Search

The objective of this research is to propose some new fixed point theorems for fuzzy-dominated operators that satisfy a nonlinear contraction on a closed ball in a complete b-multiplicative metric space. Our strategy involves the use of a combination of two distinct kinds of mappings: one belongs to a weaker class of strictly increasing mappings, and the other is a class of dominated mappings. In order to demonstrate the validity of our new findings, we provide instances that are both illustrative and substantial. Finally, in order to illustrate the novelty of our findings, we provide applications that allow us to derive the common solution to integral and fractional differential equations. Our findings have a significant impact on the interpretation of a large number of previously published studies, both present and historical. [ABSTRACT FROM AUTHOR]

This article exhibits the thermoelastic interactions because of a consistent heat source in an isotropic, homogeneous, unbounded elastic solid with regards to the modified theory of thermoelasticity without energy dissipation. A novel modification for the three-phase-lag Green–Naghdi (TPL G–N) heat conduction equation is proposed for this purpose. A new potential function is employed to help in solving the present problem together with Laplace and Hankel transforms. After inverting Laplace transforms, the small-time approximated solutions are used to obtain expository expressions for the field variables inside the medium. The trend of variations in all quantities past the elastic wavefront to the heat wavefront is investigated. The quantities suddenly bounce to a high worth just previously the situation of the heat wavefront and from that point hop again to zero qualities. [ABSTRACT FROM AUTHOR]

This article has been devoted to investigating the thermoelastic diffusion problem of an infinite medium. The simple and refined single/dual-phase-lag Green–Naghdi models with and without energy dissipation are proposed. The exact solution of thermodiffusion coupling equations has been obtained considering the regularity conditions. The distributions of the non-dimensional temperature, dilatation, displacement, stresses, concentration and chemical potential are obtained and illustrated graphically. The validity of results is acceptable by comparing all outcomes. Benchmark results are reported to help other investigators in their future comparisons. [ABSTRACT FROM AUTHOR]

The aim of this article is to study the cone b-metric spaces over Banach Algebra with solid cones and establish some fixed points of multivalued mappings in this setting. Our results generalize and extend several known results of metric, cone metric and cone b-metric spaces. An example and certain consequences are presented to illustrate significance of established results. [ABSTRACT FROM AUTHOR]

In this paper, we prove some fixed point results for generalized contractive multimaps with respect to generalized distance. Consequently, several known fixed point results either generalized or improved including the corresponding recent fixed point results of Ciric, BinDehaish-Latif, Latif-Albar, Klim-Wardowski, Feng-Liu. [ABSTRACT FROM AUTHOR]

The aim of this paper is to establish some new fixed point results for Ćirić type α-η-GF-contraction in a complete metric space. We extend the con-cept of F-contraction and introduce the notion Ćirić type α-η-GF-contraction. An example is given to demonstrate the novelty of our work. [ABSTRACT FROM AUTHOR]

In this paper, we prove some fixed point results for generalized con-tractive multimaps with respect to generalized distance. Consequently, several known fixed point results either generalized or improved including the corresponding recent fixed point results of Ciric, BinDehaish-Latif, Latif-Albar, Klim-Wardowski, Feng-Liu. [ABSTRACT FROM AUTHOR]

The aim of this paper is to establish some new fixed point results for Ćirić type α-η-GF-contraction in a complete metric space. We extend the concept of F-contraction and introduce the notion Ćirić type α-η-GF-contraction. An example is given to demonstrate the novelty of our work. [ABSTRACT FROM AUTHOR]

In this paper, we prove sharpened versions of some classical order-theoretic metrical fixed point theorems due to Nieto and Rodríguez-López (Order 22(3):223-239, 2005) using order-theoretic variants of completeness and continuity besides some another notions such as: the ICC property, the DCC property, and the MCC property. In this continuation, we further extend our results for Boyd-Wong type nonlinear contractions. Finally, as an application of our certain newly proved results, we establish the existence and uniqueness of solution of a first order periodic boundary value problem. [ABSTRACT FROM AUTHOR]

