Shaggy-like Ru-clusters decorated core-shell metal-organic framework-derived CoOx@NPC as high-efficiency catalyst for NaBH4 hydrolysis

Achieving high catalytic performance with the lowest possible amount of noble metal is critical for any catalytic applications. Herein, we report a controllable method of preparing low Ru loaded, N-doped porous carbon embedded with cobalt oxide species (Ru/CoO_x@NPC) using core-shell metal-organic framework (MOF) as a template. The optimized catalyst exhibits a highly powerful yet stable performance of H₂ production through sodium borohydride (NaBH₄) hydrolysis. The Ru/CoO_x@NPC catalyst shows a fast H₂ generation rate (8019.5 mL min^?1 g_cat^?1), high turnover frequency (1118.6 mol min^?1 mol_Ru^?1), and reusability. The carbonized ZIF-8 core and the ZIF-67 outer shell supplies a porous carbon moiety that not only improves the conductivity and but also provides uniform distribution of the active sites. The XPS analysis indicates that there is a strong electronic interaction between Co species and Ru species. The superior catalytic performance can be attributable to the large specific surface area as well as the synergy between Co-oxide and Ru clusters.     

A comparative study on the catalytic activities and stabilities of atomic-layered platinum on dispersed Ti0.9Cu0.1N nanoparticles supported by N-doped carbon nanotubes (N-CNTs) and reduced graphene oxide (N-rGO)

In our previous research, titanium-based nitride with high conductivity and superior corrosion resistance were developed as an ideal core material for replacing noble metal to form Pt-based core-shell catalysts by pulse electrodeposition. Meanwhile, the smaller sizes of nitride cores would also be available for pulse electrodeposition by dispersing them on carbon nanotubes (CNT). To achieve a better practice on the preparation of the Pt-based core-shell catalysts, in this work, both nitrogen-doped carbon nanotubes (N-CNT) and reduced graphene oxide (N-rGO) were used to support the copper-doped titanium nitride (Ti_0.9Cu_0.1N) cores. In the course of pulse electrodeposition, their influences as supports on the electronic states of electrodeposited Pt as well as their catalytic activities were compared. The results showed that the Pt preferred to electrodeposit on Ti_0.9Cu_0.1N cores supported by N-CNT and formed a core-shell structure. While with the same electrodeposition process, the Pt was found to be electrodeposited not only on the Ti_0.9Cu_0.1N cores supported by N-rGO with heavy aggregations but also on the N-rGO support. Raman spectroscopy analysis indicated that the higher degree of structural defects on N-rGO, as support, might have contributed to such divergence observation.     

Preparation of carbon nanotube and graphene doped polyphenylene sulfide flexible film electrodes and the electrodeposition of Cu2O nanocrystals for hydrogen-generation

Through annealing and electrochemical reduction methods, we successfully fabricates reduced graphene oxide layer (RGOL) modified carbon nanotube and reduced graphene oxide (CNT + RGO) doped polyphenylene sulfide (PPS) flexible thin film electrodes. These composite structure films can not only overcome the brittle nature of PPS, but also make good use of the thermal stability of PPS. Furthermore, carbon nanotube and reduced graphene oxide enhance the electrical conductivity of the composite films. Truncated octahedral and cuboctahedral Cu₂O nanocrystals are synthesized on RGOL modified CNT + RGO doped PPS (RGOL@PPS/CNT + RGO) composite film by a facile electrodeposition method without using any surfactants or external heating. RGOL on the PPS/CNT + RGO substrate facilitates the formation of Cu₂O morphology. The obtained Cu₂O composite film shows a superior ability for the hydrogen evolution reaction (HER) compared with other Cu₂O electrocatalysts. The Cu₂O with a smaller loading less than 0.04 mg cm^?2 on the composite film exhibits excellent HER activities with a low onset potential of 0.05 V and large current densities. The results of the HER performance indicates that the RGOL@PPS/CNT + RGO composite film has a potential application in flexible hydrogen-producing devices.     

