Cobalt nanoparticles supported on magnetic core-shell structured carbon as a highly efficient catalyst for hydrogen generation from NaBH4 hydrolysis

A novel recyclable cobalt nanocatalyst, supported on magnetic carbon with core-shell structure, was successfully synthesized by using wetness impregnation-chemical reduction method for hydrogen generation from hydrolysis of NaBH₄. The resultant nanocomposite was characterized to determine the structural and physical-chemical properties by a series of analytical techniques such as FT-IR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction), SEM (scanning electron microscope), EDX (energy-dispersive X-ray spectroscopy), TEM (transmission electron microscopy), etc. The results demonstrated that amorphous cobalt nanoparticles were homogeneously surrounded on the surface of the support due to having abundant hydrophilic groups (such as aldehyde and hydroxyl groups) on the surface of carbon layer for the effective immobilization of metal ions. The supported catalyst showed superior catalytic performance towards the hydrolysis reaction of NaBH₄ at room temperature. The total rate of hydrogen generation and activation energy were calculated to be 1403 ml H₂ g_cat^?1 min^?1 and 49.2 kJ mol^?1, respectively, which were comparable to the values of most cobalt-based catalyst reported for hydrogen production from hydrolysis of NaBH₄. Additionally, reusability test revealed that the hydrogen in NaBH₄ substrate could be completely released within 25 min with a minimum hydrogen generation rate of 832 ml H₂ g_cat^?1 min^?1 even after five runs of hydrolytic reaction, implying the as-prepared Co/Fe₃O₄@C composite could be considered as a promising candidate catalyst for portable hydrogen fuel system such as PEMFC (proton exchange membrane fuel cells).     

Bacterial cellulose derived carbon as a support for catalytically active Co–B alloy for hydrolysis of sodium borohydride

The fast release of hydrogen from borohydride is highly desired for a fuel cell system. However, the generation of hydrogen from borohydride is limited by the low activity and low stability of the catalyst. Herein, a highly active catalyst is synthesized through a simple one-step chemical reduction using bacterial cellulose (BC) derived carbon as a support for the active Co–B alloy. The morphology and microstructure of the BC/Co–B nanocomposite are characterized by SEM, TEM, XRD, and BET adsorption analysis. The BC/Co–B possesses high surface area (125.31 m² g^?1) high stability and excellent catalytic activity for the hydrolysis of NaBH₄. Compared with unsupported Co–B nanocomposite or commercial carbon supported Co–B, the BC/Co–B nanocomposite shows greatly improved catalytic activity for the hydrolysis of NaBH₄ with a high hydrogen generation rate of 3887.1 mL min^?1 g^?1 at 30 °C. An activation energy of 56.37 kJ mol^?1 was achieved for the hydrolysis reaction. Furthermore, the BC/Co–B demonstrated excellent stability. These results indicate that the BC/Co–B nanocomposite is a promising candidate for the hydrolysis of borohydrides.     

Synthesis of Ni/TiO2 catalyst by sol-gel method for hydrogen production from sodium borohydride

Hydrogen is a sustainable, renewable and clean energy carrier that meets the increasing energy demand. Pure hydrogen is produced by the hydrolysis of sodium borohydride (NaBH₄) using a catalyst. In this study, Ni/TiO₂ catalysts were synthesized by the sol-gel technique and characterized by X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) methods. The effects of Ni loading ratio (20–40%), catalyst amount (75–200 mg), the concentration of sodium hydroxide (NaOH, 0.25–1 M), initial amount of NaBH₄ (75–125 mg) and the reaction temperature (20–60 °C) on hydrogen production performance were examined. The hydrogen yield (100%) and hydrogen production rate (110.87 mL/g_cat.min) were determined at the reaction conditions of 5 mL of 0.25 M NaOH, 100 mg NaBH₄, 100 mg Ni/TiO₂, 60 °C. Reaction order and activation energy were calculated as 0.08 and 25.11 kJ/mol, respectively.     

