Fibrous Catalyst Research Articles

Fibrous catalyst based on atomic Pd and N-doped holey graphene functionalized cotton fiber for continuous-flow reaction

Continuous-flow catalysis bridges the gap between bench-scale laboratories and production-scale factories and thus should be a green and promising technology for the manufacture of value-added chemicals. Here, we present the construction of a continuous-flow catalytic system by integrating a tubular reactor with novel catalytic fibers, which are comprised of single-atomic Pd (Pd1) and nitrogen-doped holey graphene (NHG) functionalized cotton fibers (CFs). Due to the loosely packed structure, highly exposed dual-active sites (i.e., single-atomic PdN4 sites and activated C sites in the NHG carbocatalyst) of the CF@(Pd1/NHG) catalytic fibers, the corresponding flowing system exhibites remarkably high catalytic performance (activity and durability) and processing rate in organic reactions, including oxidative hydroxylation of phenylboronic acid and reduction of nitroarenes. Typically, the processing rate of the catalytic system toward 4-nitrophenol (a representative nitroarene) reduction can reach up to 2.46 × 10−3 mmol·mg−1·min−1, significantly higher than that of those packing catalysts reported in recent years.

Ultrahigh-Performance Fiber-Supported Iron-Based Ionic Liquid for Synthesizing 3,4-Dihydropyrimidin-2-(1H)-ones in a Cleaner Manner.

Herein, a fiber-supported iron-based ionic liquid as a type of fibrous catalyst has been developed for the synthesis of bioactive 3,4-dihydropyrimidin-2-(1H)-ones (DHPMs) via three-component Biginelli reactions in a cleaner manner. The described fibrous catalyst was obtained from the commercially available polyetheretherketone (PEEK) fiber by postfunctionalization processes and was characterized and analyzed in detail by means of diversified technologies. Furthermore, the fiber-supported iron-based ionic liquids could mediate the classical three-component Biginelli reactions to proceed smoothly to gain a variety of substituted DHPMs with yields of up to 99%. The superior catalytic activities of the fibrous catalyst were ascribed to the quasi-homogeneous medium by ionic liquids generated in the surface layer of the PEEK fiber, which could afford an appropriate reaction zone and could further be available for the aggregation of substrates to facilitate the three-component reaction. Notably, the fibrous catalyst is available for recycling over 10 runs just by a pair of tweezers, and the operational procedure was capable of enlarging the catalytic system to the gram-scale without any performance degradation, which provided a cleaner manner to take advantage of the iron-based catalyst in organic synthesis with potential industrialization prospects.

Fibrous catalyst flexibility as a source of mass transfer intensification

The work is devoted to computational fluid dynamics (CFD) simulation of structured cartridges with glass-fiber catalysts (GFCs). The CFD simulation of the model reaction of toluene deep oxidation at 350 °C in the cartridge with corrugated and plain structuring meshes (channel height 5.7 mm, width 8.0 mm, GFC length 44 mm) and sateen-type Pt-based GFC have confirmed the earlier formulated hypothesis, connecting their unusually high mass transfer efficiency with flexibility of GFCs, when the higher apparent transfer coefficient is provided by additional fluid flow in the back-side space of the textile thus leading to the rise of effective external contact surface area. The current study has revealed that relative effective surface area may vary from 1, equivalent to front-sided GFC contact only at low gas speed and up to 1.7 at higher velocities demonstrating that back-side flow may be quite significant even at quite moderate gas velocities (below 0.5 m/sec). The obtained knowledge may open the new approaches for development and optimization of structured GFCs.

Direct application of directly-spun carbon nanotube fiber as a fibrous nanocomposite catalyst for environmental remediation

Direct spinning process of carbon nanotube fiber (CNTF) is revisited as a scalable and continuous process to produce a fibrous nanocomposite catalyst for photocatalytic degradation of organic pollutants through photo-Fenton reaction. The directly-spun CNTF inevitably contains iron or iron oxide nanoparticles, which are widely used as a nanocatalyst for Fenton reaction, because they are essential catalysts to synthesize CNTF through decomposition of carbon source in chemical vapor deposition reaction. Therefore, CNTF is intrinsically a kind of nanocomposite fibers and has a strong potential to be utilized as a fibrous nanocomposite catalyst. Herein, it is demonstrated that CNTF is an efficient fibrous catalyst to decompose various organic pollutants through photo-Fenton reaction based on its stable reactivity in a wide pH range, weavability to prepare a textile (16 cm2), and recyclability without a structural deformation after washing and repeated usages.