Rational design of hierarchical core-shell structured CoMoO4@CoS composites on reduced graphene oxide for supercapacitors with enhanced electrochemical performance

Engineering multicomponent active materials as an advanced electrode with the rational designed core-shell structure is an effective way to enhance the electrochemical performances for supercapacitors. Herein, three-dimensional self-supported hierarchical CoMoO₄@CoS core-shell heterostructures supported on reduced graphene oxide/Ni foam have been rationally designed and prepared via a facile approach. The unique structure and the synergistic effects between two different materials, as well as excellent electronic conductivity of the reduced graphene oxide, contribute to the increased electrochemically active site and enhanced capacitance. The core-shell CoMoO₄@CoS composite displays the superior specific capacitance of 3380.3 F g⁻¹ (1 A g⁻¹) in the three-electrode system and 81.1% retention of the initial capacitance even after 6000 cycles. Moreover, an asymmetric device was successfully prepared using CoMoO₄@CoS and activated carbon as positive/negative electrodes. It is worth mentioning that the device delivered the high energy density of 59.2 W h kg⁻¹ at the power density of 799.8 W kg⁻¹ and the excellent cycle performance (about 91.5% capacitance retention over 6000 cycles). These results indicate that the core-shell CoMoO₄@CoS composites offers the novelty strategy for preparation of electrodes for energy conversion and storage devices.     

Fabrication of robust CoP/Ni2P/CC composite for efficient hydrogen evolution reaction and the reduction of graphene oxide

Developing the novel catalysts with an excellent performance of hydrogen generation is essential to facilitate the application of hydrogen evolution reaction (HER). Herein, a heterostructured cobalt phosphide/nickel phosphide/carbon cloth (CoP/Ni₂P/CC) composite was fabricated via an interfacial engineering strategy to achieve the modification of CoP nanoleaf on Ni₂P nanosheet skeleton supported by carbon cloth. By virtue of the unique heterostructure, abundant exposing active sites and the synergistic coupling effect of CoP and Ni₂P nanoparticles, the elaborated CoP/Ni₂P/CC composite exhibits a robust catalytic property. Among fabricated composites, the optimal CoP/Ni₂P/CC-4 catalyst behaves an excellent HER performance at a wide pH range (overpotentials of 67, 71 and 95 mV to afford 10 mA cm^?2 in 0.5 M H₂SO₄, 1 M KOH and 1 M PBS, respectively). The HER current density of this composite shows a negligible degradation after continuous test for 24 h. Charmingly, the HER process of this catalyst was innovatively applied to reduce graphene oxide, and thus exploiting the fabrication route of reduced graphene oxide (rGO). We are sure that this work will provide a firm guideline for the exploitation of pH-universal HER catalysts and the exploration of HER application.     

Pronounced effect of phosphidization on the performance of CoOx encapsulated N-doped carbon nanotubes towards oxygen evolution reaction

Research on water splitting reaction is on priority to explore an alternative source of energy with little to no carbon emissions. Among the two half reactions of electrochemical water splitting, oxygen evolution reaction (OER) is highly desirable yet challenging to prepare a cost effective and viable electrocatalyst to boost the OER activity. Herein, we have prepared a novel electrocatalyst, CoO_x-CoP/N-CNTs, by the phosphidization of cobalt oxides (CoO_x) encapsulated N- doped carbon nanotubes (CoO_x/N-CNTs). The CoO_x/N-CNTs composite is derived via pyrolysis of cobalt based zeolitic imidazole framework (ZIF-12) at 950 °C under argon atmosphere. The CoO_x/N-CNTs is phosphidized at various temperatures ranging from 320 °C to 400 °C. The optimized temperature to attain the best catalytic activity is 380 °C. The phosphatized material, CoO_x-CoP/N-CNTs, shows superior performance towards OER with an overpotential of 250 mV @ 20 mAcm^?2 vs 532 mV @ 20 mAcm^?2 of un-phosphidized material, CoO_x/N-CNTs, which shows significant effect of phosphidization. The maximum current density of 160 mAcm^?2 in 1 M KOH solution is achieved.     

Phytic acid-derived Co2-xNixP2O7-C/RGO and its superior OER electrocatalytic performance

A phytic acid-derived Co_2-xNi_xP₂O₇-C/RGO composite was designed and facilely synthesized, in which phytic acid acted as both a phosphoric source and carbon source. Both carbon derived from phytic acid and reduced graphene oxide (RGO) in composite, enhanced the conductivity and thus improve its electrocatalytical capability. As-synthesized Co_1.22Ni_0.78P₂O₇-C/RGO composite exhibited excellent oxygen evolution reaction (OER) catalytic performances: At the current density of 10 mA cm⁻², only a low overpotential of 283 mV and a small Tafel slope of 51 mV dec⁻¹ were observed. Good OER catalytic performance was retained even after 10 h continuously running at a constant voltage, which is even comparable to those of first-rate noble metal catalyst RuO₂. In addition, the performances of Co_2-xNi_xP₂O₇-C/RGO catalysts were also strongly dependent on Ni content.     