Fabrication and characterization of poly(tannic acid) coated magnetic clay decorated with cobalt nanoparticles for NaBH4 hydrolysis: RSM-CCD based modeling and optimization

Hydrogen generation from sodium borohydride (NaBH₄) hydrolysis in the presence of metal catalysts is a frequently used and encouraging method for hydrogen storage. Metal nanoparticle-supported catalysts are better recyclability and dispersion than unsupported metal catalysts. In this study, the synthesis and characterization of a polymer-supported catalyst for hydrogen generation using NaBH₄ have been investigated. For the synthesis of polymeric material, first of all, kaolin (KLN) clay has been magnetically rendered by using the co-precipitation method (Fe₃O₄@KLN) and then coated with poly tannic acid (PTA@Fe₃O₄@KLN). Then, the catalyst loaded with cobalt (Co) nanoparticles have been obtained with the NaBH₄ reduction method (Co@PTA@Fe₃O₄@KLN). The surface morphology and structural properties of the prepared catalysts have been determined using methods such as scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma mass spectrometry (ICP-MS) and vibrating sample magnetometer (VSM). The optimization of the most important variables (NaBH₄ amount, NaOH amount, catalyst amount, and metal loading rate) affecting the hydrolysis of NaBH₄ using the synthesized polymeric catalysts was carried out using response surface methodology (RSM). Depending on the evaluated parameters, the desired response was determined to be hydrogen production rate (HGR, mL/g min). HGR was 1540.4 mL/g_cat. min. in the presence of the Co@PTA@Fe₃O₄@KLN at optimum points obtained via RSM (NaBH₄ amount 0.34 M, NaOH amount 7.9 wt%, catalyst amount 3.84 mg/mL, and Co loading rate 6.1%). The reusability performance of the catalyst used in hydrolysis of NaBH₄ was investigated under optimum conditions. It was concluded that the catalyst is quite stable.     

A study on hydrogen generation from NaBH4 solution using Co-loaded resin catalysts

Hydrogen production via chemical processes has gained great attention in recent years. In this study, Co-based complex catalyst obtained by adsorption of Co metal to Amberlite IRC-748 resin and Diaion CR11 were tested for hydrogen production from alkaline NaBH₄ via hydrolysis process. Their catalytic activity and microstructure were investigated. Process parameters affecting the catalytic activity, such as NaOH concentration, Co percentage and catalyst amount, as well as NaBH₄ concentration and temperature were investigated. Furthermore, characteristics of these catalysts were carried out via SEM, XRD and FT-IR analysis. Hydrogen production rates equal to 211 and 221 ml min⁻¹ g_cat⁻¹ could be obtained with Amberlite IRC-748 resin and Diaion CR11 Co based complex catalysts, respectively. The activation energies of the catalytic hydrolysis reaction of NaBH₄ were calculated as 46.9 and 59.42 kJ mol⁻¹ for Amberlite IRC-748 resin and Diaion CR11 based catalysts respectively kJ mol⁻¹ from the system consisting of 3% Co, 10 wt% NaBH₄ and 7 wt% NaOH as well as 50 mg catalyst dosage. It can be concluded that Co-based resins as catalysts for hydrogen production is an effective alternative to other catalysts having higher rate.     

Magnetic dendritic KCC-1 nanosphere-supported cobalt composite as a separable catalyst for hydrogen generation from NaBH4 hydrolysis

The introduction of magnetism into a catalyst can greatly optimize its separation performance. In the present work, a kind of magnetically separable catalysts for promoting NaBH₄ hydrolysis have been fabricated by anchoring cobalt nanoparticles on magnetic dendritic KCC-1 nanospheres composed of magnetic Fe₃O₄ core and fibrous shell. The fabricated catalysts were characterized with various characterization methods, including absorption spectroscopy (AAS), scanning electron microscopy (SEM), high-resolution transmission electronic microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometry (VSM), and Fourier transform infrared (FT-IR), etc. This kind of catalysts exhibit high catalytic activity for promoting the hydrolysis of NaBH₄ under alkaline conditions, giving a hydrogen generation rate and activation energy of 3.83 L min⁻¹ g_Co⁻¹ (30 °C) and 53.63 kJ mol⁻¹, respectively. After used for 5 cycles, the catalyst showed 36.5% catalytic activity reserved. Most importantly, the magnetism of the catalyst made it easily separated and recycled from the solution after the reaction completed. The development of this kind of catalysts could provide a promising option for catalyzing NaBH₄ hydrolysis for portable hydrogen production from.     

