Efficient Catalyst For Hydrogen Production Research Articles

Synthesis of novel activated carbon-supported trimetallic Pt–Ru–Ni nanoparticles using wood chips as efficient catalysts for the hydrogen generation from NaBH4 and enhanced photodegradation on methylene blue

A novel activated carbon (AC) supported trimetallic Platinum–Ruthenium–Nickel nanoparticles (AC@Pt–Ru–Ni NPs) synthesized as an efficient catalyst for hydrogen production from NaBH4 and enhanced photodegradation ability on methylene blue (MB) dye is reported. AC, which is used as a support material in nanoparticle synthesis, was produced from wood chips. X-ray diffractometry (XRD), atomic force microscope (AFM), Fourier transform infrared spectrophotometer (FTIR), Transmission Electron Microscope (TEM), and UV–visible spectrophotometer (UV–Vis) are used for nanoparticles characterization. According to XRD analysis, the average crystal particle size was measured to be about 3.44 nm. In TEM analysis, the average particle size was determined as 2.44 nm. The photocatalytic activity of AC@Pt–Ru–Ni NPs was examined against MB azo dye and found to have 97% photocatalytic degradation at 300 min against MB. The catalyst activity of AC@Pt–Ru–Ni NPs in hydrogen production was determined by the methanolysis reaction from NaBH4. The Turnover of Frequency (TOF), Activation energy (Ea), enthalpy (ΔH), and entropy values (ΔS) values of the hydrogen production reaction were calculated as 1154.04 h−1, 24.29 kJ/mol, 26.83 kJ/mol, −198.76 J/mol.K, respectively. The study successfully achieved the recycling of wood waste, production of hydrogen, and photodegradation against MB dye. In this study, wood wastes were evaluated and it was aimed to be used in AC production and nanocatalyst synthesis. The efficiency of the synthesized AC@PtRuNi nanocatalyst in hydrogen production and its usability for cleaning dyes from wastewater was determined. The obtained results show that AC@PtRuNi nanocatalyst has potential usability both in hydrogen production and in applications for cleaning dyes from wastewater.

Silk fibroin derived porous carbon aerogels confined hyperdispersed Rh nanoparticles to achieve electrocatalytic hydrogen evolution under high current density

In order to meet the current demand for clean energy and realize industrial application, it is urgent to develop highly efficient catalysts for hydrogen production from electrolytic water. Herein, we successfully synthesize hyperdispersed Rh nanoparticles on silk fibroin derived porous N-doped carbon aerogels (N-Rh/CA) using environment friendly silk fibroin as precursor material. The bonding between Rh and N anchored Rh nanoparticles uniformly super-dispersed on the substrate, exposing plentiful active sites. This N-Rh/CA with ultra-low metal content (2 wt %) exhibits the Pt-like electrocatalytic activity for hydrogen evolution, delivering current density of 10 and 100 mA cm−2 at a ultrasmall overpotential of 65 mV and 210 mV, respectively. Meanwhile, N-Rh/CA possesses a mass activity of 196.81 A g−1 at potential of 150 mV, and exhibits outstanding economic efficiency compared with Pt/C and reported Rh-based electrocatalyst. Furthermore, the electrocatalyst showed superior stability for the hydrogen evolution reaction, paving way for its potential industrial application.

Development of Mo-Modified Pseudoboehmite Supported Ni Catalysts for Efficient Hydrogen Production from Formic Acid.

Formic acid (FA), as a safe and renewable liquid hydrogen storage material, has attracted extensive attention. In this paper, a series of Mo-modified pseudoboehmite supported Ni catalysts were developed and evaluated for efficient hydrogen production from formic acid. Pseudoboehmite (PB) as a catalyst carrier was used for the first time. Ni/PB and NiMo/PB possessed a mesostructure, and the pore size distribution was mainly concentrated between 2 and 20 nm. The oxygen vacancies caused by Mo enhanced Ni anchoring, thus inhibiting Ni sintering. Compared with Ni10/PB (7.62 nm), Ni10Mo1/PB had smaller Ni particles (5.08 nm). The Ni–O–Al solid solutions formed through the interaction of Ni with the PB improved the catalytic performance. Ni10Mo1/PB gave the highest conversion of 92.8% with a H2 selectivity of 98% at 300 °C, and the catalyst activity hardly decreased during the 50 h stability test. In short, Ni10Mo1/PB was a promising catalyst for hydrogen production from formic acid because of the oxygen vacancy anchoring effect as well as the formation of Ni–O–Al solid solutions which could effectively suppress the Ni sintering.

