО/γ-Al2O3, reduction shift towards lower temperatures and weaken the interaction of metals with the support - γ-Al2O3 and thereby the amount of active reduced particles of iron and nickel oxides increases, which ensures good catalytic activity of Fe2O3-NiО/γ-Al2O3. According to the XRD results, spinel-like form - NiFe2O4, NiAl2O4 and CoAl2O4, also phase as Fe2O3 were obtained on the Fe2O3-NiО/γ-Al2O3 catalyst. This indicates that the developed catalysts form new phases that are active at high temperatures to produce synthesis gas in reduction-oxidation processes during the DRM reaction.

COMPARATIVE STUDY USING CFD OF COUNTER-CURRENT AND CO-CURRENT HYDROTREATING REACTORS USING JATROPHA CURCAS L VEGETABLE OIL

In this work, mathematical modeling and CFD simulation of two countercurrent and cocurrent hydrotreatment reactors were carried out, validating the results with a drained bed reactor (TBR), a commercial CoMo/γ-Al2O3 catalyst was used, the material the raw material was Jatropha Curcas L vegetable oil. The operating conditions were temperature 380 ° C, pressure 8 MPag. The kinetic model that was used considered 13 reactions that involve processes of decarboxylation, decarbonization, hydrodeoxygenation and hydrocracking reactions for triolein and tristearin triglycerides. The CFD simulation was carried out in Fluent 18.2 in a transient state and in 3D, considering the standard κ - ε turbulence models, Eulerian multiphase model and porous medium model, it was shown that the countercurrent reactor has less pressure drop than the countercurrent, the conversion the countercurrent reactor has a greater conversion of reactants of 99%, the generation of products from the countercurrent reactor has higher concentrations than the cocurrent reactor, this is because it has more contact areas between phases in the reactor.

Promoting Surface Reconstruction in Spinel Oxides via Tetrahedral-Octahedral Phase Boundary Construction for Efficient Oxygen Evolution.

Understanding the origin of surface reconstruction is crucial for developing highly efficient lattice oxygen oxidation mechanism (LOM) based spinel oxides. Traditionally, the reconstruction has been achieved through electrochemical procedures, such as cyclic voltammetry (CV), linear sweep voltammetry (LSV). In this work, we found that the surface reconstruction in LOM-based CoFe0.25Al1.75O4 catalyst was an irreversible oxygen redox chemical reaction. And a lower oxygen vacancy formation energy (EO-V) could benefit the combination of the activated lattice oxygen atoms with adsorbed water molecular. Motivated by this finding, a strategy of phase boundary construction from Co tetrahedral to octahedral was employed to decrease EO-V in CoFe0.25Al1.75O4. The results showed that as the Co octahedral occupancy ratio rose to 64 %, a 3.5 nm-thick reconstructed layer formed on the catalyst surface with a 158 mV decrease in overpotential. Further experiments indicated that the coexistence of tetrahedral-octahedral (O-T) phase would result in lattice mismatch, promoting non-bonding oxygen states and lowering EO-V. Then more active lattice oxygen combined with H2O molecules to generate hydroxide ions (OH-), followed by soluble cation leaching, which enhanced the reconstruction process. This work provided new insights into the relationship between the intrinsic structure of pre-catalysts and surface reconstruction in LOM-based spinel electrocatalysts.

Catalytic disproportionation of trimethoxysilane to monosilane: Studies on catalyst, kinetics and reactor modeling

Monosilane is an indispensable special gas used in semiconductor, photovoltaic, LED, TFT, and lithium-ion battery industries. In this work, a chlorine-free route for monosilane by the disproportionation of trimethoxysilane (TMS) was investigated with a novel efficient and stable solid alkaline catalytic system composed of γ-Al2O3 supported K2CO3. TMS conversion of 71.6 % and silane selectivity of 97.6 % were obtained on the 15K2CO3/γ-Al2O3 catalyst with a high WHSV of 8 h−1, which could be operated stably over 300 h. Furthermore, the reaction kinetic model was established based on the E-R mechanism and a catalytic pathway was proposed according to kinetic results and DFT calculation. A novel reactive distillation reactor with cascaded condensers for silane production was simulated by using Aspen Plus. The results showed that the energy consumption of TMS disproportionation is much lower than that in TCS disproportionation.

Palladium-Functionalized Nanostructured Nickel-Cobalt Oxide as Alternative Catalyst for Hydrogen Sensing Using Pellistors.