Polypyrrole supported Co–W–B nanoparticles as an efficient catalyst for improved hydrogen generation from hydrolysis of sodium borohydride

Effective and reusable catalysts with high performance are essentially necessary for NaBH₄ based on-demand hydrogen generators to the widespread use for energy conversion in fuel cell power systems. Herein, we report a facile synthesis of surfactant-directed polypyrrole-supported Co–W–B nanoparticles as a robust catalyst for efficient hydrolysis of NaBH₄ reaction. This non-noble metal catalyst provides much higher catalytic activity than a conventional cobalt boride catalyst. By incorporating tungsten to catalyst composition and tuning molar ratio of W/(Co + W), about a four-fold higher hydrogen generation rate was attained compared to bare Co–B. Among the all catalysts tested, Co–W–B/PPy with 7.5% W possessed the remarkable catalytic performance of 9.92 L min^?1 g^?1 and high stability over five cycles with the apparent activation energy of 49.18 kJ mol^?1.     

Stability and kinetic studies of MOF‐derived carbon‐confined ultrafine Co catalyst for sodium borohydride hydrolysis

A mesoporous carbon‐confined cobalt (Co@C) catalyst was fabricated by pyrolysis of macroscale Co‐metal–organic framework (MOF) crystals and used to catalyze NaBH₄ hydrolysis for hydrogen production. To reveal the structural changes of cobalt nanoparticles, we characterized the fresh and used Co@C catalysts using X‐ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and N₂ adsorption. This MOF‐derived Co@C exhibits high and stable activity toward NaBH₄ hydrolysis. No obvious agglomeration of Co nanoparticles occurred after five consecutive runs, implying good resistance of Co@C composite to metal aggregation. The kinetics of NaBH₄ hydrolysis was experimentally studied by changing initial NaBH₄ concentration, NaOH concentration, and catalyst dosage, respectively. It was found that the hydrogen generation rate follows a power law: r = A exp (?45.0/RT)[NaBH₄]^0.985[cat]^1.169[NaOH]^?0.451 .     

Effect of phosphoric acid addition on the hydrogen production from hydrolysis of NaBH4 with Cu based catalyst

Cu based catalysts were synthesized in water and methanol solvents by chemical reduction with sodium borohydride (NaBH₄). The obtained catalyst was used to catalyze the NaBH₄ hydrolysis reaction with phosphoric acid (H₃PO₄) including different concentrations. Surface morphology and structural properties of the Cu based catalysts prepared in water and methanol solvents were studied using by X-ray diffraction (XRD), scanning electron microscopy (SEM), surface area measurements and Fourier-transform infrared spectroscopy (FTIR) analyses, respectively. The catalytic activity of the catalysts has been tested by measuring the hydrogen production rate by the acidified hydrolysis of NaBH₄. The maximum hydrogen production rates in the hydrolysis reaction including 0.25 M H₃PO₄ using the Cu based catalyst prepared in water and methanol solvents were 825 and 660 ml g^?1min^?1, respectively. At the same time, the hydrogen production experiments were carried out from this hydrolysis reaction with only H₃PO₄ and NaBH₄ interactions without using Cu metal catalyst. The activation energy obtained based on the nth order reaction model was found to be 61.16 kJ mol^?1.     

Optimisation of sepiolite clay with phosphoric acid treatment as support material for CoB catalyst and application to produce hydrogen from the NaBH4 hydrolysis

Herein, the CoB catalyst supported on the sepiolite clay treated with phosphoric acid was utilized to produce hydrogen from the NaBH₄ hydrolysis. In order to analyse the performance of the phosphoric acid treated sepiolite clay supported-CoB catalyst, the NaBH₄ concentration effect, phosphoric acid concentration effect, phosphoric acid impregnation time effect, CoB catalyst percentage effect, and temperature effect were studied. In addition, XRD, XPS, SEM, TEM, BET, and FTIR analysis were performed for characterization of Co–B catalyst supported on the acid-treated sepiolite. The completion time of this hydrolysis reaction with Co–B (20%) catalyst supported on the sepiolite treated by 5 M phosphoric acid was approximately 80 min, whereas the completion time of this hydrolysis reaction with acid-free sepiolite-supported Co–B (20%) catalyst was approximately 260 min. There is a five-fold increase in the maximum production rate. The maximum hydrogen production rates of this hydrolysis reaction at 30 and 60 °C were found as 1486 and 5025 ml min⁻¹g⁻¹_catalyst, respectively. Activation energy was found as 21.4 kJ/mol. This result indicates that the acid treatment on sepiolite is quite successful. The re-usability of NaBH₄ hydrolysis reaction by CoB catalyst supported on sepiolite treated phosphoric acid for successive five cycles of NaBH₄ at 30 °C was investigated.     

