Catalysts

21 pages, 2614 KB

Open AccessArticle

Effect of Ba/Ce Ratio on the Structure and Performance of Pt-Based Catalysts: Correlation Between Physicochemical Properties and NOx Storage–Reduction Activity

by Dongxia Yang, Yanxing Sun, Tingting Zheng, Lv Guo, Yao Huang, Junchen Du, Xinyue Wang and Ping Ning

Catalysts 2026, 16(1), 21; https://doi.org/10.3390/catal16010021 (registering DOI) - 26 Dec 2025

Abstract

The continuous tightening of emission regulations and the escalating costs of palladium (Pd) and rhodium (Rh) have renewed interest in platinum (Pt)-based three-way catalysts (TWCs) as cost-effective alternatives for gasoline aftertreatment. However, despite extensive studies on Pt/CeO₂ and Pt/Ba-based formulations, the cooperative [...] Read more.

The continuous tightening of emission regulations and the escalating costs of palladium (Pd) and rhodium (Rh) have renewed interest in platinum (Pt)-based three-way catalysts (TWCs) as cost-effective alternatives for gasoline aftertreatment. However, despite extensive studies on Pt/CeO₂ and Pt/Ba-based formulations, the cooperative roles of Ba and Ce and, in particular, the fundamental influence of the Ba/Ce ratio on oxygen mobility, NO_x storage behavior, and Pt–support interactions remain poorly understood. In this work, we address this gap by systematically tuning the Ba/Ce molar ratio in a series of Pt–Ba–Ce/Al₂O₃ catalysts prepared from Ba(CH₃COO)₂ and CeO₂ precursors, and evaluating their structure–function relationships in both fresh and hydrothermally aged states. Through comprehensive characterization (N₂ physisorption, XRD, XPS, H₂-TPR, NO_x-TPD, SEM, CO pulse adsorption, and dynamic light-off testing), we establish previously unrecognized correlations between Ba/Ce ratio–dependent structural evolution and TWC performance. The results reveal that the Ba/Ce ratio exerts a decisive control over catalyst textural properties, Pt dispersion, and interfacial Pt–CeO₂ oxygen species. Low Ba/Ce ratios uniquely promote Pt–Ce interfacial oxygen and O₂ spillover—providing a new mechanistic basis for enhanced low-temperature oxidation and reduction reactions—while higher Ba loading selectively drives BaCO₃ formation and boosts NO_x storage capacity. A clear volcano-type dependence of NO_x storage on the Ba/Ce ratio is demonstrated for the first time. Hydrothermal aging at 850 °C induces PtO_x decomposition, BaCO₃–Al₂O₃ solid-state reactions forming inactive BaAl₂O₄, and Pt sintering, collectively suppressing Pt–Ce interactions and reducing TWC activity. Importantly, an optimized Ba/Ce ratio is shown to mitigate these degradation pathways, offering a new design principle for thermally durable Pt-based TWCs. Overall, this study provides new mechanistic insight into Ba–Ce cooperative effects, establishes the Ba/Ce ratio as a critical and previously overlooked parameter governing Pt–support interactions and NO_x storage, and presents a rational strategy for designing cost-effective, hydrothermally robust Pt-based alternatives to Pd/Rh commercial TWCs. Full article

(This article belongs to the Section Catalytic Materials)

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17 pages, 2641 KB

Open AccessArticle

Sunlight-Activated Photocatalytic Degradation of Azo Dyes Using Talipariti tiliaceum L.-Mediated Silver Nano-Photocatalyst: A Sustainable Approach to Environmental Remediation

by Suriyakala Gunasekaran, Sathiyaraj Sivaji, Selvam Sathiyavimal, Mohan Kumar Devadas, Kayeen Vadakkan, Chayapol Tungphatthong and Suchada Sukrong

Catalysts 2026, 16(1), 20; https://doi.org/10.3390/catal16010020 (registering DOI) - 26 Dec 2025

Abstract

The main emphasis of the current study is to develop an eco-friendly method for producing silver nanoparticles (AgNPs) using an aqueous flower extract from Talipariti tiliaceum L., and to evaluate the photocatalytic degradation of azo dyes. The synthesized AgNPs were characterized using various [...] Read more.

