Acid Solution Research Articles

Chemical durability of optical temperature sensors made of tellurite glass: Effect of the alumina concentration

Tellurite glass is an amorphous material commonly doped with rare earth ions for the development of optical temperature sensors. Considering the intrinsic properties of glasses, it is expected that these sensors could be used in acidic environments and withstand temperature changes. However, this has not been fully demonstrated since most of the literature is limited to demonstrate the sensor operation under normal conditions. Additionally, there is a lack of information regarding the chemical durability of these glasses and methods to improve it. In this work, a special tellurite glass composition was proposed for the development of optical temperature sensor. The effect of the alumina concentration on the structure, chemical durability and emission properties of the glasses was evaluated. Chemical durability was assessed by monitoring the weight loss of glass samples after immersion in hydrochloric acid solutions at room temperature, vegetable oil or air at 150 °C. The results indicate that the addition of alumina increases the chemical durability of the glass and improves its emission properties. It was found that the average temperature estimated by the optical sensor had a relative error of 1.3 % due to the degradation of the glass caused by remaining immersed in a 1 N HCl solution for 60 days.

Влияние некоторых видов обработки на продолжительность сушки и органолептические показатели нарезанных баклажанов

Abstract. Eggplant is a common vegetable crop from the Solanaceae family, whose share of global vegetable harvests in 2022 was about 5 %. However, eggplant is thermophylic and its fruits cannot withstand low temperatures due to physiological disorders and quality reduction. This fact and thin covering tissues make the shelf life of eggplant fruits short. For this reason, improving existing methods for preserving the quality and extending the period of use of eggplants is relevant. One of the most popular methods of preserving fresh plant raw materials is drying, but it requires the selection of a method (including pre-treatment of raw materials) and process parameters to preserve the quality of dried products. In the course of the study, the influence of certain types of physical and chemical pre-treatment (microwave frequencies, citric acid, sodium chloride, their combinations) on the drying time and organoleptic characteristics of sliced eggplant fruits of the Chernomor variety was studied. It was found that various types of treatments used influenced the duration of drying of eggplants: treatments with microwave frequencies and citric acid led to a reduction in process time by 31-43 minutes compared to the control; treatments with sodium chloride solution and complex treatments, on the contrary, increased the duration by more than 3 hours. Organoleptic evaluation of dried eggplants showed that the best characteristics were provided by treatment with 1% and 5% citric acid solutions. While pre-treatment with microwave frequencies and NaCl with various parameters gave an unpleasant taste and was accompanied by darkening of the product. The data obtained can be used to improve existing methods of drying eggplants. Key words: eggplants, drying, organoleptic characteristics, super high frequency, citric acid, sodium chloride

Ferulic Acid in the Treatment of Papulopustular Rosacea: A Randomized Controlled Study.

Rosacea is a chronic inflammatory skin disease characterized by flushing, erythema, papules, and pustules on the central face. It affects patient appearance and is noted for its chronicity, recurrence, and resistance to treatment. Effective rosacea treatment requires repairing the skin barrier, reducing inflammation, and promoting vasoconstriction. This study aims to evaluate the efficacy of topical ferulic acid in treating papulopustular rosacea and its impact on skin barrier function. Sixty patients with mild to moderate papulopustular rosacea were selected from the Department of Dermatology at the Affiliated Hospital of Shandong Second Medical University between January 2023 and December 2023. Patients were randomly assigned to either a control group or an observation group, with 30 patients in each group. The observation group applied ferulic acid solution to the affected areas, while the control group used normal saline, both twice daily for 6 weeks. Both groups also received 0.1 g doxycycline hydrochloride tablets orally once daily. Skin lesions and skin barrier function were assessed using VISIA imaging and self-rating scales before and during treatment, and adverse reactions were recorded. After 6 weeks, both skin lesion assessments and self-assessment scores improved significantly from baseline, with greater improvement in the observation group compared to the control group (p < 0.05). Indicators of skin barrier function and VISIA imaging results demonstrated the efficacy of ferulic acid in treating rosacea. The total effective rate was significantly higher in the observation group (80.00%) compared to the control group (63.33%) (p < 0.05). In the observation group, nine patients (30.00%) experienced a greasy sensation initially, one patient (3.33%) reported tingling and itching, and no serious adverse reactions were observed. Ferulic acid is effective as an adjuvant treatment for papulopustular rosacea, significantly improving skin lesions and repairing skin barrier function with minimal adverse reactions.