Co−O−P composite nanocatalysts for hydrogen generation from the hydrolysis of alkaline sodium borohydride solution

In recent years, catalytic hydrolysis of sodium borohydride is considered to be a promising approach for hydrogen generation towards fuel cell devices, and highly efficient and noble-metal-free catalysts have attracted increasing attention. In our present work, Co₃O₄ nanocubes are synthesized by solvothermal method, and then vapor-phase phosphorization treatment is carried out for the preparation of novel Co−O−P composite nanocatalysts composed of multiple active centers including Co, CoO, and Co₂P. For catalyst characterization, field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD) and X-ray photoelectric spectroscopy (XPS) are conducted. Optimal conditions for catalyst preparation and application were investigated in detail. At room temperature (25 °C), maximum hydrogen generation rate (HGR) is measured to be 4.85 L min⁻¹ g⁻¹ using a 4 wt% NaBH₄ − 8 wt% NaOH solution, which is much higher than that of conventional catalysts with single component reported in literature. It is found that HGR remarkably increases with the increasing of reaction temperature, and apparent activation energy for catalytic hydrolysis of NaBH₄ is calculated to be 63 kJ mol⁻¹. After reusing for five times, the Co−O−P composite nanocatalysts still retains 78% of the initial activity.     

Phosphorus doped carbon nanodots particles based on pomegranate peels for highly active dehydrogenation of sodium borohydride in methanol

Here, the carbon nanodots were successfully synthesized from pomegranate peels (PPCD). This obtained PPCD was treated by a hydrothermal process with phosphoric acid for P doping (P doped PPCD) and used as a metal-free catalyst to obtain hydrogen(H₂) from sodium borohydride (NaBH₄) methanolysis for the first time. The characteristics of the samples obtained by ultraviolet, fluorescence, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM) and Inductively coupled plasma mass spectrometry (ICP-MS) analyses were examined. NaBH₄ concentration effect, temperature effect and catalyst reusability experiments were carried out. Using 10 mg of the catalyst with 2.5% NaBH₄, an HGR value of 13000 mL min^?1g^?1 was obtained. The activation energy (Ea) for the P-doped PPCD catalyst was 30.96 kJ mol^?1.     

Protection and confinement effect of carbon on Co/CoxOy nano-catalyst for efficient NaBH4 hydrolysis

The hydrolysis of sodium borohydride (NaBH₄) over catalysts is a promising method to produce hydrogen. Although Co-based catalysts exhibit high activity for NaBH₄ hydrolysis, they are still far from satisfying practical applications, especially their poor durability in alkaline media. Herein, a carbon shell structure was designed and synthesized to improve the stability of the mixture of Co⁰ and Co_xO_y nanofilms (Co/Co_xO_y@C) during NaBH₄ hydrolysis via a facile polymerization-pyrolysis strategy with Co/Co_xO_y nanofilms as the precursor. As a result, the Co/Co_xO_y@C catalyst can achieve a remarkable H₂ generation rate of 4348.6 mL min^?1 g_Co^?1 with a low activation energy of 43.6 kJ mol^?1, which is superior to most previously reported catalysts. Moreover, the catalyst shows high stability with an H₂ generation-specific rate of 79% after five cycles. The excellent performance of carbon substrate can well prevent the agglomeration of Co-based nanoparticle and improve the corrosion resistance of the active Co to BO₂^? and OH^?. This work would widen the road for the preparation of nanoconfined catalysts, which has prospective application potentials for H₂ production from NaBH₄ hydrolysis.     