The main emphasis of the current study is to develop an eco-friendly method for producing silver nanoparticles (AgNPs) using an aqueous flower extract from Talipariti tiliaceum L., and to evaluate the photocatalytic degradation of azo dyes. The synthesized AgNPs were characterized using various spectroscopical and microscopical methods. The photocatalytic capacity of AgNPs was assessed through the degradation of methylene blue (MB) and methyl orange (MO) dye under solar irradiation. The results revealed that the AgNPs were spherical in morphology and 4–15 nm in size. The phytochemical analysis showed that the bioactive compounds from the flower extract aided in the reduction of silver ions to nanoparticles. Both visual observations and spectroscopic methods confirmed the photocatalytic degradation of MB and MO dyes. The degradation processes adhered to a pseudo-first-order kinetic model, demonstrating that photocatalytic activity is time-dependent. In addition, the AgNPs demonstrated stability and reusability through four consecutive cycles with little decline in efficiency. This research contributes significantly to sustainable nanotechnology, offering a practical solution for mitigating water pollution caused by industrial dye discharges. Full article

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16 pages, 4118 KB

Open AccessArticle

Bacteria-Loaded Biochar for Cadmium Immobilization in Aqueous Solutions: Performance and Mechanisms

by Fanfan Ju, Yuyong Wu, Guilei Han, Dajin Liu, Yang Wang, Shaohua Zhang, Kai Yang, Chao Yang and Xinxin Zhao

Catalysts 2026, 16(1), 19; https://doi.org/10.3390/catal16010019 (registering DOI) - 26 Dec 2025

Abstract

The effective remediation of cadmium (Cd) pollution continues to pose a significant challenge in environmental science. Bacteria-loaded biochar (BLBC), a composite material synthesized by immobilizing functional microorganisms onto biochar, has emerged as a promising adsorbent for Cd due to its ability to simultaneously [...] Read more.

The effective remediation of cadmium (Cd) pollution continues to pose a significant challenge in environmental science. Bacteria-loaded biochar (BLBC), a composite material synthesized by immobilizing functional microorganisms onto biochar, has emerged as a promising adsorbent for Cd due to its ability to simultaneously facilitate adsorption and biodegradation. In this study, a manganese (Mn)-oxidizing bacterium (Priestia sp. Z-MLHA-1), isolated from a high-manganese mining area, was successfully used to prepare BLBC. The Cd(II) immobilization performance and underlying mechanisms were systematically investigated. The results showed that bacterial loading significantly optimized the pore structure of the biochar, increasing its specific surface area by 40% and enriching the diversity of surface functional groups. Adsorption experiments demonstrated a strong affinity of BLBC for Cd(II), with a maximum adsorption capacity of 44.17 mg/g. The adsorption behavior followed the Langmuir isotherm and pseudo-second-order kinetic models, indicating a monolayer process dominated by chemisorption. The primary immobilization mechanisms involved complexation with surface oxygen-containing functional groups (e.g., −COOH, −OH), ion exchange, and a synergistic effect between the biochar and the immobilized microorganisms. This material enables efficient Cd(II) removal under environmentally benign conditions, thereby providing a theoretical foundation and technical support for the development of green and sustainable remediation technologies for heavy metal-contaminated water. Full article

(This article belongs to the Section Environmental Catalysis)

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21 pages, 1927 KB

Open AccessReview

Bamboo-Derived Activated Carbon for Dye-Contaminated Wastewater Treatment: A Comprehensive Review of Synthesis, Doping Strategies, and Photocatalytic Performance

by Dhaarisvini Sinnakrishna, Chin Wei Lai, Yue Li, Boon Hoong Ong, Ping Xiang, Irfan Anjum Badruddin, Pooja Dhiman and Amit Kumar

Catalysts 2026, 16(1), 18; https://doi.org/10.3390/catal16010018 - 25 Dec 2025

Abstract

Industrial and domestic effluents contaminated with synthetic dyes represent a significant global environmental and public health concern, necessitating the development of efficient, cost-effective, and sustainable wastewater treatment technologies. Among various remediation strategies, activated carbon (AC) has garnered considerable attention as an effective adsorbent, [...] Read more.