Synthesis, characterization and performance of ecofriendly epoxy resin as a highly efficient corrosion inhibition for mild steel in 1m HCl solution

In this study, a novel epoxy resin called tetraglycidyl ether of methyl-α-D-mannopyranoside (TGEMM) was synthesized and investigated for its potential used as a corrosion inhibitor for mild steel in a 1.0 M hydrochloric acid (HCl) solution. The main goal was to evaluate the corrosion inhibition properties of TGEMM using various techniques. The methods used in this research included potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), temperature effect, scanning electron microscopy, energy dispersive X-ray spectroscopy, atomic force microscopy and contact angle measurement. These techniques were chosen to comprehensively assess the corrosion inhibition performance of TGEMM on MS. In this context, the structure of the newly synthesized TGEMM epoxy resin was identified and confirmed using Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). The results obtained from the experiments demonstrated that, at a lower concentration of 10−3 M, TGEMM demonstrated a high inhibitory efficacy of 91.49%, assessed via electrochemical impedance spectroscopy (EIS), and 93.84%, measured via potentiodynamic polarization (PDP), in a 1.0 M hydrochloric acid solution. The PDP data indicated that the TGEMM epoxy resin acted as an anodic inhibitor in the acidic environment. In addition to gain insights into the interaction mechanism and adsorption mode, DFT and MD simulations were conducted, revealing valuable information about the interaction of TGEMM with the mild steel surface.

Determination of trace uranium concentrations in spent‐fuel reprocessing using online graphite crystal pre‐diffraction energy‐dispersive x‐ray fluorescence

AbstractAn online graphite crystal pre‐diffraction x‐ray fluorescence technique was developed for accurate real‐time detection of trace uranium concentrations in spent‐fuel reprocessing streams. Online analysis for determining uranium concentrations was established. The device was equipped with measurement windows in both the flow cell and a side wall of the glove box. X‐ray tubes and detectors were arranged outside the glove box, and the process stream flowing through the flow cell was measured through the measurement window. A cylindrical highly oriented pyrolytic graphite crystal was located in front of the detector to improve detection efficiency and to provide monochromatic uranium‐characteristic x‐rays. At the same time, the device could perform remote online automatic calibration. The uranium detection limit in a kerosene solution was 0.08 mg/L, and the quantitative limit was 0.27 mg/L. The detection limit in a nitric acid solution was 0.11 mg/L, and the quantitative limit was 0.37 mg/L. The relative standard deviation of measuring 0.5 mg/L uranium was less than 10%, which greatly improved online monitoring of trace uranium in spent‐fuel reprocessing samples.

Investigating the Inhibitory Effect of Sargassum natans and Sargassum fluitans Extracts on Iron Corrosion in 1.00 mol L−1 HCl Solution

This study deals with the efficacy of extracts of Sargassum natans and Sargassum fluitans, an invasive brown algae present in Guadeloupe, as novel and environmentally friendly corrosion inhibitors for iron in 1 mol L−1 hydrochloric acid solutions. Six different Sargassum extracts (SE) were obtained using Soxhlet extraction with ethyl acetate, acetone, and ethanol, respectively, as solvents; cold successive maceration with chloroform and methanol, respectively; and microwave-assisted extraction with water. Subsequent electrochemical analysis showed that extracts from ethanol and ethyl acetate exhibited remarkable inhibition efficiencies of, respectively, 72.6% and 70.2%, but the better one was the extract of the cold maceration from chloroform with an inhibition efficiency of 92.0%. These findings allow us to focus on the chloroform extract (SEd) in order to see the change happening during the corrosion process via SEM and EDX analyses. Also, NMR analysis was conducted to identify the main chemicals responsible for the anticorrosion effect. The successful demonstration of the corrosion inhibitor effectiveness of extracts of Sargassum natans and fluitans suggests a potentially valuable use for this invasive biomass. These encouraging results warrant further investigation to identify and elucidate the active inhibitors in these extracts to deepen our understanding of their mechanisms for corrosion prevention and potentially expand their utility as an environmentally conscious approach to corrosion control.