Hydrogen Production from Coal Industry Methane

Coal industry methane is a fossil raw material that can serve as an energy carrier for the production of heat and electricity, as well as a raw material for obtaining valuable products for the chemical industry. To ensure the safety of coal mining, rational environmental management and curbing global warming, it is important to develop and improve methods for capturing and utilizing methane from the coal industry. This review looks at the scientific basis and promising technologies for hydrogen production from coal industry methane and coal production. Technologies for catalytic conversion of all types of coal industry methane (Ventilation Air Methane – VAM, Coal Mine Methane – CMM, Abandoned Mine Methane – AMM, Coal-Bed Methane – CBM), differing in methane concentration and methane-to-air ratio, are discussed. The results of studies on the creation of a number of efficient catalysts for hydrogen production are presented. The great potential of hybrid methods of processing natural coal and coal industry methane has been demonstrated.

In situ reduction of PdO encapsulated in MCM-41 to Pd(0) for dehydrogenation of formic acid

A series of PdO@MCM-41-x was in situ synthesized by a facile one-pot method, and their catalytic performance for dehydrogenation of formic acid was investigated. The PdO nanoparticles were immobilized in MCM-41 channel with small size of 2.2–2.5 nm due to the confinement of mesoporous silica. The initial turnover frequency (TOF) of as-prepared catalyst can reach 1096 h−1 at 323 K with 100% hydrogen selectivity. The hydrogen production activity was better than that of catalyst priorly reduced by hydrogen because of the gradual reduction of PdO nanoparticles and generation of fresh Pd(0) during the formic acid dehydrogenation process, which was confirmed by XPS characterization and catalytic system monitoring. It provides a new way for the preparation of simple and efficient catalysts for hydrogen production, which has great application potential.

Universal low-temperature oxidative thermal redispersion strategy for green and sustainable fabrication of oxygen-rich carbons anchored metal nanoparticles for hydrogen evolution reactions

A simple and green low-temperature oxidative thermal redispersion strategy was developed for obtaining well-distributed Rh, Ru, Ir NPs on oxygen-rich mesoporous carbon with considerable activity toward hydrogen evolution compared with the counterpart without any pre-treatment. • Universal low-temperature oxidative thermal redispersion strategy was developed. • The strategy benefits for well-defined metal NPs anchored on oxygenated carbons. • As-formed AC was a universal carrier for selected Pt group metal (Ru, Rh, Ir) NPs. • Rh/C-300A-350H had the highest HER activity for AB hydrolysis and water splitting. • The small Rh NPs with electron-rich sites contributed to the high HER performance. Supported metal nanoparticles (MNPs) have shown great promise in catalytic hydrogen evolutions because of the highly efficient utilization of metal atoms, while the low binding strength between MNPs and supports results in the agglomeration of MNPs into larger particles, considerably decreasing the catalytic efficiency. Herein, we smartly develop a universal, green, and sustainable low-temperature oxidative thermal redispersion strategy to fabricate metal oxide precursors and subsequently well dispersing and stabilizing MNPs (M = Rh, Ru, Ir) over oxygenated carbons (Mesoporous carbon, Ketjen black, and Vulcan carbon), which can be utilized as efficient catalysts for hydrogen production from ammonia borane (AB) hydrolysis and hydrogen evolution reaction (HER). Such flexible modulation strategy enables the formation of oxidized metal species on oxygenated carbons, which is the key to synthesize ultrasmall MNPs against sintering and agglomeration during the reduction process. Attributing to the innately structural/componential/surficial superiorities, the optimal Rh/C-300A-350H exhibits the highest catalytic activity toward hydrogen evolution from AB hydrolysis and HER with turnover frequencies of 3308/5040 min −1 in aqueous/basic solutions and an overpotential of 29 mV at 10 mA cm −2 in 1.0 M KOH, respectively. With the similar activation mechanism for dissociation of O–H bond in H 2 O, the highly dispersed Rh NPs with ultrafine sizes and electronic metal-support interaction are responsible for the excellent catalytic activity toward the hydrogen evolution reactions. This study presents an extremely facile and sustainable modulation strategy for increasing the adhesion of MNP catalysts on oxygenated carbons for catalytic applications.