In this work, we establish some fixed point theorems by revisiting the notion of ψ-contractive mapping in Menger PM-spaces. One of our results (namely, Theorem 2.3) may be viewed as a possible answer to the problem of existence of a fixed point for generalized type contractive mappings in M-complete Menger PM-spaces under arbitrary t-norm. Some examples are furnished to demonstrate the validity of the obtained results. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the notion of a conditionally F-contraction in the setting of complete metric-like spaces and we investigate the existence of fixed points of such mappings. Our results unify, extend, and improve several results in the literature. [ABSTRACT FROM AUTHOR]

In this paper, we generalize the Pecaric work on Montgomery's identity via an arbitrary weight function, which no longer needs to be a probability density function, and apply it to derive some generalized Chebyshev type inequalities for any absolutely continuous function. [ABSTRACT FROM AUTHOR]

We first introduce a new class of contractivemappings in the setting of metric spaces and then we present certain Greguš type fixed point theorems for such mappings. As an application, we derive certain Greguš type common fixed theorems. Our results extend Greguš fixed point theoreminmetric spaces and generalize and unify some related results in the literature. An example is also given to support our main result. [ABSTRACT FROM AUTHOR]

Let (X, d) be a complex valued metric space and let S, T bemappings from X to a set of all fuzzy subsets of X .We present sufficient conditions for the existence of a common α-fuzzy fixed point of S and T. Our results improve and extend certain recent results in literature. Moreover, we discuss an illustrative example to highlight the realized improvements. [ABSTRACT FROM AUTHOR]

The aim of this paper is to unify the concept of greatest lower bound (g.l.b) property and establish some generalized common fixed results. We support our results by a nontrivial example. [ABSTRACT FROM AUTHOR]

The aim of this paper is to define weak α-ψ-φ-contractive mappings and to establish coupled and tripled coincidence point theorems for such mappings defined on Gb-metric spaces using the concept of rectangular G-α-admissibility. As an application, we derive new coupled and tripled coincidence point results for weak ψ-φ-contractive mappings in partially ordered Gb-metric spaces. Our results are generalizations and extensions of some recent results in the literature. We also present an example as well as an application to nonlinear Fredholm integral equations in order to illustrate the effectiveness of our results. [ABSTRACT FROM AUTHOR]

The aim of this paper is to obtain some new integral type fixed point theorems for nonself weakly compatible mappings in symmetric spaces satisfying generalized (ψ, φ)-contractive conditions employing the common limit range property We furnish some interesting examples which support our main theorems. Our results generalize and extend some recent results contained in Imdad et al. (2013) to symmetric spaces. Consequently, a host of metrical common fixed theorems are generalized and improved. In the process, we also derive a fixed point theorem for four finite families of mappings which can be utilized to derive common fixed point theorems involving any number of finite mappings. [ABSTRACT FROM AUTHOR]

We obtained some generalized common fixed point results in the context of complex valued metric spaces. Moreover, we proved an existence theorem for the common solution for two Urysohn integral equations. Examples are presented to support our results. [ABSTRACT FROM AUTHOR]

We introduce the new type of nonself mapping and study sufficient conditions for the existence of past-present-future (for short PPF) dependent fixed point for such mapping in the Razumikhin class. Also, we apply our result to prove the PPF dependent coincidence point theorems. Finally, we use PPF dependence techniques to obtain solution for a nonlinear integral problem with delay. [ABSTRACT FROM AUTHOR]

We study Ulam-Hyers stability and the well-posedness of the fixed point problem for new type of generalized contraction mapping, so called α-λ-contraction mapping. The results in this paper generalize and unify several results in the literature such as the Banach contraction principle. [ABSTRACT FROM AUTHOR]

We introduce and study the notion of common coupled fixed points for a pair of mappings in complex valued metric space and demonstrate the existence and uniqueness of the common coupled fixed points in a complete complex-valuedmetric space in view of diverse contractive conditions. In addition, our investigations are well supported by nontrivial examples. [ABSTRACT FROM AUTHOR]