Preparing efficient self-healing polyimide coating for enhancing stability of electromagnetic interference shielding film

Electromagnetic interference (EMI) shielding films were widely utilized in various electronic devices, but they were prone to damage and performance degradation in harsh environments. Therefore, it was urgent to maintain stable performance of EMI shielding films. In this work, we adopt the reactions between aldehyde-modified diamine monomers and dianhydride monomers with dynamic imine bond to successfully prepare a self-healing PI (SHPI) film. Benefit from dynamic imine and imide bond, the SHPI film possessed excellent thermal stability (T5 %=527.7°C), tensile strength (72 MPa) and self-healing efficiency (94.4 %). As protecting coating layer, the SHPI film was able to maintain the commercial aluminized polyimide (PI/Al) film with good EMI shielding performance in acid environment. The electromagnetic shielding film with self-healing coating still had average EMI shielding effectiveness value of 44.5 dB after exposed to 10 % concentration nitric acid solution for 30 min. It is noteworthy that when damaged by external forces, the electromagnetic shielding film with self-healing coating could achieve rapid healing, while the tensile strength was up to 87 MPa and the self-healing efficiency reached 92.5 %. This work provided an effective self-healing protective layer for EMI shielding material against corrosion in acidic environments and damage from external pressures.

Palladium(II) extraction from hydrochloric acid solutions with 2,6-bis[(methylsulfanyl)methyl]cyclohexan-1-one

Palladium(II) extraction from hydrochloric acid solutions with 2,6-bis[(methylsulfanyl)methyl]cyclohexan-1-one, obtained from natural methanethiol, was studied using chloroform as a diluent. Palladium(II) is recovered rapidly and with high efficiency by the extractant from solutions of 0.1–10 mol/L HCl and can be separated with high selectivity from Pt(IV), Cu(II), Ni(II), Zn(II) and Fe(III). A coordination mechanism of the palladium(II) extraction from 1 M HCl solutions was established. The extraction agent is coordinated to the Pd(II) ion through donor sulfur atoms in an extracted compound of the [PdCl2L] type. Stripping of Pd(II) is effectively carried out with a 1 M NH4OH solution or an acidic (0.1 mol/L HCl) thiourea solution.

Highly efficient bimetallic counter cations-based tungsten bronzes electrocatalysts developed for sustainable oxygen evolution in acidic solution

This study involves the designing of monophosphate tungsten bronzes (MPTBs) with a combination of earth-abundant Al and Ni counter cations synthesized via the solution combustion as robust, highly efficient electrocatalysts for oxygen evolution reaction (OER) in 1.0 M H2SO4 solution. A series of mixed Al and Ni counter cations-based MPTBs was prepared at different temperatures and characterized with various sophisticated techniques concerning their compositions, morphologies, microstates, and electronic states. The catalyst with Al/Ni ratio of 1:3 of tetragonal cube-shaped MPTB calcined at 700 °C ((Al1/3,Ni)-MPTB7) exhibited an extraordinary OER performance with a larger electrochemically active surface area, almost zero onset overpotential (η), and a lower solar cell-equivalent η (i.e., at 10 mA cm−2) of 199 mV that is lower than that obtained with the state-of-the-art RuO2 catalyst. A progressive enhancement of the performance of the catalysts was noticed for a 12 h OER run, ensuring the robustness of the materials developed for a long-term application. The mixed valency states of tungsten (W), i.e., W5+/W6+ states, along with higher oxygen vacancies of (Al1/3,Ni)-MPTB7 are evaluated to tender suitably oriented active sites for effective adsorption of H2O during the OER. A substantial increase in oxygen vacancies and W5+ state, particularly the W5+4f7/2 state in the catalysts, resulted from a spin-exchange phenomenon during a long-term OER is associated with OER catalytic enhancement. The thus-developed acid-stable, robust MPTBs with mixed Al and Ni counter cations would be an alternative to the pricy noble metal counterparts used in clean energy water splitting technology.