Methanol to hydrogen conversion on cobalt–ceria catalysts prepared by magnetron sputtering

Methanol oxidation catalyzed by bi-layered or mixed oxides of cobalt and cerium was studied at atmospheric pressure by temperature-programmed reaction technique. The catalysts were deposited in the form of thin films by magnetron sputtering from Co and CeO₂ targets, forming double layer structures of CeO₂/CoO_x or CoO_x/CeO₂. Reaction selectivity and hydrogen production rates were monitored at O₂:CH₃OH reactant stoichiometries varied in the range 4:1–1:4, spanning from oxygen rich to oxygen lean reaction conditions. A complementary information in regard to thermal stability of the catalytic layers was obtained by X-ray photoelectron spectroscopy. A strong synergistic interaction between cerium and cobalt within the mixed oxide (driving dynamics of the Co²⁺/Co³⁺ and Ce⁴⁺/Ce³⁺ redox pairs and oxygen exchange) leads to a bi-functional catalyst. Particularly the CeO₂/CoO_x configuration proved to be significantly more active than the CoO_x alone and more stable, especially under reducing environments. Further optimization of reactivity can be provided via control of the adlayer coverage.     

CeO2 nanowires stretch-embedded in reduced graphite oxide nanocomposite support for Pt nanoparticles as potential electrocatalyst for methanol oxidation reaction

A novel hybrid composite RGO-CeO_{2 NWS} with the nanowire-sheet structure was synthesized by a facile hydrothermal process using ethanol/water as the solvent without any organic additives. The graphene oxide proceeds to reduce to graphene and chemical bonds form between graphene oxide and CeO_{2 NWS}. Pt-based catalysts with the RGO-CeO_{2 NWS} composite as the support were then prepared by a microwave-assisted polyol process. The resultant catalysts were characterized by X-ray diffraction, Raman spectroscopy, Scanning tunneling microscopy, X-ray photoelectron spectroscopy, High resolution transmission electron microscopy and electrochemical tests. The results show that the hybrid Pt/RGO₄-CeO_{2 NWS} exhibits the best catalytic activity and the increased catalytic efficiency of Pt in the hybrid catalysts is evidence that CeO_{2 NWS} are anchored onto the chemical defects in the wrinkles and edges of the graphene surface. This avoids the restacking of graphene oxide, thus hindering the Pt nanoparticles embedded in folding and increasing the exposed active sites. The changed valence state from Ce⁴⁺ to Ce³⁺ in CeO_{2 NWS} will introduce oxygen vacancies and thus promote the tolerance of intermediate species in methanol oxidation.     

Effect of Fe,Ni and Zn dopants in La0·9Sr0·1CoO3 on the electrochemical performance of single-component solid oxide fuel cell

Fe-, Ni- and Zn- doped La_0·9Sr_0·1CoO₃ are prepared and a single-component solid oxide fuel cell composed of 30 wt% perovskite oxide and 70 wt% samarium-doped ceria (SDC)-(Li_0·67Na_0.33)₂CO₃ is fabricated and characterized. When doping with either Fe, Ni or Zn, most cations occupy the Co³⁺ sites. X-ray photoelectron spectroscopy and oxygen temperature-programmed desorption characterizations show that Zn-doped La_0·9Sr_0·1CoO₃ exhibits notably high surface oxygen, causing higher catalytic activity for oxygen reduction reaction (ORR) than that of nondoped La_0·9Sr_0·1CoO₃. Fe or Ni doping into La_0·9Sr_0·1CoO₃ decreases surface oxygen, resulting in a lower catalytic activity toward ORR than La_0·9Sr_0·1CoO₃. Furthermore, X-ray diffraction, temperature-programmed reduction and transmission electron microscopy characterizations prove that after reduction, Fe-doped La_0·9Sr_0·1CoO₃ is reduced to Co_0·72Fe_0.28 alloy-oxide core-shell nanoparticles, resulting in a high catalytic activity for hydrogen oxygen reaction (HOR). However, NiCo₂O₄ are formed during the reduction of Ni-doped La_0·9Sr_0·1CoO₃, exhibiting a low catalytic activity for the HOR. Similarly, the low catalytic activity of reduced Zn-doped La_0·9Sr_0·1CoO₃ for the HOR is caused by the formation of ZnCo₂O₄. A single component fuel cell composed with Fe-doped La_0·9Sr_0·1CoO₃-SDC-(Li_0·67Na_0.33)₂CO₃ exhibits the highest P_max of 239.1 mW cm⁻² at 700 °C with H₂ as fuel, indicating that HOR processes are rate-determining steps.     