Co complex modified on Eupergit C as a highly active catalyst for enhanced hydrogen production

In present paper, the preparation and catalytic activity of Eupergit C polymer (EC) modified Co complex was reported. Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Brunauer-Emmett-Teller Surface Area Analysis (BET), Fourier Transform Infrared Spectroscopy (FT-IR), Transmission Electron Microscopy (TEM) coupled with energy dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS) were used to characterization of catalyst. EC modified-Co complex was the first time examined as a catalyst in NaBH₄ hydrolysis to H₂ evolution. The kinetic calculations were determined by using two different kinetic methods. The low activation energy barriers were achieved as 21.673 kJ mol^?1 for nth order model and as 21.061kJmol^?1 for Langmuir-Hinshelwood (L-H) model at low temperatures. EC modified-Co complex catalyst exhibited high performance with H₂ evolution rates of 3914 mL H₂g_cat^?1min^?1 and 9183 mLH₂g_cat^?1min^?1 at 30 °C–50 °C. Additionally, Langmuir–Hinshelwood mechanism was explained for EC modified Co complex catalyzed sodium borohydride hydrolysis reaction. The reusability experiments showed that EC modified-Co complex catalyst maintained excellent stability with 100% conversion and without significant lost after the 6th run.     

g-C3N4 particles with boron and oxygen dopants/carbon vacancies for efficient dehydrogenation in sodium borohydride methanolysis

In the study, metal-free boron and oxygen incorporated graphitic carbon nitride (B and O doped g-C₃N₄) with carbon vacancy was successfully prepared and applied as a catalyst to the dehydrogenation of sodium borohydride (NaBH₄) in methanol for the first time. The hydrogen generation rate (HGR) value was found to be 11,600 mL min^?1g^?1 by NaBH₄ of 2.5%. This is 2.53 times higher than the g-C₃N₄ catalyst without the addition of B and O. The obtained activation energy was 25.46 kJ mol^?1. X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM), energy dispersive X-Ray analyser (EDX), Transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR) analyses for characterization were performed. A possible mechanism of H₂ production from the reaction using metal-free B and O doped g-C₃N₄ catalyst with carbon vacancy has been proposed. This study showed that g-C₃N₄ and its composites with doping atoms can be used effectively in H₂ production by NaBH₄ methanolysis.     

Highly active porous Co–B nanoalloy synthesized on liquid-gas interface for hydrolysis of sodium borohydride

Porous Co–B nanoalloy is a low-cost and highly active catalyst towards the hydrolysis of sodium borohydride (NaBH₄). In this study, a facile and room-temperature hydrogen bubble-assisted method was developed to prepare porous Co–B nanoalloy (Co-B_bubble) materials exhibiting high catalytic activity. The obtained materials are characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive spectroscopy, X-ray photoelectron spectroscopy, inductively coupled plasma-optical emission spectrometer, transmission electron microscopy and surface area experiments. It is found that the hydrogen bubbles generated in-situ in the reaction system can act as template, which played an important role in determining the porous architecture of the final Co–B product. In the hydrolysis of sodium borohydride for hydrogen generation, the porous Co-B_bubble nanoalloy materials exhibit high catalytic activity with mass normalized rate constant of 5.31 L_hydrogen min^?1 g_catalyst^?1; a value which is much higher than those obtained for many other Co–B catalysts recently reported in the literature. The apparent activation energy (Ea) of the catalytic process is found to be ca. 30 kJ mol^?1. It is proposed that the high catalytic performance and low cost of Co-B_bubble nanoalloy catalyst can be a promising material candidate in the hydrolysis of sodium borohydride for hydrogen production for commercial applications.     

Chitosan-mediated Co–Ce–B nanoparticles for catalyzing the hydrolysis of sodium borohydride

Highly dispersed Co–Ce–B nanoparticles supported on chitosan-derived carbon (Co–Ce–B/Chi–C) were synthesized through chemical reduction and carbonization. The morphology and microstructure of the Co–Ce–B/Chi–C nanocomposite were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and Brunauer–Emmett–Teller adsorption analysis. This nanocomposite had uniform morphology and large surface area, and it showed high catalytic activity for NaBH₄ hydrolysis and good cycle stability. Compared with unsupported Co–Ce–B particles, this nanocomposite showed greatly increased catalytic activity for NaBH₄ hydrolysis. A remarkably high hydrogen generation rate of 4760 mL^?1 min^?1 g^?1 at 30 °C was achieved with low activation energy of 33.1 kJ mol^?1. These results indicate that the Co–Ce–B/Chi–C nanocomposite is a promising catalyst for on-demand hydrogen generation via NaBH₄ hydrolysis.     