Methanol-assisted energy-saving hydrogen production over defect-rich perforated PdIn bimetallene

Thermodynamically favorable oxidation reaction instead of oxygen evolution reaction (OER) with sluggish kinetics as anode reaction and coupled with hydrogen evolution reaction (HER) at cathode is an effective hydrogen production technology. Herein, we report a solvothermal method synthesis of defect-rich crimped perforated PdIn bimetallene as an efficient catalyst for hydrogen production with the assistance of methanol. Boosted by abundant crystal defects, higher surface energy and expanded surface active sites, the defect-rich crimped perforated PdIn bimetallene exhibits superior activity and stability in catalyzing methanol oxidation reaction (MOR) and HER. At the established MOR-HER co-electrolytic system, when the anode and cathode are equipped with PdIn bimetallene, the required cell voltage only is 1.26 V to achieve the current density of 100 mA cm−2, which is 0.93 V lower than that of traditional water electrolysis. This work reports a defect-rich crimped perforated PdIn bimetallene catalyst, as an effective bifunctional catalyst that provides insight for the advancement of energy-saving and promising hydrogen production engineering.

The controlled synthesis of nitrogen and iron co-doped Ni3S2@NiP2 heterostructures for the oxygen evolution reaction and urea oxidation reaction.

At present, global resources are nearly exhausted and environmental pollution is becoming more and more serious, so it is urgent to develop efficient catalysts for hydrogen production. Herein, nitrogen and iron co-doped Ni3S2 and NiP2 heterostructures with high efficiency oxygen evolution reaction (OER) and urea oxidation reaction (UOR) performances were firstly successfully prepared on nickel foam by hydrothermal and high-temperature calcination methods. Benefiting from the hierarchical structure, the exposure of more active sites and the doping effect of N and Fe, the N-Fe-Ni3S2@NiP2/NF material showed excellent electrocatalytic activity for the OER and UOR. The N-Fe-Ni3S2@NiP2/NF material displays excellent catalytic OER performance; the overpotential is only 251 mV to drive 100 mA cm-2 current density, while for the UOR, the potential is only 1.353 V to drive 100 mA cm-2 current density, which is one of the best catalytic activities reported so far. It is worth noting that scanning electron microscopy showed that the surface of N-Fe-Ni3S2@NiP2/NF is rough and has some mesopores, which may have resulted in an increase of active sites during the electrocatalytic process. The N-Fe-Ni3S2@NiP2/NF electrode couple also has relatively long-term durability in alkaline solutions, maintaining a stable current density for 15 h at 1.35 V. The density functional theory (DFT) calculation shows that the in situ generated Fe doped nanooxides exhibit strong water adsorption energy, which may be one of the reasons for the good catalytic activity. Our work is conducive to the rational design of electrocatalysts for efficient hydrogen production from water splitting and wastewater treatment.

Three-dimensional porous cobalt as an efficient catalyst for hydrogen production by NaBH4 hydrolysis

Three-dimensional porous cobalt as an efficient catalyst for hydrogen production by NaBH4 hydrolysis

Mixed-dimensional niobium disulfide-graphene foam heterostructures as an efficient catalyst for hydrogen production

Besides developing a large number of catalysts for hydrogen evolution reaction (HER) in alkaline electrolytes, its conversion efficiency remained low. Herein, we have developed mixed-dimensional heterostructures of niobium disulfide (NbS2) with graphene foam grown on nickel foam (NbS2-Gr-NF). The strong lateral fusion results in activating the catalytic sites of NbS2, the three-dimensional substrate provides easy access of electrolyte to active sites and increased electrochemically active surface area, while enhanced conductivity provides faster transfer of electrons to and from active sites. Therefore, NbS2-Gr-NF heterostructures resulted in an exceptionally high current density of 500 mA cm−2 at a very low overpotential of 306 mV in 1 M KOH solution and even can achieve the current density values of 914 mAcm−2 at 338 mV only at a slight increase in overpotential (32 mV). Moreover, a Tafel value of ~72 mV dec−1 confirms that as-developed heterostructure provides fast reaction kinetics where the reaction is mainly controlled by the Volmer step. Achieving such high current density at a faster rate with high stability makes NbS2-Gr-NF heterostructures a potential candidate for water-splitting, especially in alkaline electrolytes.