Electrodeposition of Cu 3D structures suitable for CO2 reduction

Porous Cu foam electrodes, suitable for cathodic CO2 reduction, were deposited in an acidic sulphate solution with different additives to obtain structures with a high real surface area and an adequate mechanical stability. The influence of the electrodeposition time and solution composition on the porosity parameters, microstructure and stiffness of Cu 3D structures was evaluated. Neither ammonium acetate nor polyethylene glycol were found to be effective additives to the Cu sulphate electrolyte to achieve the main objectives. Only the presence of Cl– ions in the deposition solution resulted in a threefold increase in the real surface area and the achievement of a sufficient mechanical stability of the Cu 3D structure. The latter effect is related to the specific influence of Cl– ions during the electrodeposition process on the microstructural characteristics, such as the size of micropores in the walls of holes and crystallite aggregates that form dendritic branches. These structural changes, in contrast to the Cu samples deposited in a solution without additives, resulted in larger real surface areas, while the denser structures deposited in the presence of Cl– ions ensured the mechanical stability of the 3D structure.

A pH Measurement of Acetic Acid-Sodium Acetate Buffer Solutions Using a pH Meter at Ambient Temperature

In article, we have reported the preparation of acetic acid-sodium acetate buffer solutions and determined its pH by using pH meter at about 25˚ C, as room temperature. In preparation of buffer solutions, firstly, we have taken 1.5 ml of glacial acetic acid into 100 ml of standard flask for making up 0.2M of acetic acid solution, and 0.64 gm of sodium acetate were dissolved into 100 ml distilled water. Then, taken 36.2 ml prepared solution of sodium acetate into 100 ml of standard flask and added 14.8 ml of prepared acetic acid to make its volume 100 ml by using distilled water, it is a buffer. In measuring the pH of prepared buffer solutions, we have been using a calibrated digital pen pH meter for quick resolution of reading with accuracy. The pH of acetic acid-acetate buffer solutions have gradually raised by adding small quantity of 5N NaOH solution into buffer sample, and adjusted pH was being to 4.7.

Potentiodynamic Polarization Study of PH3 Electrochemical Oxidation

ABSTRACTIn this study, the electrochemical behaviour of phosphine in sulphuric acid solutions on the surface of various electrode materials was conducted by voltammetric investigations. The effects of electrode materials such as lead, copper, and platinum electrodes on the PH3 anodic oxidation were investigated. Polarization curves were recorded by saturating the sulphuric acid solution with phosphine. The results received show that the electrochemical oxidation of phosphine on the lead electrode is accompanied by an oxygen evolution potential and, on the copper electrode, copper (II) ions show catalytic effects. The maximum anodic oxidation of phosphine on a platinum electrode was observed at the potential range of 0.8–1.0 V, and in the presence of copper (II) ions on the polarogram a maximum of phosphine oxidation is recorded at a potential of approximately 0.1–0.2 V.

Zeolite Crystallization Inside Chemically Recyclable Ordered Nanoporous Co3O4 Scaffold: Precise Replication and Accelerated Crystallization.

The synthesis of mesoporous zeolites has garnered attention with regard to improving their catalytic and adsorption performances. While the hard-templating method provides opportunities to design precisely controlled hierarchical micro- and mesoporous structures, synthesizing mesoporous zeolites without external precipitation requires significant work. This is mainly due to the absence of usable templates other than carbon with hydrophobic surfaces. Herein, it is demonstrated that the Co3O4 template is valuable in preparing mesoporous silicalite-1 and ZSM-5 with a precisely controlled porous structure through hydrothermal synthesis. Unlike conventional carbon templates, the Co3O4 template is relatively hydrophilic, effective in suppressing external precipitation, and is reusable by dissolving in an acidic solution. The crystallization process also differs from that of the carbon template, as the silicate precipitates on a 3D ordered nanoporous Co3O4 scaffold, followed by crystallization and crystal growth. Furthermore, it is unexpectedly observed that the zeolite crystallization is accelerated in the Co3O4 template. The synthetic approach utilizing nanoporous metal oxides opens new doors for the control of the hierarchical structure of zeolites, as well as for the design of metal oxide-zeolite nanocomposite catalysts, due to the potential extensibility of the combination of metal oxides and zeolites.

Ultra-Pressurized Deposition of Hydrophobic Chitosan Surface Coating on Wood for Fungal Resistance.