Plasma-assisted deposition of Mn and Fe phases on CeO2 biomorphic fibers for soot combustion and CO oxidation

In the present work, the gliding arc (glidarc) plasma technique is for the first time explored as a novel precipitation-deposition method to generate fibrous catalysts. Precisely, Mn and Fe oxides were plasma-precipitated on a fibrous ceria support and evaluated in two reactions of environmental interest, (1) soot combustion and (2) CO oxidation. Pure CeO2 fibers (Fib Ce) were obtained via a biotemplate route with the idea of starting from a support already active in oxidation reactions, and then further improving its activity by supporting on its surface Fe and Mn oxides. The precipitates were identified by XRD, FTIR and LRS, and their loadings and distributions assessed by ICP and EDX respectively. α-Fe2O3 and Mn3O4 phases were detected. XPS confirmed the presence of Mn and Fe on the surface of Fib Ce and revealed that the deposition of Fe logically gave a superficial Fe/Ce ratio much higher than the bulk one and provoked an increase in Ce3+/Ce4+ and Oads/Ce ratios. On the contrary, Mn-supported samples did not affect considerably the Ce3+/Ce4+ and Oads/Ce ratios and presented a Mn/Ce ratio closer to that of the bulk. The latter suggests that Mn has integrated the ceria structure. For reaction (1), the deposition of Fe by plasma drastically degraded the performance of the bare support, whereas Mn deposition greatly increased the activity of Fib Ce. The same activity order was observed for reaction (2): Mn-Fib Ce > Fib Ce > Fe-Fib Ce.

Design and fabrication of the alumina nanofibers decorated with isolated ZSM-5 using electrospinning method: A novel catalyst for methanol conversion to light olefins

ZSM-5 nanoparticles are widely used as the catalyst in the methanol conversion to olefins (MTO) process due to their high surface area and short diffusion path length. However, agglomerate formation is a challenge for this catalyst. To address this issue, in this study, electrospinning was used for the first time to synthesize fibrous catalysts comprised of ZSM-5 nanoparticles embedded in the alumina nanofibers. The catalysts were characterized using XRD, FTIR, SEM, TEM, EDX-map, BET, and NH3-TPD analyses. In the synthesized samples, ZSM-5 nanoparticles with an average particle size of 683 nm are uniformly and homogeneously dispersed over alumina nanofibers with a 300 nm diameter. These composites form core-shell structures and have a reactor porosity of 0.85, which is higher than that of parent ZSM-5. In the MTO process, electrospun catalysts demonstrate superior catalytic activity and a longer lifespan than powder catalysts. 80 wt% ZSM-5- 20 wt% Al2O3 with 47.76 % light olefin selectivity and complete methanol conversion after 321min on stream performed better than 50 wt% ZSM-5-50 wt% Al2O3. Moreover, a lower coke formation of about 3.28 % was achieved for the 80 wt% ZSM-5- 20 wt% Al2O3 sample. The reduced bulk density of the electrospun samples increases the probability of reactant and catalyst contact. Additionally, electrospinning is an effective method for reducing particle aggregation and improving catalytic process efficiency.

Mn-doped carbon-Al2SiO5 fibers enable catalytic ozonation for wastewater treatment: Interface modulation and mass transfer enhancement

Heterogeneous catalytic ozonation is an efficient approach to remove hazardous and refractory organic contaminants in wastewater. It is crucial to design an ozone catalyst with high catalytic activity, high mass transfer and facile separation properties. Herein, easily separable aluminosilicate (Al2SiO5) fibers were developed as carriers and after interface modulation, Mn-doped carbon-Al2SiO5 (Mn-CAS) fibrous catalysts were proposed for catalytic ozonation. The growth of carbon shells on Al2SiO5 fiber surface and the introduction of metal Mn provided abundant Lewis acid sites to catalyze ozone. The Mn-CAS fiber/O3 system exhibited superior reactivity to degrade oxalic acid with a rate constant of 0.034 min−1, which was about 19 times as high as Al2SiO5/O3. For coal gasification wastewater treatment, Mn-CAS fibers also demonstrated high catalytic activity and stability and the COD removal was over 56%. Computational fluid dynamic simulations proved the high mass transfer properties of fibrous catalysts. Hydroxyl radicals (•OH) were identified as the predominant active species for organic degradation. Particularly, the catalytic pathways of O3 to •OH on Mn-O4 sites were revealed by theoretical calculations. This work provides a novel fibrous catalyst with high reactivity and mass transfer as well as easy separation characteristics for catalytic ozonation and wastewater purification.