Hydrogen generation from methanol with network efficient power control for wireless communication system

This paper presents a numerical and experimental study on the performance of a methanol steam reformer integrated with a hydrogen/air combustion reactor for hydrogen production. The steam methane reforming reaction mechanism essential for the rational design of catalysts for efficient hydrogen production was elucidated. The development of non-precious metal hydrogen evolution catalysts to replace platinum is crucial for efficient hydrogen production. The simulation showed that deep neural network algorithms for fluid-structure topology optimization could improve the control effect. Meanwhile, the system can run stably under conditions close to the theoretical optimum with the reformer, non-precious metal catalysts, and neural network methanol flow control.

Ru Nanoparticles on Pr2O3 as an Efficient Catalyst for Hydrogen Production from Ammonia Decomposition

Ru Nanoparticles on Pr2O3 as an Efficient Catalyst for Hydrogen Production from Ammonia Decomposition

Enhancement effect of catalyst support on indirect hydrogen production from propane partial oxidation towards commercial solid oxide fuel cell (SOFC) applications

Utilization of propane in solid oxide fuel cells (SOFCs) is desired for commercial applications. However, the susceptibility of conventional Ni-based anode to coking is still a technical challenge. Developing an efficient catalyst for hydrogen production through partial oxidation of propane is a feasible approach to address this issue. In fact, hydrogen production from propane partial oxidation is profoundly determined by catalyst performance, which further affects the fuel cell efficiency. In this study, a robust and efficient catalyst is developed by incorporating inexpensive TiO2 into Ni-Co/Al2O3 catalyst. The results suggested that an appropriate amount of TiO2 in catalyst support could regulate the interaction between active metal and Al2O3 support therefore inhibiting catalyst carbon deposition and sintering. Also, TiO2 addition is conducive to the catalyst regeneration process by reducing the activation energy of oxidative decarburization. Hydrogen yield was efficiently promoted by the synthesized catalyst. Consequently, under the equivalent hydrogen (160 ml/min) produced over the catalyst, the SOFCs, with a cathode area of 15 cm2, display impressive performance (maximum power density, 404 mW/cm2) and excellent stability. Through cost-benefit analysis, the application of the synthesized catalyst is considered for great advantages in capital and energy saving. Ultimately, this work might offer a novel point of view for developing a low-cost, robust and efficient catalyst towards indirect hydrogen production for SOFCs.

Bimetallic Fe-Mo sulfide/carbon nanocomposites derived from phosphomolybdic acid encapsulated MOF for efficient hydrogen generation

To tackle the energy crisis and achieve more sustainable development, hydrogen as a clean and renewable energy resource has attracted great interest. Searching for cheap but efficient catalysts for hydrogen production from water splitting is urgently needed. In this report, bimetallic Fe-Mo sulfide/carbon nanocomposites that derived from a polyoxometalate phosphomolybdic acid encapsulated metal-organic framework MIL-100 (PMA@MIL-100) have been generated and their applications in electrocatalytic hydrogen generation were explored. The PMA@MIL-100 precursor is formed via a simple one-pot hydrothermal synthesis method and the bimetallic Fe-Mo sulfide/carbon nanocomposites were obtained by chemical vapor sulfurization of PMA@MIL-100 at high temperatures. The nanocomposite samples were fully characterized by a series of techniques including X-ray diffraction, Fourier-transform infrared analysis, thermogravimetric analysis, N2 gas sorption, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and were further investigated as electrocatalysts for hydrogen production from water splitting. The hydrogen production activity of the best performed bimetallic Fe-Mo sulfide/carbon nanocomposite exhibits an overpotential of -0.321 V at 10 mA cm−2 and a Tafel slope of 62 mV dec-1 with a 53 % reduction in overpotential compared to Mo-free counterpart composite. This dramatic improvement in catalytic performance of the Fe-Mo sulfide/carbon composite is attributed to the homogeneous distribution of the nanosized iron sulfide, MoS2 particles, and the formation of Fe-Mo-S phases in the S-doped porous carbon matrix. This work has demonstrated a potential approach to fabricate complex heterogeneous catalytic materials for different applications.