To meet today's requirements, new active catalysts with reduced noble metal content are needed for hydrogen sensing. A palladium-functionalized nanostructured Ni0.5Co2.5O4 catalyst with a total Pd content of 4.2 wt% was synthesized by coprecipitation to obtain catalysts with an advantageous sheet-like morphology and surface defects. Due to the synthesis method and the reducible nature of Ni0.5Co2.5O4 enabling strong metal-metal oxide interactions, the palladium was highly distributed over the metal oxide surface, as determined using scanning transmission electron microscopy and energy-dispersive X-ray investigations. The catalyst tested in planar pellistor sensors showed high sensitivity to hydrogen in the concentration range below the lower flammability limit (LFL). At 400 °C and in dry air, a sensor response of 109 mV/10,000 ppm hydrogen (25% of LFL) was achieved. The sensor signal was 4.6-times higher than the signal of pristine Ni0.5Co2.5O4 (24.6 mV/10,000 ppm). Under humid conditions, the sensor responses were reduced by ~10% for Pd-functionalized Ni0.5Co2.5O4 and by ~27% for Ni0.5Co2.5O4. The different cross-sensitivities of both catalysts to water are attributed to different activation mechanisms of hydrogen. The combination of high sensor sensitivity to hydrogen and high signal stability over time, as well as low cross-sensitivity to humidity, make the catalyst promising for further development steps.

Reduction and structural modification of MoOx/γ-Al2O3 catalysts through acetic acid treatment for green diesel production from corn distiller’s oil

Enabling new environmentally-friendly resources for fuels and platform chemicals is crucial to fulfill our future energy demands while enhancing circularity. Corn distiller’s Oil (CDO) − as a coproduct of the ethanol industry, serves as a sustainable supply of carbon that may be converted into energy, fuels and specialty chemicals. A current challenge in using renewable oxygenated feedstocks is the high amount of coking and catalyst fouling that occurs. This study examined the hydrothermal deoxygenation of CDO into green diesel using molybdenum oxide (MoOx) catalysts in a continuous process without using any external hydrogen. The possibility of reduction and developing oxygen-deficient surfaces on molybdenum oxide (MoOx) catalysts through acetic acid treatment or adding ceria (CeO2) was investigated in order to enhance the acidity of catalysts as well as catalytic activity and stability required for the production of green diesel from CDO. Results showed that the acidity of these catalysts as measured by NH3 temperature programmed desorption (NH3-TPD) had a strong correlation between the degree of deoxygenation and catalyst stability. Acetic acid treatment of the 7.5 wt% MoO3/γ-Al2O3 catalyst reduced MoO3 to MoO3-x, increased the Mo5+ species from 8.7 % to 22 %, created Mo4+ species and increased the catalyst surface acidity in the range of low to moderate strength by approximately 17 %. The use of acetic acid-treated molybdenum oxide (Hac-7.5 wt% MoO3/γ-Al2O3) catalyst enabled nearly complete (99.9 %) deoxygenation of CDO and heavy hydrocarbons cracking to produce diesel-like fuels. A moderate increase in catalyst surface acidity by acetic acid treatment also increased the selectivity of diesel-like fuel through hydrocracking of long-chain hydrocarbons. This low-cost modification step of catalyst improvement is promising for industrial application. However, cracking of hydrocarbons generated amorphous coke (no graphitic coke was observed) on the catalyst surface, which required periodic removal by controlled calcination of the catalyst in presence of air for further use.

DEVELOPMENT OF AN ENERGY-SAVING TECHNOLOGY FOR THE PRODUCTION OF SYNTHETIC METHANE FROM CARBON DIOXIDE. 1. RESEARCH OF KINETICS AND MACRO-KINETICS OF THE SABATIER REACTION ON MODIFICATIONS OF THE SERIAL NI/Α-AL2O3 CATALYST GIAP-3-6N