Conductive core/shell polymer nanofibres as anode materials for direct ethanol fuel cells

A conductive polymer-supported electrocatalyst in the form of fibrous mat has been developed that can be employed as a polymer-based electrode for direct ethanol fuel cells (DEFCs) with promoting effects to the state-of-the art Pd based catalysts. A series of conductive polyaniline (PANI)-containing polymer fibres-supported Pd electrocatalytic electrodes were successfully prepared and tested for the ethanol electro-oxidation reaction (EOR) in alkaline medium. The polymer support was a robust fibrous mat, where the fibres possessed a core-shell configuration. The core part was produced via electrospinning using a mixture of polyacrylonitrile (PAN) and 1-butyl-3-methylimidazolium chloride [BMIm]Cl ionic liquid (IL). The shell was a PANI layer deposited via the chemical polymerisation of aniline monomer. Pd was then electrodeposited on the fibres and the catalysts were tested for the EOR via cyclic voltammetry (CV) in a half-cell configuration and in a temperature range between 25 and 60 °C. The activity of the catalysts tested was measured in terms of activation energy and forward peak current density in the CV and compared to that of glassy carbon (GC)-supported Pd/PANI/PAN/IL fibrous catalysts. The polymer fibre-catalyst samples showed a higher active surface area and significantly lower activation energy than the GC-based ones. Even though the GC-supported catalysts showed a higher activity in terms of current, the Pd/(PAN/IL)-core/PANI-shell fibrous mats were active as well and, in some cases, demonstrated a promoting effect of PANI on Pd for EOR and a much better stability and robustness compared to the former. Furthermore, a series of promoting metals were investigated for these mats, such as Ag, Bi and Cu, with Ag and Bi demonstrating promoting effects compared to monometallic Pd/(PAN/IL)-core/PANI-shell mats in terms of both activation energy and peak current density. This work demonstrates a promising strategy in the arena of development of polymeric mats as anode electrodes for DEFCs, exploiting the benefits of PANI in terms of ease of synthesis, catalyst poisoning prevention, cost and promoting effects.

Facile fabrication of porous carbon nanofibers encapsulated with nanoscale exposed Ni for producing high-purity hydrogen from cheap glycerol

Transition metal nanoparticles supported on porous carbon materials as hydrothermal stable and highly effective catalysts are increasingly attracting worldwide attention. Herein, a controllable electrospinning technique was employed to prepare the promising catalysts to produce hydrogen. Different proportions of polymethyl methacrylate and nickel nitrate were introduced into polyacrylonitrile spinning solution to prepare nanoscale Ni encapsulated in porous carbon nanofiber (Ni@PCNF) through an in-situ pore-making strategy. The results show that the prepared 10 wt% Ni@PCNF catalyst possesses an enhanced specific surface area, hierarchical porous structure, and uniformly-dispersed Ni nanoparticles (∼17 nm). This porous and fibrous catalyst presents relatively high performance of producing high-purity H2 by aqueous phase reforming of glycerol compared with several reference catalysts on different supports (e.g., activated carbon fibers and γ-Al2O3) under similar reaction conditions. The selectivity and purity of H2 produced by 10 wt% Ni@PCNF catalyst at 260 °C for 1 h are nearly 100% and 93%, respectively. This is related to the moderate catalytic activity of active Ni nanoparticles encapsulated in PCNFs. By contrast, those Ni nanoparticles supported on the reference supports show a high catalytic activity and thus produce low-purity H2 due to the considerable byproducts of CH4, CO and CO2. Moreover, Ni@PCNF catalyst exhibits a good structure stability and reuse effect in comparison with reference catalysts. This work provides a roadmap for preparing effective and stable Ni-based catalysts to produce high-purity H2 from cheap glycerol through a low-temperature thermocatalysis.

