Highly synergistic actuated artificial muscle fiber pair, methods of actuation, and applications

Abstract

The application provides a high-efficiency synergic driving artificial muscle fiber pair, a driving method and application thereof. The artificial muscle fiber pair comprises an artificial muscle fiber as a working electrode, an artificial muscle fiber as a counter electrode and an organic electrolyte; the material and structural parameters of the two artificial muscle fibers are consistent; and the electrolyte is selected from a salt composed of a full alkyl ammonium cation and a perfluoroboric acid anion and / or a perfluorophosphoric acid anion. The application uses the anion-cation salt with symmetric driving properties as the electrolyte, uses two artificial muscle fibers with consistent material parameters as the positive electrode and the negative electrode, and uses the synchronous driving electrochemical fiber pair system, so that the synchronous contraction is realized under the positive and negative potentials, the positive and negative electrodes are active working units in the whole driving cycle, the problem of "counter electrode idling" is completely overcome, the overall output work and energy conversion efficiency are greatly improved, the driving asynchronization or mechanical stress accumulation is effectively avoided, and the cycle stability and response consistency are improved.

Description

Technical Field

[0001] This invention belongs to the field of artificial muscle technology, specifically relating to a pair of artificial muscle fibers that are driven in a highly efficient and coordinated manner, their driving method, and their applications. Background Technology

[0002] In nature, biological muscles drive myofibrils to slide through ATP hydrolysis, achieving a highly efficient, long-range, and reversible contraction-relaxation cycle with an energy conversion efficiency exceeding 20%. Inspired by this, artificial muscle fibers, as a smart material capable of converting external stimuli (such as electricity, heat, light, and chemical energy) into mechanical work, have attracted widespread attention in recent years. Compared to traditional rigid actuators, artificial muscle fibers offer advantages such as flexibility, woven integration, and structural-functional integration, making them particularly suitable for applications such as microrobots, bionic prostheses, and flexible exoskeletons. Based on different driving mechanisms, artificial muscle fibers can be categorized into thermally driven, solvent-driven, and electrochemically driven types. Among them, electrochemical artificial muscle fibers induce volume changes through the reversible insertion / extraction of ions in electrode materials, thereby generating mechanical deformation. This driving method has significant advantages such as low driving voltage, and its energy conversion efficiency is not limited by the Carnot cycle, demonstrating its potential for practical application.

[0003] In recent years, significant progress has been made in the research of electrochemical ionic artificial muscle fibers. Lee et al. constructed helical carbon nanotube artificial muscle fibers using a twisting process, achieving a contractile strain as high as 16.5% in an organic electrolyte (TBA·PF6 / PC), along with a mechanical output work of 1.12 J / g and an energy conversion efficiency of 5.4%. To further improve the driving performance of artificial muscle fibers, Zhang et al. developed a method for preparing large-pitch artificial muscle fiber structures without a mandrel. This method increased the driving capacity of carbon nanotube artificial muscle fibers to 21%, but the contractile work was only 0.052 J / g. Wang et al. reported a process combining electrochemical swelling with high-temperature tension annealing (ITAP) to prepare fibers with a high helical index. This fiber further increased the driving capacity to 47.8% and achieved a contractile work of 2.6 J / g in EMIBF4 / PC solution. To further improve the effective work capacity of artificial muscle fibers, Kim et al. twisted nine single-strand carbon nanotube fibers into a single helical artificial muscle fiber using a twisting method, achieving a drive efficiency of 15.1% and an output work of 3.78 J / g. However, for practical applications, the energy conversion efficiency and output work of electrochemical artificial muscle fibers remain relatively low.

[0004] Current electrochemical artificial muscle fiber actuation processes require the assistance of a counter electrode. During voltage application, cations and anions are injected into the artificial muscle fiber and the counter electrode, respectively. The counter electrode only serves to balance the charge; the ion implantation and efflux processes do not involve volume deformation and do not contribute to external work. This structure, where "artificial muscle fibers dominate contraction and the counter electrode assists in charge balancing," results in nearly half of the input electrical energy being wasted, severely limiting overall energy utilization efficiency. Hyeon et al. successfully utilized the wasted electrical energy on the counter electrode in the dual-electrode system through a dual-fiber structure design and tension optimization (TOP) process, achieving a contraction work of 6.1 J / g at 8.5% drive. Utilizing the ion implantation energy of the counter electrode to convert it into mechanical energy holds promise for improving the energy utilization rate and mechanical output work of artificial muscle fiber systems.

[0005] Developing artificial muscle fiber pairs with dual active contraction is an effective direction for improving performance such as driving efficiency and output power. However, due to differences in size, valence number, migration rate, solvation degree and kinetics during electrode injection, the insertion of anions and cations can cause contraction mismatch between the two artificial muscle fiber pairs, resulting in mechanical damage and structural failure, which will seriously affect their subsequent applications. Summary of the Invention

[0006] The main objective of this invention is to provide a highly efficient synergistically driven artificial muscle fiber pair, its driving method, and its application, in order to overcome the shortcomings of the prior art.