Industrial and domestic effluents contaminated with synthetic dyes represent a significant global environmental and public health concern, necessitating the development of efficient, cost-effective, and sustainable wastewater treatment technologies. Among various remediation strategies, activated carbon (AC) has garnered considerable attention as an effective adsorbent, owing to its high surface area, excellent porosity, and strong adsorption capacity. This review presents a comprehensive analysis of activated carbon, with a particular focus on its derivation from bamboo biomass—a renewable, abundant, and low-cost precursor. It explores the key physicochemical characteristics of bamboo-based AC, common synthesis techniques, and the role of modification strategies—particularly metal oxide doping with TiO₂, ZnO, and MoS₂—in enhancing dye removal performance. The mechanisms underlying dye remediation, including adsorption and photocatalysis, as well as the synergistic effects observed in advanced AC-based composites, are critically examined. Emphasis is placed on the degradation of commonly used textile dyes such as methylene blue (MB), rhodamine B (RhB), and reactive blue, supported by comparative analyses of efficiency, stability, and reusability across various studies. Finally, the review outlines current challenges and knowledge gaps in the field, offering perspectives on future research directions to advance the development and large-scale application of sustainable bamboo-derived activated carbon composites for effective and eco-friendly wastewater purification. Full article

(This article belongs to the Special Issue Next-Generation Catalytic Solutions for Water Purification and Wastewater Remediation)

13 pages, 2037 KB

Open AccessArticle

Photocatalytic 3D ZnO Nanostructures Prepared by Atomic Layer Deposition from a Sacrificial Cellulose Template

by Rafaela Radičić, Maria Kolympadi Markovic, Robert Peter, Ivna Kavre Piltaver, Krešimir Salamon and Gabriela Ambrožić

Catalysts 2026, 16(1), 17; https://doi.org/10.3390/catal16010017 - 25 Dec 2025

Abstract

Three-dimensional ZnO structures were prepared by both thermal atomic layer deposition (ThALD) and plasma-enhanced atomic layer deposition (PEALD) on a sacrificial cellulose template. The synthetic approach consisted of ALD of conformal ZnO nanofilms on the fibrous cellulose template, followed by thermal removal of [...] Read more.

Three-dimensional ZnO structures were prepared by both thermal atomic layer deposition (ThALD) and plasma-enhanced atomic layer deposition (PEALD) on a sacrificial cellulose template. The synthetic approach consisted of ALD of conformal ZnO nanofilms on the fibrous cellulose template, followed by thermal removal of the polymer. The resulting calcinated samples, consisting of a scaffold of fused polycrystalline ZnO nanoparticles, showed a sevenfold and ninefold increase in photocatalytic activity against methyl orange under ultraviolet-A light, for the ThALD and PEALD samples, respectively, compared to the non-calcined samples prior to cellulose removal. In addition to the improved three-dimensional surface exposure and accessible active sites, it was suggested that the amount of hydroxyl groups on the surface and the density of nanoparticle packing in 3D ZnO structures are critical parameters for improving the photoinduced degradation of the dye. Full article

(This article belongs to the Special Issue Synthesis and Catalytic Applications of Advanced Porous Materials)

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14 pages, 4065 KB

Open AccessArticle

Catalytic Decarbonylation of Dimethyl Oxalate to Dimethyl Carbonate on Halogen-Modified Alkali Metal Carbonates in a Fixed-Bed Reactor

by Panhua Zuo, Weihua Shen and Yunjin Fang

Catalysts 2026, 16(1), 16; https://doi.org/10.3390/catal16010016 - 25 Dec 2025

Abstract

The activated carbon (AC) supported alkali carbonate catalysts were investigated for dimethyl oxalate (DMO) decarbonylation to dimethyl carbonate (DMC) in a fixed-bed reactor. Among the tested catalysts, K₂CO₃ supported on AC demonstrated superior performance. Systematic optimization of the preparation conditions [...] Read more.

The activated carbon (AC) supported alkali carbonate catalysts were investigated for dimethyl oxalate (DMO) decarbonylation to dimethyl carbonate (DMC) in a fixed-bed reactor. Among the tested catalysts, K₂CO₃ supported on AC demonstrated superior performance. Systematic optimization of the preparation conditions identified 200 °C and 20 wt% as the optimal calcination temperature and K₂CO₃ loading, respectively, achieving the highest DMO conversion and DMC selectivity. The introduction of KBr as a modifier provided a marked improvement, enhancing DMC selectivity from 83.10% to 89.19%. However, during a 20 h stability test, the 10%KBr + 20%K₂CO₃/AC catalyst exhibited a gradual decline in DMC selectivity. This deactivation is attributed to the leaching of KBr and the formation of potassium oxalate (K₂C₂O₄) via DMO hydrolysis, which is triggered by trace water in the feedstock. Consequently, the trace amount of water in the feedstock would influence both the DMO conversion and DMC selectivity. Full article