CoxMo(1−x)S2 intermixed reduced graphene oxide as efficient counter electrode materials for high-performance dye-sensitized solar cells

In this study, nanocomposite electrocatalysts composed of cobalt molybdenum sulfide flower-like nanosheets intermixed with reduced graphene oxide (Co_xMo_(1?x)S₂/rGO) were prepared by a facile one-step hydrothermal method and were used to prepare counter electrodes (CE) of high-performance dye-sensitized solar cells (DSSCs). The structural and morphological analysis of the nanocomposites were carried out using field emission scanning electron microscopy, micro-Raman, and X-ray photoelectron spectroscopies, which revealed 2-dimensional petal-like nanosheets of the ternary metal sulfides intermixed with the reduced graphene oxide sheets. The DSSCs fabricated using Co_xMo_(1?x)S₂/rGO (CMS-2/rGO) as the counter electrode material exhibited power conversion efficiency (PCE) of 9.04%, which was found to be superior to the PCEs of DSSCs with CEs made of MoS₂/rGO (7.56%), Co_xMo_(1-x)S₂ (7.04–7.78%), and conventional Pt (8.72%). The electrochemical measurements showed that the excellent electrocatalytic activity of the Co_xMo_(1?x)S₂/rGO on I₃^- can be attributed to the expanded active sites, improved charge transfer across the CE, and reduced electrode/electrolyte interface resistance. The facile preparation approach and outstanding catalytic behavior of Co_xMo_(1?x)S₂/rGO indicate that the nanostructured Co_xMo_(1-x)S₂/rGO intermix would be a cost-effective material over the platinum used in the CE of DSSCs.     

Nanostructured manganese oxide on fullerene soot for water oxidation under neutral conditions

The sluggish kinetics of oxygen-evolution reaction (OER) through water-oxidation reaction results in high overpotentials for water splitting. Among different compounds, carbon-based material/Mn oxide composites were reported as OER catalysts. Fullerene soot (FS), which contains a mixture of fullerenes and carbon blacks, is low-cost compared to fullerenes and is commercially available. Herein, the Mn oxide/fullerene soot (MnO_x/FS) composite was investigated as an OER catalyst under neutral conditions. The composite was prepared through the reaction of KMnO₄ and FS as a facile, easy, and low-cost procedure. In this method, amorphous Mn oxide is formed directly on FS. The material was characterized by a number of methods. Then, the OER catalytic activity of MnO_x/FS was studied in a LiClO₄ solution (pH ≈ 6.3). Compared to pristine FS, the OER activity of MnO_x/FS is 2.5 times higher at 2.25 V vs. RHE. The Tafel slopes for OER are 450 and 240 mV per decade for FS and the reported composite, respectively.     

Noble metal-free cobalt oxide (CoOx) nanoparticles loaded on titanium dioxide/cadmium sulfide composite for enhanced photocatalytic hydrogen production from water

In this present paper, cobalt oxide (CoO_x) is studied as an effective cocatalyst in a photocatalytic hydrogen production system. CoO_x-loaded titanium dioxide/cadmium sulfide (TiO₂/CdS) semiconductor composites were prepared by a simple solvothermal method and characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS), and X-ray photoelectron spectroscopy (XPS). Photocatalytic hydrogen production was studied using the as-synthesized photocatalysts in aqueous solution containing sodium sulfide (Na₂S)/sodium sulfite (Na₂SO₃) as hole scavengers under visible light irradiation (λ > 400 nm). The optimal cobalt content in CoO_x-loaded TiO₂/CdS composite is determined to be 2.1 wt% and the corresponding rate of hydrogen evolution is 660 μmol g⁻¹ h⁻¹, which is about 7 times higher than TiO₂/CdS and CdS photocatalysts under the same condition. Visible light-driven photocurrents of the semiconductor composites were further measured on a photoelectrochemical electrode, revealing that the photocorrosion of CdS can be prevented due to the presence of TiO₂–CoO_x.     