We define the notion of α*-Ψ-contractive mappings for cone metric space and obtain fixed points of multivalued mappings in connection with Hausdorff distance function for closed bounded subsets of cone metric spaces. We obtain some recent results of the literature as corollaries of our main theorem. Moreover, a nontrivial example of α*-Ψ-contractive mapping satisfying all conditions of our main result has been constructed [ABSTRACT FROM AUTHOR]

We introduce two new concepts of weakly relaxed η-α monotone mappings and weakly relaxed η-α semimonotone mappings. Using the KKM technique, the existence of solutions for variational-like problems with weakly relaxed η-α monotone mapping in reflexive Banach spaces is established. Also, we obtain the existence of solution for variational-like problems with weakly relaxed η-α semimonotone mappings in arbitrary Banach spaces by using the Kakutani-Fan-Glicksberg fixed-point theorem. [ABSTRACT FROM AUTHOR]

We introduce the concept of the generalized wα-contraction mappings and establish the existence of fixed point theorem for such mappings by using the properties of w-distance and α-admissible mappings. We also apply our result to coincidence point and common fixed point theorems in metric spaces. Further, the fixed point theorems endowed with an arbitrary binary relation are also derived from our results. Our results generalize the result of Kutbi, 2013, and several results in the literature. [ABSTRACT FROM AUTHOR]

We obtain some new estimates for the error of Simpson integration rule, which develop available results in the literature. Indeed, we introduce three main estimates for the residue of Simpson integration rule in L1[a, b] and L8[a, b] spaces where the compactness of the interval [a, b] plays a crucial role. [ABSTRACT FROM AUTHOR]

Using the generalized Caristi's fixed point theorems we prove the existence of fixed points for self and nonself multivalued weakly w-contractive maps. Consequently, Our results either improve or generalize the corresponding fixed point results due to Latif (2007), Bae (2003), Suzuki, and Takahashi (1996) and others. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to study the existence of fixed points for contractive-type and nonexpansive-type multivalued maps in the setting of modular function spaces. We also discuss the concept of w-modular function and prove fixed point results for weakly-modular contractive maps inmodular function spaces. These results extend several similar results proved in metric and Banach spaces settings. [ABSTRACT FROM AUTHOR]

• A novel model is presented to study thermoelastic diffusion behavior of a 1D half-space. • The RPL, G–L, L–S and classical models of thermoelasticity are mutual into a unified formulation. • The exact solution of motion, heat conduction and mass diffusion equations has been obtained. • Solutions are considered to define the thermoelastic diffusion behavior of the medium. • The validity of results is acceptable by comparing the present model with those due to other theories. This paper presents a novel multi-phase-lag model to study the thermoelastic diffusion behaviour of a one-dimensional half-space. The multi-phase-lag, the Green–Lindsay, the Lord–Shulman models as well as the classical theory of thermoelasticity are mutual into a unified formulation. The exact solution of three coupled equations, namely; motion, heat conduction and mass diffusion equations; has been obtained. Solutions determining for initial and boundary conditions are considered to define the thermoelastic diffusion behavior of the medium. The validity of results is acceptable by comparing the temperature, dilatation, displacement, stresses, concentration, and chemical potential according to the present multi-phase-lag theory with those due to other thermoelasticity theories. [ABSTRACT FROM AUTHOR]

The aim of this present paper is to study zero points of the sum of two maximally monotone mappings and fixed points of a non-expansive mapping. Two splitting projection algorithms are introduced and investigated for treating the zero and fixed point problems. Possible computational errors are taken into account. Two convergence theorems are obtained and applications are also considered in Hilbert spaces [ABSTRACT FROM AUTHOR]

Fuzzy set is a modern tool for depicting uncertainty. This paper introduces the concept of fuzzy sub e-group as an extension of fuzzy subgroup. The concepts of identity and inverse are generalized in fuzzy sub e-groups. Every fuzzy subgroup is proven to be a fuzzy sub e-group, but the converse is not true. Various properties of fuzzy sub e-groups are established. Moreover, the concepts of proper fuzzy sub e-group and super fuzzy sub e-group are discussed. Further, the concepts of fuzzy e-coset and normal fuzzy sub e-group are presented. Finally, we describe the effect of e-group homomorphism on normal fuzzy sub e-groups. [ABSTRACT FROM AUTHOR]