In situ growth of Cu(BDC) on microscale Cu‐based carboxymethylcellulose fibers: A new strategy for constructing efficient catalysts for A3‐coupling reactions

Based on the coordination properties of carboxylates in carboxymethylcellulose (CMC) and metal ions, we have prepared microscale Cu‐based carboxymethylcellulose fibers (Cu(II)/CMC) by extruding the CMC‐Na solution into a Cu(II) ions coagulation bath. We found that the as‐obtained microscale Cu(II)/CMC fibers are well suitable for the in situ growth of the copper terephthalate (Cu(BDC)) MOFs directly from the coordinated Cu(II) sites enriched on the surface of fibers (Cu(BDC)@Cu(II)/CMC) in the terephthalic acid solution. The composition and structure of Cu(BDC)@Cu(II)/CMC composite fibers were verified using various FTIR, XRD, SEM, EDX, elemental mapping, XPS, TGA, and BET tools. The characterized data revealed that well‐defined Cu(BDC) particles were distributed uniformly on the surface of the microscale Cu‐based fibers. The resulting Cu(BDC)@Cu(II)/CMC fibers were used as an effective and retrievable heterogeneous catalyst for the aldehyde‐alkyne‐amine (A3) coupling reactions. The superior catalytic activity is attributed to the excellent dispersion and stability of the Cu(BDC) MOFs crystallites containing the numerous active Cu(II) sites on the microscale fibers. In addition, the microscale fibrous catalyst can be conveniently retrieved with tweezers after each cycle and reused at least six times without a significant drop in its activity.

Quaternary ammonium salt functionalized polyetheretherketone fiber: A novel fibrous material for phase-transfer catalysis

Herein, the commercially available ultra-high-strength textile fiber polyetheretherketone (PEEK) was directionally functionalized by afterward immobilization procedures to graft quaternary ammonium salts into its surface layer, and the resulted fibrous materials were capable of acting as the heterogeneous-supported phase-transfer catalysts were presented in the etherification of halogenated nitrobenzenes for the synthesis of nitroanisoles. The acquiring fiber samples from different processes were observed and characterized detailedly by diversified technologies of morphologies, mechanical properties, elemental analysis, FTIR spectroscopy, X-ray diffraction, and thermogravimetric analysis to confirm the reliability of this methodology. Moreover, the effect of functionalized degree on the PEEK fiber was inspected, and the phase-transfer catalytic system mediated by the fibrous material showed superior performance in terms of simple procedures, high yields of nitroanisoles (up to 99%), and excellent recyclability (over 30 cycles). Additionally, the newly developed fibrous catalyst exhibited superior stability (at least for 4 months) and effectively gram-scale operation in a concise spinning basket reactor, which is very attractive for various phase-transfer catalysis reactions in chemical productions.

Pd/C embedded crosslinked polystyrene fibers as an efficient catalyst for Heck reactions

AbstractPd/C embedded polystyrene fibers were successfully prepared by electrospinning. The polystyrene molecules were then cross‐linked by paraformaldehyde in sulfuric acid to improve the solvent resistance of composite fibers. SEM images conformed the preparation of uniform and smooth composite fibers. FT‐IR spectra demonstrated that the polystyrene molecules inside fibers have been sulphonated and crosslinked. Heck reactions were used to evaluate the catalytic performance of these novel composite fibers. The catalysis results show that this composite fiber mat catalyzed Heck reactions could be evidently promoted by using preferred reducing alcohol agent and solvent. Under the optimized reaction conditions, this composite fiber mat could effectively catalyze the Heck reactions of aromatic iodides with n‐butyl acrylate to afford the products with satisfied yields. Especially, compared with the particulate Pd/C catalyst, the separation and recycling of this fibrous catalyst from the reaction mixture were significantly improved due to the larger fibrous structure. At last, this fiber catalyst was successfully reused for eight times with little loss of initial catalytic activity, which was even better than the pristine Pd/C catalyst. Hence, embedment of particulate supported metal catalysts inside the crosslinked polystyrene fibers can effectively improve their catalytic performance and handiness.

Simulation Study of Ceramic Fibrous Structured Catalysts for CO2 Methanation—Enhancement of the Performance and Comparison to Pellet Catalysts

Simulation Study of Ceramic Fibrous Structured Catalysts for CO2 Methanation—Enhancement of the Performance and Comparison to Pellet Catalysts

Acid–base bifunctional catalysis by a heteropolyacid and amines on the polyetheretherketone fiber for cleaner acceleration of the one-pot tandem reactions