Preparation and hydrogen penetration performance of TiO2/TiCx composite coatings

Titanium carbide is a good candidate for tritium permeation barrier in a fusion reactor. However, its oxidation susceptibility and the mismatch between the ceramic coating and substrate are still a challenge. In this study, a promising candidate as a hydrogen permeation barrier, comprising a titanium-based ceramic TiO₂/TiC_x composite coating, was proposed. The preparation process of this TiO₂/TiC_x composite coating involves two steps of carbon ion implantation and oxidation under ultra-low oxygen partial pressure. According to the results, the optimal oxidation temperature for TiO₂ coating is 550 °C, with the increase of the oxidation temperature, the particles on the surface of the oxide layer become coarse and loosely arranged, and the protective performance of the oxide layer is greatly reduced. The hydrogen barrier permeation behavior of the composite coating in a fusion reactor was simulated via hydrogen plasma discharge environment, the results show that the hydrogen barrier permeation performance of the composite is significantly better than that of a single TiO₂ coating. In addition, the coatings treated with hydrogen plasma showed a certain self-repairing performance through the diffusion growth of the TiC_x layer. These findings illustrate a novel method for preparing composite coatings to restrain hydrogen permeation, providing insight into the development of hydrogen permeation barrier materials.     

Graphene supported Pt–Ni bimetallic nanoparticles for efficient hydrogen generation from KBH4/NH3BH3 hydrolysis

Developing highly efficient and stable supported bimetallic nanoparticles catalysts via a facile strategy is one of the most admirable methods for sustainable hydrogen production from borohydride hydrolysis. Herein, we developed a facile technology for rapidly and straightforwardly manufacturing Pt–Ni bimetallic nanoparticles (BNPs) supported by partially reduced graphene oxide (prGO) with excellent catalytic activity and outstanding durability for hydrogen production from KBH₄ and NH₃BH₃ alkaline solution. The uniformly dispersed Pt₄₀–Ni₆₀ BNPs with a statistical size of around 2.6 nm exhibited a surprising catalytic activity of 23,460 mol-H₂·h^?1·mol-Pt^?1 at 308 K, moreover, whose activity was high up to 80% of the first time even after 30 runs, demonstrating an outstanding stability. The apparent activation energy for dehydrogenation of KBH₄ and NH₃BH₃ were respectively about 27.8 and 33.6 kJ/mol for the prepared Pt₄₀–Ni₆₀/prGO catalyst. The extraordinary catalytic activity of the Pt₄₀–Ni₆₀/prGO catalyst owing to the strong charge transfer effect between Pt–Ni BNPs and graphene.     

FeMoO4-graphene oxide photo-electro-catalyst for berberine removal and hydrogen evolution

Photo-electro-catalytic degradation of antibiotics such as berberine in water with simultaneous hydrogen evolution is an attractive option. It can control pollution using solar energy and provide clean energy. The photo electrodes play vital role in this kind of photocatalytic electrolytic cell. To obtain better electrode with high degradation capacity and fast hydrogen generation rate, using a facile one-pot hydrothermal process, a series of nano-structured composite FeMoO₄-GO (graphene oxide) catalysts with improved absorbance in 250–800 nm were synthesized, and loaded on CFC (carbon fiber cloth). Their photo electrode performance were compared. Using SEM(scanning electron microscope), XRD (X-ray diffraction) and XPS(X-ray photoelectron spectroscopy), the catalysts were characterized, and LSV(linear sweep voltammetry), CV(cyclic voltammetry) and EIS(electrochemical impedance) were used to characterize the electrodes. In 1 M KCl supporting electrolyte, at current density 10 mA cm⁻², 90% berberine was removed in 30 min and hydrogen generation rate was 3.1 μmol cm⁻² min⁻¹ in photo-electro-catalysis system. The results show rapid hydrogen generation and enhanced pollutant degradation.     