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5 pages, 176 KB

Open AccessEditorial

Editorial Catalysts: Catalytic Materials Enabling Sustainable Environmental Remediation and Clean Energy Conversion

by Yuying Hu and Weilin Dai

Catalysts 2026, 16(1), 15; https://doi.org/10.3390/catal16010015 - 25 Dec 2025

Abstract

Amid the escalating global imperatives for energy transition and environmental sustainability, advanced catalytic materials and technologies have emerged as a cornerstone in enabling a low-carbon, circular economy [...] Full article

(This article belongs to the Special Issue Exclusive Papers in Green Photocatalysis from China)

17 pages, 12824 KB

Open AccessArticle

A Theoretical Study of the Reactive Mechanisms of Alkali Metal Doped Ni-Based Oxygen Carrier During Chemical Looping Combustion

by Minjun Wang, Xingyao Nie and Ming Xia

Catalysts 2026, 16(1), 14; https://doi.org/10.3390/catal16010014 - 24 Dec 2025

Abstract

Chemical looping combustion (CLC) is a promising technology for CO₂ capture, with the performance of the system largely dependent on the oxygen carrier. Although Ni-based carriers have been extensively investigated, their practical application is still constrained by inadequate reactivity. This study investigated [...] Read more.

Chemical looping combustion (CLC) is a promising technology for CO₂ capture, with the performance of the system largely dependent on the oxygen carrier. Although Ni-based carriers have been extensively investigated, their practical application is still constrained by inadequate reactivity. This study investigated the doping of alkali metals (Li, Na, K) into NiO to improve its performance in CLC. Through density functional theory calculations, the structural, electronic, and reactivity of doped NiO surfaces were systematically analyzed. Results reveal that doping induces lattice expansion and enhances CO adsorption, with adsorption energies strengthening to −0.53 eV for Li, −0.46 eV for Na, and −0.36 eV for K. Furthermore, alkali metal doping significantly reduces the energy barrier for CO₂ formation from 2.12 eV on pure NiO to 0.73 eV, 0.80 eV, and 0.99 eV on Li-, Na-, and K-doped surfaces, respectively. Oxygen vacancy formation energy also decreases from 3.60 eV to as low as 2.90 eV for K-doping, indicating markedly improved oxygen activity. Electronic structure analysis confirms that doping facilitates electron transfer and stabilizes key reaction intermediates. In conclusion, alkali metal doping substantially enhances the redox activity of NiO, providing an effective strategy for developing high-performance oxygen carriers in CLC. Full article

(This article belongs to the Special Issue Catalysis and Technology for CO₂ Capture, Conversion and Utilization)

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4 pages, 162 KB

Open AccessEditorial

Photocatalytic Nanomaterials for Environmental Purification

by Xiaowang Lu

Catalysts 2026, 16(1), 13; https://doi.org/10.3390/catal16010013 - 24 Dec 2025

Abstract

The accelerating pace of industrialization and continuous population growth have made environmental pollution, particularly of water and air, a severe challenge to global ecosystems and human health [...] Full article

(This article belongs to the Special Issue Photocatalytic Nanomaterials for Environmental Purification)

15 pages, 735 KB

Open AccessArticle

New Anionic Rhodium Complexes as Efficient Hydroboration and Hydrosilylation Catalysts

by Magdalena Jankowska-Wajda, Anna Schulmann, Izabela Dąbek, Błażej Rubiś, Karol Szubert and Hieronim Maciejewski

Catalysts 2026, 16(1), 12; https://doi.org/10.3390/catal16010012 - 23 Dec 2025

Abstract

This paper presents the synthesis and characterization of anionic rhodium(I) complexes obtained by the reaction of a homogeneous Wilkinson catalyst or a rhodium cyclooctadiene dimer with ionic liquids as precursors. All newly produced complexes were characterized spectroscopically (NMR, ESI-MS, FT-IR) and their thermal [...] Read more.