Effects of blast furnace slag (BFS) and cobalt-boron (Co-B) on hydrogen production from sodium boron hydride

In the present paper, the blast furnace slag (BFS) supported Co-B catalyst were investigated in detail. The impregnation-chemical reduction method was used while hydrochloric (HCl) acid treated BFS samples (BFS⁺) were prepared. Catalyst samples were analyzed in three main groups as base BFS (BFS⁰), BFS⁰-Co-B and BFS⁺-Co-B. The effects of these catalyst samples on hydrogen production from the solid-state sodium boron hydride (NaBH₄) are analyzed in this study. The effects of some parameters such as the ingredients of blast furnace slag, the molarity of hydrochloric acid treatment, the Co percentages and the solution temperatures were investigated on the hydrolysis performance of NaBH₄. The NaBH₄ hydrolysis reaction with the BFS⁰ is treated by the BFS⁺-Co-B-20% catalyst was completed approximately 25 min and the hydrolysis reaction with the BFS⁰-Co-B-20% catalyst was completed approximately 20 min whereas the hydrolysis reaction of NaBH₄ was completed in 1 h 35 min. The hydrogen production rates at pre-heated to max 40, 50 and 60 °C were measured as 55.12, 64.47 and 70.41 L/min.g_catalyst, respectively. According to another result of the study, the high-efficiency solid-state BFS-Co-B & NaBH₄ mixtures were covered with the PVA (Polyvinyl alcohol) film to make them more resistant to environmental effects such as humidity.     

Metal-free catalyst fabrication by incorporating oxygen groups on the surface of the carbonaceous sample and efficient hydrogen production from NaBH4 methanolysis

In the present study, metal-free catalysts for efficient H₂ generation from NaBH₄ methanolysis was produced for the first time from apricot kernel shells with two-step activation. The first stage of the two-stage activation includes the production of activated carbon with the KOH agent (AKOH), and the second stage includes hydrothermally HNO₃ activation with oxygen doping (O doped AKOH + N). The hydrogen production rate (HGR) and the activation energy (Ea) of the reaction with the obtained metal-free catalyst (10 mg) were determined as 14,444 ml min^?1 g^?1 and 7.86 kJ mol^?1, respectively. The structural and physical-chemical properties of these catalysts were characterized by XRD (X-ray diffraction), SEM (scanning electron microscopy), elemental CHNS analysis, FT-IR (Fourier transform infrared spectroscopy), and nitrogen adsorption analysis. Also, the reusability results of this metal-free catalyst for H₂ production are promising.     

Preparation of CoB/ZIF-8 supported catalyst by single step reduction and its activity in hydrogen production

CoB/ZIF-8 supported catalysts were successfully prepared using Co/Zn-ZIF-8 as the precursor by single-step reduction, which was applied in hydrogen release from the hydrolysis of NaBH₄. Reducible Co ions of Co/Zn-ZIF-8 can be partially in-situ transformed into CoB by direct reduction, whereas ZIF-8 framework structure can be well preserved due to the resistance of Zn to reducing ambiences. Accordingly, CoB active components can be highly loaded onto ZIF-8 support to produce CoB/ZIF-8 catalysts. The texture evolution of Co/Zn-ZIF-8 during reduction was investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscope and nitrogen adsorption–desorption isotherms. Compared with the reduction of Co-ZIF-67, the framework structure of Co/Zn-ZIF-8 can be effectively preserved although Co ions of Co/Zn-ZIF-8 were partially reduced into cobalt-based alloy. In the hydrogen release from hydrolysis of NaBH₄, CoB/ZIF-8 supported catalyst exhibits excellent catalytic activity. The effect of NaOH concentration, NaBH₄ concentration and reaction temperature on hydrolysis reaction of NaBH₄ was deeply studied based on this catalyst. Compared with other published catalysts, this catalyst exhibits relatively low activation energy of about 57.72 kJ mol^?1.