This study presents the results of laboratory research of kinetics and mechanisms of heterogeneous catalytic reactions of hydrogenation of carbon dioxide to carbon monoxide and methane through the Sabatier reaction on modifications of the serial Ni/α-Al2O3 catalyst GIAP-3-6N manufactured in Ukraine. The research was carried out on a laboratory bench using a classic glass gradientless reactor with internal piston stirring, which provides kinetic equations at the level of physicochemical constants of the reactions under consideration. A detailed analysis and review of the literature in the areas of kinetic research of our interest was carried out. A detailed comparison of the kinetic parameters obtained by us for the powder (kinetic) form of contact with a nickel content of 7.5 % (NiO = 7.5 %) with a similar and one of the best foreign analogs containing nickel, Katalco 57-4 (NiO = 15−18 %), produced by the British chemical and metallurgical company Johnson Matthey, was performed. The results of the research confirmed almost equal parameters of the kinetic activity of the compared catalysts in the reactions of hydrogenation of carbon dioxide with hydrogen, including the «Sabatier» reaction, which made it possible to propose a similar mechanism of the processes, calculate the reaction rate constants and their activation energy, propose (determine) kinetic equations for design of reactors and processes, both with the loading of a domestic catalyst and its replacement with a foreign analog. Kinetic equations will be used in the development of multi-ton synthesis gas plants for the production of methanol, ammonia, and synthetic methane, as well as carbon-free e-fuel for internal combustion engines that meet modern climate requirements. Bibl. 28, Fig. 4, Tab. 6.

Selective recovery of platinum from spent catalysts to fabricate platinum/amorphous manganese oxide/corrugated silica carrier for formaldehyde removal

The efficient recovery and reutilization of spent Pt catalysts have two huge challenges in the metallurgical and chemical industries. Herein, platinum was selectively retrieved from spent Pt/γ-Al2O3 catalysts by a microwave-assisted aqua regia digestion strategy, and the as-obtained platinum extract was utilized to prepare a novel Pt/amorphous MnOx/corrugated silica carrier (Pt/MnOx/CSC) catalyst for formaldehyde removal. To decrease consumption of toxic aqua regia, the γ-Al2O3 in the spent catalysts was converted to chemically stabile α-Al2O3 via high-temperature calcination. The high Pt leaching efficiency of 98.31% was achieved at a digestion temperature of 110oC and aqua regia concentration of 40vol%. However, the high leaching temperatures and aqua regia concentrations caused the part dissolution of α-Al2O3, and thus decreased the Pt leaching efficiency. The CSC in the Pt/MnOx/CSC catalysts served as a support, while both the Pt nanoparticles and amorphous MnOx microspheres acted as active catalysts. The synergistical effects between the Pt and amorphous MnOx endowed the composite catalysts with excellent catalytic activity, and the HCHO removal efficiency reached 100% even after five cycle tests. On the one hand, the nanostructured MnOx microspheres provided great surface areas and rich oxygen vacancies for heterogeneous catalysis. On the other hand, the Pt nanoparticles not only enhanced the low-temperature reducibilities of MnOx, but also decreased the apparent activation energies of HCHO catalytic oxidation. This work provided a new strategy for the selective recovery of platinum from spent catalysts and the reutilization of Pt-based catalysts for the HCHO thermal catalytic oxidation.

Nickel doped enhanced LaFeO3 catalytic cracking of tar for hydrogen production

The transformation of biomass into green energy was pivotal for sustainable development, yet the efficient conversion of biomass-derived tar into hydrogen-rich syngas remained a significant challenge. This study addressed the catalytic demand for hydrogen production from tar, focusing on the development of LaNixFe1-xO3 perovskites as catalysts. A series of LaNixFe1-xO3 perovskites with varying nickel doping levels (x=0, 0.25, 0.5, 0.75, 1) were synthesized to evaluate their catalytic performance in converting toluene, a representative tar component, into hydrogen. The LaNi0.5Fe0.5O3 catalyst demonstrated the highest hydrogen yield (14.5L/6h) and volume percentage (82.9V/V%), highlighting the optimal nickel doping level for enhancing hydrogen production. The hydrogen production performance of LaNixFe1-xO3 was significantly affected by nickel doping. In particular, a small amount of nickel doping can significantly enhance the hydrogen production capacity of LaFeO3 and maintain good reaction stability. The enhanced performance was attributed to the high oxygen storage capacity of perovskite, which facilitated the removal of surface carbon and promotes the methanation reaction. Notably, the total content of defect oxygen and surface adsorbed oxygen/hydroxyl groups significantly impacted the hydrogen production efficiency. These findings indicated that LaNi0.5Fe0.5O3 was an effective catalyst for converting biomass-derived tar into hydrogen-rich syngas, offering a promising solution to the catalytic demand in the hydrogen production system.