The development of highly efficient, economical and environmentally friendly catalytic systems is of great significance from the green chemistry point of view. In this paper, we presented a succinct approach to create a heterogeneous acid–base bifunctional catalyst for one-pot tandem reaction from the commercially available textile fiber. The ultra-high strength textile fiber polyetheretherketone (PEEK) was functionalized by a post-grafting method to combine two antagonistic active functions in a synergistic catalyst, and the resulting fiber samples were characterized in detail by morphology, mechanical properties, elemental analysis, X-ray photoelectron spectroscopy, inductively coupled plasma-atomic emission spectrometry, X-ray diffraction, Fourier transform infrared spectroscopy, ultraviolet–visible spectrum, nuclear magnetic resonance spectroscopy and thermogravimetric analysis, and further revealed that the amines and the heteropolyacid were immobilized by acid–base interactions in the PEEK surface layer with sufficient stability. Moreover, the acid–base bifunctional catalyst can be successfully applied in the acceleration of the one-pot tandem deacetalization–Knoevenagel reactions with high-efficiency (lower catalyst dosage 0.3 mol%, higher product yields 81–92%), whereas the homogeneous catalysts were unable to initiate the reaction due to their mutual neutralization in solution, and the catalytic mechanism was elucidated by comparison. Furthermore, the fibrous catalyst could maintain its activities more than 10 cycles with a simple post-processing, and the mediated system was capable of enlarging to the gram-scale, which are envisaged for industrial operations and cleaner productions.

Robust Ni nanocatalysts formed by exsolution from nanofibrous fluorite ceramic supports for methane partial oxidation

Exsolution is a promising approach to prepare catalysts with both high metal catalyst dispersion and the strong metal/support interaction. Exsolved metal catalysts from conventional perovskite ceramics experience the limitation of reversible exsolution, which makes exsolved metal catalysts instable in the presence of oxidant, such as oxygen during methane partial oxidation (POM). This study has demonstrated stable Ni nanocatalysts exsolved from Y-doped ZrO2 (YSZ) fluorite ceramic after NiO dissolution. The NiO dissolution was promoted through tuning Y-doping and elevating calcination temperature owing to the thermally-stable structure of fibrous catalysts. The robust Ni/YSZ catalysts generated a high methane conversion of about 79.5 % during the POM at 750 °C, which was stable during the test for 100 h owing to the stable Ni catalysts. Therefore, metal exsolution from fibrous fluorite ceramics represents an effective way to prepare efficient and stable nanocatalysts for catalytic redox reactions.

Tuning the Polarity of a Fibrous Poly(vinylidene fluoride-co-hexafluoropropylene)-Based Support for Efficient Water Electrolysis.

Water electrolysis under alkaline conditions is of interest due to the applicability of non-precious metal-based materials for electrocatalysts. However, the successful design and synthesis of earth-abundant and efficient catalysts for the oxygen evolution reaction (OER) remain a significant challenge. This work presents cost-effective and straightforward ways to improve the OER activity under alkaline conditions by activating the catalyst–support and reactant–support interaction. Micro/nano-sized fibrous poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) was synthesized via simple and scalable electrospinning and subsequently coated with Cu by electroless deposition to obtain the electrocatalyst with a large specific surface area, enhanced mass transport, and high catalyst utilization. Scanning electron microscopy, infrared spectroscopy, and X-ray diffraction confirmed the successful synthesis of the series of Cu/PVdF-HFP fibrous catalysts with varied ferroelectric polarizability of the PVdF-HFP support in the order of stretch-anneal > anneal > stretch > without pre-treatment of the catalyst. The best OER activity was confirmed for the Cu/PVdF-HFP catalyst with stretch and annealed treatment among the catalysts tested, suggesting that both the reaction kinetics and energetics of stretch-annealed Cu/PVdF-HFP catalysts were optimal for the OER. The electron delocalization between Cu and PVdF-HFP substrates (electron transfer from Cu to the negatively charged (δ–eff) PVdF-HFP region at the Cu|PVdF-HFP interface) and the enhanced transport of reactive hydroxide species and/or the increase in the local pH by positively charged (δ+eff) PVdF-HFP region concertedly accelerate the OER activity. The overall activity for the prototype water electrolyzer increased 10-fold with stretch-anneal treatment compared to the one without pre-treatment, highlighting the effect of tuning the catalyst–support and reactant–support interaction on improving the efficiency of the water electrolysis.