In this article, we familiarize a subclass of Kamali-type starlike functions connected with limacon domain of bean shape. We examine certain initial coefficient bounds and Fekete-Szegö inequalities for the functions in this class. Analogous results have been acquired for the functions f − 1 and ξ / f ξ and also found the upper bound for the second Hankel determinant a 2 a 4 − a 3 2 . [ABSTRACT FROM AUTHOR]

In the present paper, we introduce the notion of generalized ratio- nal contraction including admissible mappings and establish coincidence point and common fixed point results for this class of mappings defined on ordinary as well as ordered metric spaces. Our results extend, generalize and unify com- parable results in the existing literature. Applying these results, we deduce fixed point results on metric spaces endowed with graph. An example and application to obtain the existence of common solution for a system of integral equations are also given in order to illustrate the e¤ectiveness of the o¤ered results. [ABSTRACT FROM AUTHOR]

In the present paper, we introduce the notion of generalized rational contraction including admissible mappings and establish coincidence point and common fixed point results for this class of mappings defined on ordinary as well as ordered metric spaces. Our results extend, generalize and unify com parable results in the existing literature. Applying these results, we deduce fixed point results on metric spaces endowed with graph. An example and application to obtain the existence of common solution for a system of integral equations are also given in order to illustrate the e¤ectiveness of the offered results. [ABSTRACT FROM AUTHOR]

Remarkable feature of contractions is associated with the concept Mizoguchi-Takahashi function. For the purpose of extension and modification of classical ideas related with Mizoguchi-Takahashi contraction, we define generalized Mizoguchi-Takahashi G-contractions and establish some generalized fixed point theorems regarding these contractions in this paper. Some applications to the construction of a fixed point of multivalued mappings in ε-chainable metric space are also discussed. [ABSTRACT FROM AUTHOR]

Common fixed point results for mappings satisfying locally contractive conditions on a closed ball in a 0-complete ordered partial metric space have been established for two, three and four mappings. Instead of monotone mapping, the notion of dominated mappings is applied. We have used weaker contractive conditions and weaker restrictions to obtain unique fixed points. An example is given which shows that how this result can be used when the corresponding results cannot. Our results generalize, extend and improve several well-known conventional results. [ABSTRACT FROM AUTHOR]

We admonish to be careful on studying coupled fixed point theorems since most of the reported fixed point results can be easily derived from the existing corresponding theorems in the literature. In particular, we notice that the recent paper [Semwal and Dimri (2014)] has gaps and the announced result is false. The authors claimed that their result generalized the main result in [Đoric and Lazović (2011)] but, in fact, the contrary case is true. Finally, we present a fixed point theorem for Suzuki type (α, r)-admissible contractions. [ABSTRACT FROM AUTHOR]

We introduce a new iterative scheme called Jungck-CR iterative scheme and study the stability and strong convergence of this iterative scheme for a pair of nonself-mappings using a certain contractive condition. Also, convergence speed comparison and applications of Jungck-type iterative schemes will be shown through examples. [ABSTRACT FROM AUTHOR]

In this paper, we establish some results regarding the existence of the solution to variational inequality, optimization problem and elliptic boundary value problem in Hilbert spaces. Our strategy consists in establishing new best proximity point results in the metric spaces by introducing the concept of cyclic orbital simulative contractions. We also provide nontrivial examples to show that our results are proper generalization. Further, we improve the recent best proximity results for mappings satisfying proximal simulative conditions due to Abbas et al. (2017), Samet (2015), and Tchier et al. (2016) via new class of simulation functions. Our results unify, extend and generalize various existing results. [ABSTRACT FROM AUTHOR]