This paper presents the synthesis and characterization of anionic rhodium(I) complexes obtained by the reaction of a homogeneous Wilkinson catalyst or a rhodium cyclooctadiene dimer with ionic liquids as precursors. All newly produced complexes were characterized spectroscopically (NMR, ESI-MS, FT-IR) and their thermal stability was examined (TGA, melting point). Moreover, their catalytic activity was determined in the hydrosilylation of octene or allyl glycidyl ether with 1,1,1,3,3,5-heptamethyltrisiloxane and in the hydroboration reaction of styrene with pinacolborane (HBpin). All catalysts used were insoluble in the reactants, which allowed for their isolation and repeated use. Their activity was compared in subsequent 10 (hydrosilylation) or 5 (hydroboration) catalytic cycles. The obtained results allowed the selection of the most effective catalytic systems, which can be a real alternative to traditional homogeneous catalysts, offering greater ease of recovery and reuse. Full article

(This article belongs to the Special Issue New Development of Catalysts for Organometallic Chemistry)

33 pages, 9239 KB

Open AccessArticle

Ag-Pt/Al₂O₃-WOx Catalysts Supported on Cordierite Honeycomb for the Reduction of NO with C₃H₈, CO, and H₂

by Naomi Nalleli González Hernández, José Luis Contreras Larios, Beatriz Zeifert Soares, Gustavo A. Fuentes, María Eugenia Hernández Terán, Ricardo López Medina, José Salmones Blasquez, Deyanira Angeles Beltrán, José Ortiz Landeros, Leticia Nuño Licona and Israel Pala Rosas

Catalysts 2026, 16(1), 11; https://doi.org/10.3390/catal16010011 - 23 Dec 2025

Abstract

Selective catalytic reduction (SCR) of NO using various reducing agents is a critical area of research for mitigating environmental pollution. In this study, the influence of active phase loading was investigated in four bimetallic Pt-Ag/Al₂O₃-WO_x catalysts, one monometallic [...] Read more.

Selective catalytic reduction (SCR) of NO using various reducing agents is a critical area of research for mitigating environmental pollution. In this study, the influence of active phase loading was investigated in four bimetallic Pt-Ag/Al₂O₃-WO_x catalysts, one monometallic Ag/Al₂O₃-WO_x catalyst, and one Pt-Ag/Al₂O₃-WO_x catalyst subjected to high-severity air-SO₂ pretreatment. All catalysts were supported on cordierite monoliths, and their performance in NO SCR was evaluated using H₂, C₃H₈, and CO as reducing agents. An increase in the active phase loading (Pt-Ag/Al₂O₃) from 10.7 wt% to 17.4 wt% resulted in higher conversions of NO, C₃H₈, and H₂, as well as improved N₂ selectivity. However, CO conversion decreased as the active phase loading increased, which was attributed to competitive reduction by H₂, since both reactions occur within the same temperature range (100–200 °C). The presence of N₂O below 6 ppm was observed in some catalysts. Furthermore, higher active phase loadings led to increased carbon deposition; the Ag/Al₂O₃-WO_x catalyst exhibited the highest carbon content (5 wt.). The deposited carbon was identified as ordered graphitic carbon. In the Pt-Ag catalysts, the presence of Ag⁺ and Agⁿδ⁺ species, as well as the Ag° plasmon, was identified by UV-Vis spectroscopy. STEM analysis showed Ag-Pt crystallites with an average size of 24 nm, which may have contributed to the higher NO conversion observed at 350 °C and the improved N₂ selectivity at 100 °C in the Pt-Ag bimetal catalysts, compared to the activity of the Ag/Al₂O₃-WOx catalyst. Full article

(This article belongs to the Special Issue Heterogeneous Catalysis for Environmentally Compatible Reactions and Processes, 2nd Edition)

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21 pages, 4054 KB

Open AccessArticle

Application of Recombinant [NiFe]-Hydrogenase for Sustainable Coenzyme Regeneration

by Renata Vičević, Zrinka Karačić, Maja Milunić, Anita Šalić, Ana Jurinjak Tušek and Bruno Zelić

Catalysts 2026, 16(1), 10; https://doi.org/10.3390/catal16010010 - 23 Dec 2025

Abstract

Hydrogenases are key enzymes in microbial energy metabolism, catalyzing the reversible conversion between molecular hydrogen and protons. Among them, [NiFe]-hydrogenases are particularly attractive for biocatalytic applications due to the oxygen tolerance of several members of this class and their ability to couple hydrogen [...] Read more.