Fungi (Neolentinus lepideus, Nl, and Trametes versicolor, Tv) impart wood rot, leading to economic and environmental issues. To overcome this issue, toxic chemicals are commonly employed for wood preservation, impacting the environment and human health. Surface coatings based on antimicrobial chitosan (CS) of high molar mass (145 × 105 Da) were tested as wood preservation agents using an innovative strategy involving ultra-pressurizing CS solutions to deposit organic coatings on wood samples. Before coating deposition, the antifungal activity of CS in diluted acetic acid (AcOOH) solutions was evaluated against the rot fungi models Neolentinus lepideus (Nl) and Trametes versicolor (Tv). CS effectively inhibited fungal growth, particularly in solutions with concentrations equal to or higher than 0.125 mg/mL. Wood samples (Eucalyptus sp. and Pinus sp.) were then coated with CS under ultra-pressurization at 70 bar. The polymeric coating deposition on wood was confirmed through X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM) images, and water contact angle measurements. Infrared spectroscopy (FTIR) spectra of the uncoated and coated samples suggested that CS does not penetrate the bulk of the wood samples due to its high molar mass but penetrates in the surface pores, leading to its impregnation in wood samples. Coated and uncoated wood samples were exposed to fungi (Tv and Nl) for 12 weeks. In vivo testing revealed that Tv and Nl fungi did not grow on wood samples coated with CS, whereas the fungi proliferated on uncoated samples. CS of high molar mass has film-forming properties, leading to a thin hydrophobic film on the wood surface (water contact angle of 118°). This effect is mainly attributed to the high molar mass of CS and the hydrogen bonding interactions established between CS chains and cellulose. This hydrophobic film prevents water interaction, resulting in a stable coating with insignificant leaching of CS after the stability test. The CS coating can offer a sustainable strategy to prevent wood degradation, overcoming the disadvantages of toxic chemicals often used as wood preservative agents.

Setting reaction of a olivine-based Mg-phosphate cement

The cementitious properties of natural Mg-rich olivine when reacted with a phosphoric acid solution are investigated, as a function of acid concentration and liquid/solid mass ratio. The obtained cements are composed of residual olivine crystals and amorphous silica nanoparticles dispersed in a dense and compact newberyite (MgHPO4∙3H2O) matrix. The latter was mostly formed by packed micrometric tabular crystals, although evidence of the presence of a fraction of amorphous MgHPO4 was also found. Water content in the raw mix was observed to play a pivotal role on the reaction pathway, either promoting porosity or hindering the crystallization of the products. Up to 57 % of olivine reactivity, whose dissolution was promoted by the curing temperature (60 °C) and low pH, was achieved. All in all, these results indicate that the industrial mineral olivine may serve a viable source of Mg for the production of phosphate cements.

Accelerated failure behavior of Zr702 in boiling nitric acid solutions under constant stress loading

The constant stress tensile deformation behavior of commercial Zr702, used in spent fuel reprocessing industry, was investigated in 108 °C/200 MPa nitric acid solutions and non-corrosive silicone oil. Microscopic characterization of surface as well as cross-section of deformed Zr702 was carried out. In silicone oil, there were minimal cracks observed on the sample's surface. However, a significant number of cracks appeared on the sample's surface in nitric acid solutions. In nitric acid solutions, at the interface between the oxide layer and the matrix, cracks occurred, extended, the oxide film fractured, cracks further expanded, and the stress concentration at the cracks tip led to the formation of new cracks. This cyclic process resulted in the strength of the material decreasing and accelerated failure.

A Study on Acid Dissolution Characteristics and the Permeability Enhancement of Deep Coal Rock

In order to reveal the acidification and dissolution characteristics of deep coal rock, core acidification and dissolution experiments are carried out based on low-field nuclear magnetic resonance technology to study the dissolution characteristics of different acid types when applied to coal rock, and to quantitatively evaluate the dissolution characteristics of acid solutions when applied to different-scale pore throats and the karst corrosion characteristics of primary fractures. This will help to further understand the dissolution rate and pore volume growth rate of coal powder under the action of different acid types. Improving the seepage effect of coal seams is of great significance. The results show that 15% acetic acid has the best effect with regard to karst erosion and permeability. The pore volume growth rate is 442.49%, and the permeability increases by up to 31 times. With large pores, the rapid dissolution stage of mud acid, hydrochloric acid, and mixed acid mainly occurred in the first 36 h, and the rapid dissolution stage of acetic acid and hydrofluoric acid applied to the core mainly occurred at 36–72 h. The dissolution rate of acid solution is strongly correlated with porosity and permeability, and the higher the acetic acid concentration, the larger the permeability increase.