The MnO2-based heterogeneous catalyst has been considered as one of the most efficient catalysts for enzyme-like catalysis, however, it usually suffers from low stability and difficulty in recycling and reuse. Herein, MnO2 nanosheets supported on nickel foam (NF@MnO2) have been fabricated, via a facile one-step hydrothermal process, as an artificial oxidase for the detection and quantification of ascorbic acid (AA). NF, as a magnetic support, possesses a three-dimensional (3D) skeleton and excellent conductivity, which greatly facilitate the utilization of active sites, electron transfer, as well as separation from the solution with an external magnet. Owing to this unique architecture and the synergistic effect between NF and MnO2, the designed NF@MnO2 composites show enhanced enzyme-like activity toward the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) as compared to NF or MnO2 alone. By virtue of the reducing ability of ascorbic acid (AA), the AA selectively inhibited this reaction with a detection limit of 0.1 μM. More importantly, this kind of NF-based design can be easily extended to the synthesis of other functional materials for enzyme-like catalytic applications. [ABSTRACT FROM AUTHOR]

Conversion‐type transition metal oxide MoO3 has attracted considerable interest as a promising anode material for lithium ion batteries (LIBs), but it suffers from the low electronic conductivity and the large volume changes upon lithiation/delithiation. To overcome these drawbacks, we herein report the full encapsulation of core‐shelled MoO3‐TiO2 into the carbon nanofibers (CNFs) via a facile coaxial electrospinning followed by a two‐step annealing process. TiO2 shells and MoO3 cores were coaxially integrated into the porous CNFs (denote the composite as TiO2/MoO3@CNFs). The two‐step annealing strategy (carbonization in Ar and then oxidization in air) allows the readily encapsulation of MoO3 into CNFs. When applied as anode materials for LIBs, the coaxial TiO2/MoO3@CNFs demonstrate superior lithium storage performance, delivering a high reversible capacity of 561 mAh/g after 300 cycles at 1000 mA/g with a much higher capacity retention of 70.8% than that of the MoO3@CNFs without TiO2 layers (only 42.3%). The results clearly demonstrate that the CNFs matrices and the TiO2 shells together efficiently enhance the electrode conductivity and buffer the volume changes of MoO3 upon cycling. [ABSTRACT FROM AUTHOR]

The encapsulation of small non-noble metal nanoparticles (NPs) within an inorganic layer has received considerable attention owing to their enhanced stability and high catalytic activity. Using a combination of emulsion-free polymerization, inner RF-Ni2+ and outer SiO2 coating, and subsequent carbonization treatment, herein, we have fabricated worm-like structured Ni-based composites in which a high density of nickel NPs are embedded in a carbon layer and also entrapped by SiO2 nanocages. We find that the carbonization temperature plays a vital role in adjusting the size of the Ni NPs. A detailed examination of the encapsulated nickel particles synthesized at 700 °C exhibited the best performance on the catalysis of the reduction of 4-NPs. Moreover, owing to the good alloying ability of the Ni NPs with noble metal NPs, the Ni–Pd alloy NPs are also entrapped in the SiO2 nanocages, which exhibit better performance on the catalysis than the Ni-based composites. The encapsulation of Ni–Pd alloys within SiO2 nanocages also improves stability against agglomeration and metal separation during catalytic operation. [ABSTRACT FROM AUTHOR]

In this paper, we introduce spherical fuzzy sets (SFSs) which is an advanced tool of the fuzzy sets, intuitionistic fuzzy sets and picture fuzzy sets. We investigate the basic properties of SFSs and compare the idea SFSs with picture fuzzy sets. The spaces of spherical membership grades and picture membership grades are examined by graphically. Some useful operation such as spherical fuzzy t'-norms and spherical fuzzy t'-conorms are introduced. Also introduced spherical fuzzy negator and some classifications of spherical fuzzy t'-norms and spherical fuzzy t′-conorms which are useful for development the aggregation operator to aggregate the spherical fuzzy information. Finally, a food circulation center evaluation problem is given as a practical application to demonstrate the usage and applicability of the proposed ranking approach. [ABSTRACT FROM AUTHOR]