Hydrogenases are key enzymes in microbial energy metabolism, catalyzing the reversible conversion between molecular hydrogen and protons. Among them, [NiFe]-hydrogenases are particularly attractive for biocatalytic applications due to the oxygen tolerance of several members of this class and their ability to couple hydrogen oxidation with redox cofactor regeneration. In this study, a recombinant soluble [NiFe]-hydrogenase from Cupriavidus necator H16 was successfully expressed in Escherichia coli BL21 (DE3), purified, and characterised with a focus on its applicability for NAD⁺ regeneration. Unlike previous studies that primarily used native C. necator extracts or complex maturation systems, this work provides the first quantitative demonstration that an aerobically purified recombinant soluble [NiFe]-hydrogenase expressed in E. coli can function effectively as an NAD⁺ regeneration catalyst and operate within multi-enzymatic cascade reactions under application-relevant conditions. The crude recombinant enzyme displayed a volumetric activity of 0.273 ± 0.024 U/mL and a specific activity of 0.018 ± 0.002 U/mg_cells in the hydrogen oxidation assay, while purification yielded a specific activity of 0.114 ± 0.001 U/mg with an overall recovery of 79.2%. The enzyme exhibited an optimal temperature of 35 °C and a pH optimum of 7.00. Thermal stability analysis revealed rapid deactivation at 40 °C (k_d = 0.4186 ± 0.0788 h⁻¹, t_1/2 ≈ 1.7 h) and substantially slower deactivation at 4 °C (k_d = 0.1141 ± 0.0139 h⁻¹, t_1/2 ≈ 6.1 h). Batch NADH oxidation experiments confirmed efficient cofactor turnover and high specificity towards NADH over NADPH. Finally, integration of the hydrogenase into a one-pot two-enzyme glucose oxidation system demonstrated its capacity for in situ NAD⁺ regeneration, although the reaction stopped after approximately 5 min due to acidification from gluconic acid formation, highlighting pH control as a key requirement for future process optimization. Full article

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25 pages, 2081 KB

Open AccessArticle

Determination of Optimal Conditions of High-Voltage Short-Pulse Electrohydraulic Discharge Influence on Catalytic Cracking of Oil Sludge

by Amangeldy Satybaldin, Sairagul Tyanakh, Raikhan Seitzhan, Murzabek Baikenov, Feng-Yun Ma, Gulzhan Shaimerdenova, Beken Zhandybaev and Gulnur Alpyssova

Catalysts 2026, 16(1), 9; https://doi.org/10.3390/catal16010009 - 23 Dec 2025

Abstract

The paper studied the effect of high-voltage short-pulse electrohydraulic discharge (HVSPED) on the processes of catalytic cracking of oil sludge in order to increase the yield of light hydrocarbon fractions. A set of laboratory experiments was carried out varying the key parameters of [...] Read more.

The paper studied the effect of high-voltage short-pulse electrohydraulic discharge (HVSPED) on the processes of catalytic cracking of oil sludge in order to increase the yield of light hydrocarbon fractions. A set of laboratory experiments was carried out varying the key parameters of HVSPED—discharge voltage, capacitance of capacitor banks and processing time. As a catalyst, the developed nanocomposite catalyst bentonite was used, with nickel packed. The optimal electrophysical parameters of oil sludge treatment by HVSPED were determined, providing the maximum yield of gasoline and kerosene fractions. The effectiveness of HVSPED treatment of oil sludge in the presence of a catalyst was confirmed by DTA–thermogravimetric analysis and chromatographic-mass spectral analysis of the light and middle fractions of the hydrogenate. The proposed approach made it possible to enhance the resource and energy efficiency of oil sludge processing using HVSPED, demonstrating high potential for further industrial application Full article

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11 pages, 1954 KB

Open AccessCommunication

Scalable Electro-Oxidation Engineering of Raney Nickel Toward Enhanced Oxygen Evolution Reaction

by Yutian Ma, Xu Zhang, Li Tong, Quanbin Huang, Junhu Ma, Hongfu Gao, Juan Zhang, Hailong Xi, Yipu Liu and Shiwei Lin

Catalysts 2026, 16(1), 8; https://doi.org/10.3390/catal16010008 - 23 Dec 2025

Abstract

The efficiency and durability of oxygen evolution reaction (OER) catalysts at industrially relevant current high densities are critical determinants of energy consumption and operating cost of alkaline electrolyzers. However, Raney nickel, widely adopted as a commercial electrode, still lacks sufficient intrinsic activity, leading [...] Read more.