An overview of hydrogen generation by hydrolysis of Al and its alloys with the addition of carbon-based materials

Al and its alloys are studied extensively for hydrogen generation through water splitting. Alloying Al with metal activators such as bismuth, indium, gallium, etc., leads to the formation of micro galvanic cells during hydrolysis reaction, resulting in an improved hydrogen generation rate. Activation of Al by adding carbon-based materials such as graphite, carbon nanotubes (CNTs), graphene, etc., can instantaneously generate hydrogen at room temperature. When carbon particles are desorbed from the Al matrix during hydrolysis, new Al is exposed, resulting in an increased reaction rate. In Al-Graphite composites which form core-shell structures, H₂O molecules penetrate through the graphite layers and break down the core-shell structure during hydrolysis, and the new Al surfaces are exposed to water. It was found that Al with nano bismuth and graphene nanosheets showed better hydrogen generation rate and hydrogen yield. Graphene nanosheets control the agglomeration of Al and enhance the specific surface area for hydrolysis. During the hydrolysis of Al-CNTs composites, CNTs act as a cathode, resulting in galvanic corrosion between CNTs and the Al matrix. CNTs can also effectively control the agglomeration of Al during ball milling. Spark plasma sintered Al–Bi-CNT composites showed an enhanced hydrogen generation rate during hydrolysis. This paper presents an overview of hydrogen generation by hydrolysis of Al and its alloys, emphasising the addition of carbon-based materials such as graphite, graphene, CNTs, etc.     

Iron/carbon-black composite nanoparticles as an iron electrode material in a paste type rechargeable alkaline battery

Iron/carbon-black composite nanoparticles were synthesized by chemically reducing the iron salt mixing with carbon black by adding NaBH₄ in the aqueous solution. Carbon-black particles, with a mean particle size of approximately 40 nm, function as the nucleation cores for iron deposition. Additionally, core-shell iron composite particles are observed to be 30-100 nm with spherical sharp. At the first time discharge, the iron/carbon-black composite nanoparticle discharged 1200 mAh g⁻¹(Fe) at plateau one and 400 mAh g⁻¹at plateau two at a high current density of 200 mA g⁻¹(Fe). The capacity is larger than the theoretical value, which is attributed to the formation of iron hydride (FeH_x) while the iron was reduced by NaBH₄, followed the hydrogen reaction as an active material while the battery discharge occurs. In further cycles, the iron/carbon-black composite iron electrode shows a good reversibility of about 600 mAh g⁻¹(Fe) when the nickel-iron battery operated between 1.65 and 0.8 V. XRD analysis results indicate that the carbon black in the core of the iron/carbon-black composite enhances the reduction/oxidation reactions of iron, as achieved by the carbon black forming an enhanced electronic conductive network while iron is discharged as the insulator species such as Fe(OH)₂ and Fe₃O₄. SEM images reveal that the iron/carbon-black composite keeps particle sizes smaller than 300 nm during the electrode cycling, indicating that carbon black also acts as the nucleation cores for the dissolution-deposition of iron.     

Reduced graphene oxide-supported Ni-MoxC electrocatalyst for hydrogen evolution reaction prepared by ultrasonication and lyophilization

A Ni and Mo_xC hybrid (Ni-Mo_xC) supported on N-doped reduced graphene oxide (N-rGO) electrocatalyst with high hydrogen evolution reaction (HER) activity was prepared by ultrasonication and lyophilization. Notably, benefiting from the synergistic effect between Ni and Mo_xC nanoparticles, the optimized electrocatalyst displayed excellent catalytic activity with low overpotentials of 183 mV and 216 mV for the HER at the current density 10 mA cm⁻² in 1.0 M KOH and 0.5 M H₂SO₄ solution. The stability of the electrocatalyst could be well maintained for 24 h. These results indicate that the method to prepare hybrid (Ni-Mo_xC) is a simple way to produce cost-effective and high-efficient molybdenum carbide for hydrogen evolution.     

Highly dispersed Pd-MnOx nanoparticles supported on graphitic carbon nitride for hydrogen generation from formic acid-formate mixtures

Highly dispersed Pd and MnO_x nanoparticles supported on the graphitic carbon nitride with different composition have been prepared by a simple liquid deposition-reduction method and used as an efficient FA decomposition catalyst for hydrogen generation. The catalytic activity depends on the Pd-MnO_x composition of catalyst, the FA/SF ratio and the reaction temperature. The Pd-MnO_x/CN-1 catalyst exhibited excellent catalytic activity for hydrogen generation with the initial TOF of 465 h^?1 from formic acid-sodium formate mixture aqueous solution with a FA/SF ratio of 1:8 at 348 K. The synergetic effect between Pd nanoparticles and the carbon nitride support, the Mn/Pd ratios, the good dispersion of nanoparticles and the nature of the carbon nitride support were suggested to be responsible for the efficient catalytic performance of the Pd-MnO_x/CN nanocatalysts.