The aim of this paper is to introduce α-generalized multi-valued contractions in cone metric spaces over Banach Algebras with solid cones and show the existence of fixed points of these contractions in this context. Our results generalize and extend several known results in metric and cone metric spaces given by some authors. Also, we give one example to illustrate significance of the main result in this paper. [ABSTRACT FROM AUTHOR]

Formulation of uncertainty Volterra integrodifferential equations (VIDEs) is very important issue in applied sciences and engineering; whilst the natural way to model such dynamical systems is to use the fuzzy approach. In this work, we present and prove the existence and uniqueness of four solutions of fuzzy VIDEs based on the Hausdorff distance under the assumption of strongly generalized differentiability for the fuzzy-valued mappings of a real variable whose values are normal, convex, upper semicontinuous, and compactly supported fuzzy sets in . In addition to that, we utilize and prove the characterization theorem for solutions of fuzzy VIDEs which allow us to translate a fuzzy VIDE into a system of crisp equations. The proof methodology is based on the assumption of the generalized Lipchitz property for each nonlinear term appears in the fuzzy equation subject to the specific metric used, while the main tools employed in the analysis are founded on the applications of the Banach fixed point theorem and a certain integral inequality with explicit estimate. An efficient computational algorithm is provided to guarantee the procedure and to confirm the performance of the proposed approach. [ABSTRACT FROM AUTHOR]

Formulation of uncertainty Volterra integrodifferential equations (VIDEs) is very important issue in applied sciences and engineering; whilst the natural way to model such dynamical systems is to use the fuzzy approach. In this work, we present and prove the existence and uniqueness of four solutions of fuzzy VIDEs based on the Hausdorff distance under the assumption of strongly generalized differentiability for the fuzzy-valued mappings of a real variable whose values are normal, convex, upper semicontinuous, and compactly supported fuzzy sets in l . In addition to that, we utilize and prove the characterization theorem for solutions of fuzzy VIDEs which allow us to translate a fuzzy VIDE into a system of crisp equations. The proof methodology is based on the assumption of the generalized Lipchitz property for each nonlinear term appears in the fuzzy equation subject to the specific metric used, while the main tools employed in the analysis are founded on the applications of the Banach fixed point theorem and a certain integral inequality with explicit estimate. An efficient computational algorithm is provided to guarantee the procedure and to confirm the performance of the proposed approach. [ABSTRACT FROM AUTHOR]

An analysis has been carried out for the three dimensional flow of viscous nanofluid in the presence of partial slip and thermal radiation effects. The flow is induced by a permeable stretching surface. Water is treated as a base fluid and alumina as a nanoparticle. Fluid is electrically conducting in the presence of applied magnetic field. Entire different concept of nonlinear thermal radiation is utilized in the heat transfer process. Different from the previous literature, the nonlinear system for temperature distribution is solved and analyzed. Appropriate transformations reduce the nonlinear partial differential system to ordinary differential system. Convergent series solutions are computed for the velocity and temperature. Effects of different parameters on the velocity, temperature, skin friction coefficient and Nusselt number are computed and examined. It is concluded that heat transfer rate increases when temperature and radiation parameters are increased. [ABSTRACT FROM AUTHOR]

Existence and uniqueness theorem are the tool which makes it possible for us to conclude that there exists only one solution to a given problem which satisfies a constraint condition. How does it work? Why is it the case? We believe it, but it would be interesting to see the main ideas behind this. To this end, in this paper, we investigate existence, uniqueness, and other properties of solutions of a certain nonlinear fuzzy Volterra integrodifferential equation under strongly generalized differentiability. The main tools employed in the analysis are based on the applications of the Banach fixed point theorem and a certain integral inequality with explicit estimate. Also, some results for characterizing solution by an equivalent system of crisp Volterra integrodifferential equations are presented. In this way, a new direction for the methods of analytic and approximate solutions is proposed. [ABSTRACT FROM AUTHOR]