The efficiency and durability of oxygen evolution reaction (OER) catalysts at industrially relevant current high densities are critical determinants of energy consumption and operating cost of alkaline electrolyzers. However, Raney nickel, widely adopted as a commercial electrode, still lacks sufficient intrinsic activity, leading to excessive energy consumption. Herein, a facile electro-oxidation engineering strategy with strong industrial compatibility is developed, and constructs a high-performance OER electrode Raney Ni–Fe³⁺ without compromising the inherent stability and scalability. The optimized electrode achieves 100 mA/cm² at a small overpotential of 265.1 mV with a Tafel slope of 36.17 mV/dec. It further demonstrates exceptional durability, remaining stable for at least 100 h at 300 mA/cm². By in situ constructing Fe³⁺-doped NiOOH phases on the Raney Ni framework, the proposed strategy effectively realizes the precise synthesis of high-performance active layers and greatly enhances the intrinsic catalytic activity. This work provides a new perspective for improving alkaline electrolyzer efficiency and contributing to the large-scale advancement of green hydrogen technology. Full article

(This article belongs to the Special Issue Tailored Nanosystems and Nanocatalysts for Photo-/Electrocatalytic Applications, 2nd Edition)

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30 pages, 2783 KB

Open AccessReview

Progress in Metal Oxide Catalysts for Carbon Monoxide Oxidation

by Yang Zheng, Hualong Zhou, Wei Su and Yi Xing

Catalysts 2026, 16(1), 7; https://doi.org/10.3390/catal16010007 - 22 Dec 2025

Abstract

As one of the most intensively researched reaction systems in the field of multiphase catalysis, the technological breakthrough of CO oxidation is of great significance in addressing the health hazards and environmental pollution caused by high CO concentrations. Catalytic oxidation technology has become [...] Read more.

As one of the most intensively researched reaction systems in the field of multiphase catalysis, the technological breakthrough of CO oxidation is of great significance in addressing the health hazards and environmental pollution caused by high CO concentrations. Catalytic oxidation technology has become a core means of eliminating CO pollution due to its high efficiency and energy saving. This paper provides an in-depth analysis of various types of metal-catalyzed CO oxidation reactions and explores in detail the characteristics of the action of different mechanisms. On this basis, optimization strategies are proposed, including metal doping and controllable oxygen vacancy construction to enhance reaction selectivity and stability. In addition, the influence mechanisms of common gas components such as H₂O and SO₂ on the catalytic reaction of CO are analyzed, and targeted optimization strategies are proposed. The reaction mechanisms of CO on the metal catalyst surface are then examined. Finally, the development direction of catalysts in the field of CO deep purification is prospectively discussed, which provides theoretical support and technical routes for the construction of an efficient and stable industrialized CO oxidation system. Full article

(This article belongs to the Section Catalytic Materials)

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16 pages, 4364 KB

Open AccessArticle

Study on Crystal Plane Adjustment of Pt/P-CNTs Catalyst and Its Electrocatalytic Performance in Methanol Oxidation

by Wenpeng Zhang, Yan Zhao and Hongwei Li

Catalysts 2026, 16(1), 6; https://doi.org/10.3390/catal16010006 - 22 Dec 2025

Abstract

To improve the electrocatalytic methanol oxidation (MOR) performance of platinum (Pt)-based catalysts in direct methanol fuel cells (DMFCs), this study uses phosphorus-doped carbon nanotubes (P-CNTs) as a support material. Through a hydrothermal method, different proportions of potassium bromide (KBr) are introduced as a [...] Read more.

To improve the electrocatalytic methanol oxidation (MOR) performance of platinum (Pt)-based catalysts in direct methanol fuel cells (DMFCs), this study uses phosphorus-doped carbon nanotubes (P-CNTs) as a support material. Through a hydrothermal method, different proportions of potassium bromide (KBr) are introduced as a structural directing agent to prepare a series of Pt/P-CNTs-M catalysts (where M represents the molar ratio of KBr to Pt). The study systematically investigates the mechanism by which KBr regulates the crystal plane of Pt nanoparticles and its structure–activity relationship. Physical characterization revealed that KBr selectively regulates Pt crystal plane growth through Br⁻ adsorption. When M = 30, Pt/P-CNTs-30 exhibited the highest proportion of exposed Pt(111) crystal planes (27.21%), with Pt⁰ content reaching 51.64%, and featured moderate particle size (2.22 nm) and uniform dispersion. Electrochemical testing indicates that the MOR mass-specific activity of this catalyst reaches 3559.85 mA·mg⁻¹_Pt, which is 1.17 times that of Pt/P-CNTs-0; it exhibits the lowest charge transfer impedance, with a current density of 488.25 mA·mg⁻¹_Pt still maintained after 3600 s of chronoamperometry testing, and a more negative CO oxidation onset potential, demonstrating optimal resistance to poisoning. The study indicates that an appropriate KBr ratio can synergistically optimize Pt crystal plane structure and electronic states, providing a theoretical basis for the design of high-efficiency fuel cell catalysts. Full article