Hierarchically Ordinated Two-Dimensional MoS2 Nanosheets on Three-Dimensional Reduced Graphene Oxide Aerogels as Highly Active and Stable Catalysts for Hydrogen Evolution Reaction

Hydrogen gas (H2) is being intensively proposed as a next-generation clean energy owing to the depletion of fossil fuels. Electrochemical water splitting is one of the most promising processes for hydrogen production. Furthermore, many efforts focusing on electrochemical water splitting have been made to develop low-cost, electrochemically active, and stable catalysts for efficient hydrogen production. MoS2 has emerged as an attractive material for developing catalysts for the hydrogen evolution reaction (HER). Hence, in this study, we design hierarchically ordinated two-dimensional (2D) MoS2 nanosheets on three-dimensional (3D) reduced graphene oxide (rGO) (H-2D/3D-MoS2-rGO) aerogel structures as a new class of electrocatalysts for the HER. We use the one-pot hydrothermal synthesis route for developing high-performance electroactive materials for the HER. The as-prepared H-2D/3D-MoS2-rGO contains a unique 3D hierarchical structure providing large surface areas owing to the 3D porous networks of rGO and more active sites owing to the many edge sites in the MoS2 nanosheets. In addition, the H-2D/3D-MoS2-rGO structure exhibits remarkable electrochemical properties during the HER. It shows a lower overpotential than pure MoS2 and excellent electrochemical stability owing to the large number of active sites (highly exposed edge sites) and high electrical conductivity from the rGO structure.

Porous nickel powder supported Ni–P/CNTs: an efficient catalyst for hydrogen production via water splitting

It is of great significance to develop and prepare a kind of earth-abundant and a low-cost non-noble metal catalyst to replace the noble metal catalyst for the hydrogen evolution reaction (HER). Transition metal phosphides (TMP) has great potential for alleviating the energy crisis in catalytic applications. Herein, we report the synthesis of nickel phosphides decorated on carbon nanotubes (Ni–P/CNTs) using a porous nickel powder by a simple, traditional and effective method of powder metallurgy. The Ni–P/CNTs catalyst obtained at 700 °C for 60 min performs a better catalytic activity than samples prepared under other process conditions in acidic solutions during our experiment. This catalytic activity may be associated with the flower-shaped morphology, electrochemically active surface areas and contents of P of hybrid catalyst. This work will provide a promising pathway for designing various transition metal compounds and exploring the performance in catalysts for energy-related catalysis processes using porous metal materials.

Nanocrystalline cobalt–nickel–boron (metal boride) catalysts for efficient hydrogen production from the hydrolysis of sodium borohydride

Innovative metal boride nanocatalysts containing crystalline Co–Ni based binary/ternary boride phases were synthesized and used in the hydrolysis of NaBH4. All the as-prepared catalysts were in high-purity with average particle sizes ranging between ~51 and 94 nm and consisting of different crystalline phases (e.g. CoB, Co2B, Co5B16, NiB, Ni4B3, Ni2Co0·67B0.33). The synergetic effect of the different binary/ternary boride phases in the composite catalysts had a positive role on the catalytic performances thus, while the binary boride containing phases of unstable cobalt borides or single Ni4B3 were not showing any catalytic activity. The Co–Ni–B based catalyst containing crystalline phases of CoB–Ni4B3 exhibited the highest H2 production rate (500.0 mL H2 min−1 gcat−1), with an apparent activation energy of 32.7 kJ/mol. The recyclability evaluations showed that the catalyst provides stability even after the 5th cycle. The results suggested that the composite structures demonstrate favorable catalytic properties compared to those of their single components and they can be used as alternative and stable catalysts for efficient hydrogen production from sodium borohydride.