Ultrafine palladium nanoparticles confined in polydopamine functionalized chlorinated poly(vinyl chloride) nanofibers for Heck reaction

AbstractPolydopamine has been considered as the adhesive of mussels to solid surfaces in biological systems. The development of dopamine and polydopamine functionalized nanofibrous materials is highly desirable for catalysis, drug delivery and tissue engineering. Polydopamine induced surface functionalized solid matrices have been proved to be efficient supporting materials for palladium nanoparticles. In this study, the dopamine monomers were first incorporated into the Pd2+/chlorated poly(vinyl chloride) (CPVC) composite nanofibers by electrospinning and then polymerized in basic and reductive solution at elevated temperature to prepare stable polydopamine functionalized CPVC supported palladium composite nanofibers. Scanning electron microscopy images show that uniform and smooth nanofibers with diameter of ~325 nm have been prepared and high temperature can promote their solvent resistance. Fourier transformed infrared and UV–visible (UV–Vis) spectra confirmed the synthesis of polydopamine inside the composite nanofibers. The ultrafine palladium nanoparticles inside the composite nanofibers were characterized by X‐ray spectroscopy and transmission electron microscopy. Although these palladium nanoparticles were confined inside the nanofibers, they exhibited excellent catalytic efficiency for the Heck reactions of aryl iodides with alkenes. Moreover, this novel fibrous catalyst could be easily recovered by simple filtration and reused at least five times without obviously loss of initial catalytic activity. In all, we have developed a distinctive way for the synthesis of polydopamine functionalized polymeric materials for catalysis and other applications.

Elevated-temperature bio-ethanol-assisted water electrolysis for efficient hydrogen production

Steam electrolysis over solid oxide electrolysis cells (SOECs) is a promising technique to store renewable power (such as solar and wind power) into hydrogen, and bio-ethanol-assisted steam electrolysis not only increases energy conversion efficiency but also store bio-mass energy into valuable fuels. This study developed SOEC-type reactors for conducting ethanol-assisted water electrolysis for the first time. Conventional catalytic steam reforming of ethanol for hydrogen production consumes a lot of heat and includes a complicated process, while the ethanol-assisted water electrolysis can achieve thermoneutral operation at the electrolysis potential of 0.36 V and generate heat at the electrolysis potentials of above 0.36 V, simultaneously obtaining pure hydrogen from cathode chamber by one step. Micro-reformer constructed by loading fibrous catalysts within channeled anode supports performed efficient ethanol reforming to facilitate fuel oxidation on anode and hence promote steam electrolysis on cathode. Employing Ni-based materials for both anode and cathode enables the co-sintering of three layers of SOEC components, resulting in low cell resistances and stable electrolysis at a record high current density of 3.0 A cm−2 under a low overall cell voltage of less than 1.3 V. Therefore, this study has demonstrated an efficient way to generate green hydrogen energy from renewables.

Impact of heat transport properties and configuration of ceramic fibrous catalyst structures for CO2 methanation: A simulation study

Fibrous catalysts have shown to enhance mass transfer when applied to potentially limited reactions, and exhibit promising characteristics for heat transfer as well. However, heat removal seems to be the main limitation to process intensification when applying fibrous catalysts to an exothermic reaction. This paper investigates strategies to improve the heat transfer behavior of ceramic paper catalysts, by applying them to the exothermic reaction of CO2 methanation. A fixed-bed reactor model was used to simulate and study the development of temperature profiles, as well as the efficiency losses caused by insufficient heat removal. Different strategies were implemented in simulations to evaluate their impact on the management of reaction heat and hot-spots. The results bring forward the advantages and versatility of catalytic ceramic papers and other fibrous catalysts, as alternatives for process intensification, and to improve overall reactor performance in exothermic reaction applications.

Palladium nanoparticles encapsulated in polyimide nanofibers: An efficient and recyclable catalyst for coupling reaction

In this study, palladium‐encapsulated poly(amic acid) (Pd@PAA) nanofibers were prepared by electrospinning, followed by thermal imidization to synthesize palladium‐encapsulated polyimide (Pd@PI) nanofibers. Scanning electron microscopy (SEM) images confirmed the preparation of uniform and smooth Pd@PAA and Pd@PI nanofibers. Thermogravimetric analysis (TGA) results reveal that the Pd@PI nanofibers possessed excellent thermal stability. The dispersion of palladium nanoparticles in the polyimide nanofibers was characterized by transmission electron microscopy (TEM) and X‐ray diffraction (XRD). The catalysis results show that this Pd@PI fibrous catalyst was very efficient to catalyze the cross‐coupling reactions of aromatic iodides with n‐butyl acrylate (Heck reaction) or phenylboronic acid derivatives (Suzuki reaction) to afford the desired products in good to excellent yields. Moreover, the Pd@PI catalyst could be easily separated and recovered from the reaction mixture by simple filtration due to the regular fibrous structure and reused for 10 times for both Heck and Suzuki reactions without obvious loss of its initial catalytic activity. Thus, the Pd@PI nanofiber catalyst holds great potential in chemical industry in terms of its excellent catalytic activity and stability.