(This article belongs to the Section Electrocatalysis)

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30 pages, 4883 KB

Open AccessReview

Preparation of Biochar-Based Photocatalytic Materials and Their Applications in Water Treatment: A Review

by Qiao Xu, Xiang Li and Yinsong Si

Catalysts 2026, 16(1), 5; https://doi.org/10.3390/catal16010005 - 22 Dec 2025

Abstract

The escalating issue of water pollution has intensified the demand for efficient remediation technologies. Biochar adsorption and photocatalytic degradation have emerged as promising approaches for water treatment, with each offering distinct advantages. Integrating these two strategies into biochar-based photocatalytic composites presents a novel [...] Read more.

The escalating issue of water pollution has intensified the demand for efficient remediation technologies. Biochar adsorption and photocatalytic degradation have emerged as promising approaches for water treatment, with each offering distinct advantages. Integrating these two strategies into biochar-based photocatalytic composites presents a novel and effective pathway for advanced water purification. This review systematically summarizes recent advances in the preparation of biochar, modification of photocatalysts, and synthesis techniques for their integration. Furthermore, we critically examine the current application landscape and key challenges facing biochar-based photocatalytic materials in water treatment. Promising future research directions are outlined along with identifiable bottlenecks that must be addressed to advance the field. This work aims to offer insightful perspectives and practical guidance for the rational design and development of high-performance biochar-based photocatalytic systems. Full article

(This article belongs to the Special Issue Recent Advances in Photocatalytic Treatment of Pollutants in Water, 2nd Edition)

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3 pages, 121 KB

Open AccessEditorial

Catalysis on Zeolites and Zeolite-like Materials, 3rd Edition

by Wladimir Reschetilowski

Catalysts 2026, 16(1), 4; https://doi.org/10.3390/catal16010004 - 22 Dec 2025

Abstract

The scientific and practical interest in catalysts based on zeolites and zeolite-like materials continues to be strong; therefore, this Special Issue of Catalysts, “Catalysis on Zeolites and Zeolite-Like Materials, 3rd Edition,” continues the successful publication of the preceding two volumes [...] Full article

(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials, 3rd Edition)

16 pages, 4741 KB

Open AccessArticle

Study on the Interaction Between Ni²⁺ and SO₄²⁻ on the Surface of ZSM-5 Catalyst and the Effect on n-Butene Oligomerization

by Xi Xu, Guangbo Liu, Jianqing Li, Yurou Gao, Suning Gu and Jinhu Wu

Catalysts 2026, 16(1), 3; https://doi.org/10.3390/catal16010003 - 22 Dec 2025

Abstract

The identification of key active sites that determine oligomerization degree is a key focus of research in olefin oligomerization. The Ni/S-HZSM-5 catalyst has attracted widespread attention due to its excellent performance in this reaction. However, the interaction between SO₄²⁻ and Ni [...] Read more.

The identification of key active sites that determine oligomerization degree is a key focus of research in olefin oligomerization. The Ni/S-HZSM-5 catalyst has attracted widespread attention due to its excellent performance in this reaction. However, the interaction between SO₄²⁻ and Ni²⁺ on the ZSM-5 support, especially quantitatively regulating their ratio, has been rarely investigated. In this study, we prepared a series of Ni/S-HZSM-5-x catalysts by fixing the Ni loading and varying the Ni/S molar ratio in the initial feedstock. Then, the obtained catalysts were characterized to systematically investigate how the Ni/S ratio affects their structure, properties, and n-butene oligomerization performance. The results indicate that tuning the Ni/S ratio enables the targeted regulation of surface acidity and electronic properties of the catalysts. The Ni/S ratio influenced the interaction between the Ni cation and SO₄²⁻-SO₃²⁻ complex, which in turn altered the Lewis acidity of the catalysts. Further evaluation results reveal that n-butene conversion is positively correlated with the catalyst’s acidity, and the Ni²⁺/Ni⁺ ratio is positively correlated with the carbon chain length of the products. The surface form of NiSO₄ is the primary factor determining Lewis acidity, which is directly associated with the chain-growth ability of the catalyst. Full article

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