Herein, we introduce a stepwise method to construct multi-element PANI@MoS 2 @Fe 3 O 4 /Ag, Au, Pd composites as catalysts, which exhibit excellent performance in the reduction of 4-nitrophenol as well as enzyme-like catalysis. • The PANI@MoS 2 microtubes was synthesized through a self-sacrifice template method. • Fe 3 O 4 and noble metal nanoparticles were covered on the PANI@MoS 2 microtubes. • PANI@MoS 2 @Fe 3 O 4 /Pd exhibited excellent performance in catalytic application. Heterostructures exhibit excellent performance in catalytic application owing to the synergistic effect of multi-components and unique interface structure. Herein, we develop a facile method to construct multi-element PANI@MoS 2 @Fe 3 O 4 /Ag, Au, Pd composites as catalysts, where polyaniline(PANI) microtubes acts as intimal "core", wrinkled ultrathin MoS 2 nanosheets as the outer "shell", tiny Fe 3 O 4 , Ag, Au, Pd nanoparticles(NPs) as the seeds decorated on the outer MoS 2 shell. Benefiting from the synergistic effects among PANI@MoS 2 , Fe 3 O 4 , the noble metal component as well as the unique structure, PANI@MoS 2 @Fe 3 O 4 /Ag, Au, Pd composites show excellent activity in reducing 4-nitrophenol in the presence of NaBH 4 and catalyzing the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) with the participation of H 2 O 2. Furthermore, the PANI@MoS 2 @Fe 3 O 4 /Ag, Au, Pd composites can be easily recycled with the help of magnet. Remarkably, the introduction of MoS 2 on PANI microtubes enhance the electron transfer, reduce the impedance and thus improve the dispersion of the Fe 3 O 4 and noble metals NPs. Our work offers an advanced surface engineering solution to construct a peroxidase-like and 4-nitrophenol catalyst, with bright future in environmental science and biological technology. [ABSTRACT FROM AUTHOR]

Herein, we proposed a facile method to grow hydrophilic Fe 3 O 4 NPs on non-pretreated CFs using a polyol-assisted hydrothermal method, which played a vital role in constructing CFs@Fe 3 O 4 @SiO 2 -C/Ni composites. Benefiting from high coverage of Ni NPs, the unique cloth structure, and magnetic property, they exhibited excellent performance in catalysis on 4-nitrophenol. • Hydrophobic CFs can be converted to hydrophilic magnetic CFs by a simple polyol-assisted hydrothermal method. • A silica layer can be easily coated on magnetic CFs owing to the hydrophilic property of the magnetic CFs. • CFs@Fe 3 O 4 @SiO 2 -C/Ni hybrids are easy to collect and recycle due to their unique structure and good magnetic property. Grafting functional components onto carbon fibers is important for designing many multifunctional composites. However, this process is often hindered by the low reactivity of carbon fibers. Hence, developing innovative grafting strategies with functional groups or nanomaterials on carbon fibers (CFs) is highly desired. Herein, we proposed a facile method to grow hydrophilic Fe 3 O 4 NPs on non-pretreated CFs using a polyol-assisted hydrothermal method, changing hydrophobic CFs to hydrophilic. Benefiting from the hydrophilic property of CFs@Fe 3 O 4 , the resultant CFs@Fe 3 O 4 can be successfully coated by SiO 2 layer to form CFs@Fe 3 O 4 @SiO 2 composites. After a hydrothermal reaction with nickel ions, the CFs@Fe 3 O 4 @nickel silicate composites were fabricated. Followed by coating polydopamine (PDA) layer and then carbonizing in N 2 atmosphere, CFs@Fe 3 O 4 @SiO 2 -C/Ni hybrids can be finally obtained. Notably, the hydrophilic Fe 3 O 4 NPs play a crucial role in the fabrication process, not only improving the interfacial adhesion of carbon fibers for further modification but also providing the main magnetism resource. Moreover, the density and size of Ni NPs can be tailored by tuning pyrolysis temperature. Experimental results confirm that CFs@Fe 3 O 4 @SiO 2 -C/Ni hybrids synthesized at 700 °C gave the best activity on the reduction in 4-nitrophenol, which are easy to collect and recycle due to their unique structure and good magnetic property. [ABSTRACT FROM AUTHOR]