Flower-like nanosheets directly grown on Co foil as efficient bifunctional catalysts for overall water splitting

Hydrogen generation through electrochemical water decomposition is a promising method to address the global energy crisis. Herein, we report the synthesis of a series of flower-like Mo3S4/Co1-xS composites on Co foil (Mo3S4/Co1-xS@CF) as high-performance electrochemical water-splitting catalysts in an alkaline environment. The flower-like array structure of Mo3S4/Co1-xS@CF not only increases the electrochemically active surface area of ​​the catalyst, but also facilitates the release of bubbles generated, resulting in enhanced catalytic activity. For the hydrogen evolution reaction, the Mo3S4/Co1-xS@CF electrode exhibits good stability and excellent catalytic activity in 1.0 M KOH (η10 = 105 mV), 1.0 M PBS (η10 = 92 mV) and 0.5 M H2SO4 (η10 = 68 mV) solutions. For the oxygen evolution reaction, the electrode displays excellent stability and catalytic activity in 1.0 M KOH solution (η10 = 215 mV). When used for overall water splitting in 1.0 M KOH solution, Mo3S4/Co1-xS@CF achieves a current density of 10 mA cm−2 at a low potential of 1.58 V and maintains it stably for 40 h. This study presents a simple method for preparing transition metal-based bimetallic composite catalysts for efficient hydrogen production.

Functionalized biochars as supports for Pd/C catalysts for efficient hydrogen production from formic acid

Biomass waste product was used to generate biochars as catalytic supports for selective hydrogen production from formic acid. The supports were obtained after pyrolysis in CO2 atmosphere of non-pretreated and chemically ZnCl2 activated raw materials (vine shoot and crystalline cellulose). The support series includes materials with different textural properties and surface chemistry. The support nature and especially textural properties firstly affects significantly Pd size and dispersion and its interaction with the support and secondly influence in a great extent the catalytic behavior of the final material. The presence of prevailing mesoporous character appeared to be the most important parameter influencing formic acid dehydrogenation and overall hydrogen production.

Iron doped nanocomposites based efficient catalyst for hydrogen production and reduction of organic pollutant

Iron doped nanocomposites based effective material were prepared for catalytic reduction of an organic pollutant and hydrogen production. Electrochemical production of hydrogen based on water splitting has been deliberated as an auspicious approach, however, the lethargic anodic oxygen evolution reaction (OER) restricts the effectiveness of water splitting. Also, active catalysts for catalytic reduction of organic pollutants are also highly required for the catalytic removal of organic pollutants. Therefore, in this manuscript, we report iron doped metal oxide nanocomposites (Fe2O3-ZnO and Fe-SnO2) as multifunctional catalysts for OER, hydrogen evolution reaction (HER) as well as catalytic reduction of organic pollutants. Therefore, efficient nano-catalyst based on iron oxide doped tin oxides and iron doped zinc oxide with long-term stability and efficient hydrogen generation and removal of organic pollutants has been developed. The catalytic efficiency of the developed materials was evaluated toward producing hydrogen and removing organic pollutants. In HER, it was found that Fe2O3-ZnO and Fe-SnO2 needs a low over potential to produce 10 mA cm−2 in 0.5 M KOH and 0.5 M H2SO4. Similarly, in OER, 600 mV is needed to drive the current density of 20 mA cm−2 in 1.0 M KOH using Fe2O3-ZnO. Fe2O3-ZnO illustrates lower Tafel slopes of 64.3 mV dec-1 and 96.0 mV dec-1 in HER using 0.5 M KOH and 0.5 M H2SO4, respectively, while in OER, the Tafel slope is 76.5 mV dec-1 using 1.0 M KOH. The catalytic efficiency of Fe2O3-ZnO and Fe-SnO2 was also evaluated for the removal of 4-nitrophenol and among them, Fe-SnO2 displayed good catalytic efficiency toward 4-nitrophenol reduction. 4-Nitrophenol was totally reduced in less than 5 min using Fe-SnO2 as a catalyst.