Liquid chromatography-mass spectrometric method for the simultaneous analysis of branched-chain amino acids and their ketoacids from dried blood spot as secondary analytes for the detection of maple syrup urine disease

BackgroundMaple syrup urine disease (MSUD) is an aminoacidopathy caused by a defective branched-chain alpha-ketoacid dehydrogenase complex, leading to the accumulation of branched-chain amino acids (BCAAs) and their respective keto acids (BCKAs). A comprehensive test was developed to measure BCAAs and BCKAs using LC-MS from dried blood spot (DBS) samples for the diagnosis and prevention of MSUD in newborns and infants. MethodsAnalytes were extracted from DBS using a methanol:0.1 % v/v formic acid solution (75:25) containing internal standards and analyzed on a Luna PFP column (150 mm × 4.6 mm, 3 µm) at a flow rate of 0.3 mL/min. The method was validated for linearity, accuracy, precision, recovery, carry-over, matrix effect, hematocrit, blood volume, and punch position effects. Biomarker stability in the matrix and stock solution was assessed. Correlation with the plasma method was determined using Pearson’s correlation coefficient and Bland-Altman analysis. The method established reference ranges for the Udupi district population in South India. ResultsThe method demonstrated linearity (r2 > 0.99), with a lower limit of detection at 2 µM (BCAA) and 1 µM (BCKA), and acceptable recovery of QC samples. Hematocrit, blood volume, punch position, and storage condition effects were within acceptable limits. Correlation and Bland-Altman analysis showed strong interconvertibility between plasma and DBS assays. Reference ranges for leucine, isoleucine, valine, KIC, KIV, and KMV were established. ConclusionThe developed DBS method, requiring no derivatization and involving simple sample preparation with short run times, is a cost-effective and reliable approach for the confirmatory diagnosis of MSUD.

Molding blends of silicone polymer / polypropylene with durable resistant to extreme conditions based on migration and compatibility of molecular chains

Because of low surface energy, silicone polymers would easily peel off from polypropylene (PP) substrate as hydrophobic coatings and they are incompatible with PP in melt-blending process as well. Therefore, ethylene polymers modified with both silicone and alkane side-groups were prepared by nucleophilic substitution in this work. It was confirmed that these prepared polymers could migrate and aggregate to the surface of the blends at that melting temperature when blended with PP due to the low surface energy and high entropy of silicone side groups. Meanwhile, chain entanglement was achieved between alky side-groups of silicone polymers and polymer chain of PP by melt-blending process, so that the compatibility of the blends was improved and the bonding force of two polymers increased simultaneously. Accordingly, molding blends with stable and durable hydrophobility were successfully gained based on migration of silicone and entanglement of alkane and PP. It’s noticeable that the water contact angle of the blend remained to be about 106° from 113°, even soaking in acid (pH = 1) and alkali (pH = 14) solutions, deionized water and anhydrous ethanol, or under multiple strong frictions. This will provide a facile and effective strategy to endow general materials with durable antifouling properties directly by injection molding without additional coating.

Pd nanoparticles on DUT-67-PZDC-derived N-doped carbon for efficient H2 generation from formic acid dehydrogenation

It is important to develop heterogeneous catalysts with high efficiency and stability to catalyze formic acid (FA, HCOOH) dehydrogenation. Herein, through pyrolysis of DUT-67-PZDC and etching in a hydrofluoric acid (HF) solution, the HF-etched N-doped carbon (HNDC) carrier was obtained. Palladium nanoparticles (Pd NPs), with an average particle size of 3.0 nm, were prepared on the HNDC support using a simple chemical co-reduction method. The optimized Pd/HNDC catalyst demonstrates excellent catalytic activity, the initial turnover frequency (TOF) value is 6001 h−1 at 50 °C with the incorporation of sodium formate (SF) as an additive, and the FA conversion and hydrogen (H2) selectivity could be up to 100%, which is comparable to the majority of MOF-derived heterogeneous catalysts published to date. Additionally, the Pd/HNDC can maintain good stability in five consecutive FA dehydrogenation runs with only a slight decrease. Such remarkable catalytic performance of Pd/HNDC is mainly ascribed to the unique structure of HNDC support with high surface area and hierarchical pore characteristic, the strong synergistic interaction between Pd NPs and the N sites on HNDC, as well as the ultrasmall size and high dispersion of Pd NPs as the catalytic active site. This work offers an efficient method for assembling highly active catalysts for FA dehydrogenation.