[0007] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a pair of artificial muscle fibers that are highly efficient and synergistically driven, comprising an artificial muscle fiber as a working electrode, an artificial muscle fiber as a counter electrode, and an organic electrolyte, wherein the artificial muscle fiber as the working electrode, the artificial muscle fiber as the counter electrode, and the organic electrolyte constitute an electrochemical system. The artificial muscle fibers serving as the working electrode and the artificial muscle fibers serving as the counter electrode are made of the same material and have the same structural parameters. The electrolyte in the organic electrolyte is selected from a salt composed of peralkylammonium cations, perfluoroboric acid anions, and / or perfluorophosphate anions.

[0008] Secondly, the present invention also provides a method for driving the above-mentioned artificial muscle fiber pair, comprising: Positive and negative voltages are applied to the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode, respectively, so that the anions and cations in the organic electrolyte enter the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode, respectively, so that the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode contract synchronously. Remove the applied voltage to allow the artificial muscle fibers serving as the working electrode and the artificial muscle fibers serving as the counter electrode to relax synchronously.

[0009] Thirdly, the present invention also provides the application of the above-mentioned artificial muscle fiber pairs in the manufacture of microrobots, bionic prostheses, and flexible exoskeletons.

[0010] Compared with the prior art, the beneficial effects of the present invention include at least the following: The artificial muscle fiber pair provided by this invention uses preferred cation and anion salts with symmetrical driving properties as electrolytes, and employs two twisted artificial muscle fibers with identical material parameters as the positive and negative electrodes, respectively, in a synchronously driven electrochemical fiber pair system. This allows the two artificial muscle fibers to contract synchronously under positive and negative potentials, making both the positive and negative electrodes active work units throughout the entire driving cycle. This completely overcomes the problem of "idle counter electrode" in traditional single-electrode systems, significantly improving the overall output power and energy conversion efficiency. At the same time, it ensures that the insertion / extraction rate and volume change response of cations and anions in the artificial muscle fibers are highly consistent, effectively avoiding driving asynchrony or mechanical stress accumulation caused by ion mismatch, and improving cycle stability and response consistency.

[0011] Furthermore, the artificial muscle fiber pair provided by this invention uses two identical artificial muscle fibers matched with an electrolyte having symmetrical driving behavior, which easily achieves consistency in positive and negative electrode driving, has a simple process, can be mass-produced, and can be commercialized.

[0012] The above description is merely an overview of the technical solution of the present invention. In order to enable those skilled in the art to better understand the technical means of this application and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described below in conjunction with detailed drawings. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the structure of a testing device for artificial muscle fiber pairs provided in a typical embodiment of the present invention; Figure 2 This is a test diagram of the driving quantity of artificial muscle fiber pairs under square wave voltage (5.5-0.1 V) charging and discharging, provided in a typical embodiment of the present invention. Figure 3This is a test diagram of the CV curve and corresponding driving curve of the artificial muscle fiber pair at -2.5 to 2.5 V provided in a typical embodiment of the present invention; Figure 4 This is a test chart of the output work and energy conversion efficiency of artificial muscle fibers under different loads provided in a typical embodiment of the present invention; Figure 5 This is a comparative test chart of the output work and energy conversion efficiency of dual / single artificial muscle fibers provided in a typical embodiment of the present invention. Detailed Implementation

[0015] The existing technologies described above mainly suffer from the following drawbacks: 1) Low energy utilization: Traditional electrochemical artificial muscles mostly adopt a single-electrode drive structure, where only the working electrode produces effective mechanical deformation, and the counter electrode is only used for charge balance without doing work, resulting in low overall output power and energy conversion efficiency. 2) Drive asynchrony and kinetic mismatch: In a two-electrode system, if the size or migration rate of the anions and cations is mismatched (e.g., using EMIm), + / PF6 - EMIm + / BF4 - The presence of asymmetric ion pairs can lead to asynchronous insertion / extraction behaviors of the positive and negative electrodes. This is especially true in solid-state / gel devices, where mechanical coupling amplifies this asymmetry, reducing driving efficiency and cycle stability.

[0016] In view of the shortcomings of the prior art, the inventors of this invention, through long-term research and extensive practice, believe that screening organic electrolyte systems with compatible anions and cations is an effective way to achieve efficient actuation of electrochemical artificial muscle fibers, and thus proposed the technical solution of this invention. The following will further explain and illustrate this technical solution, its implementation process, and its principles.

[0017] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0018] This invention first provides a pair of highly efficient synergistically driven artificial muscle fibers, comprising an artificial muscle fiber as a working electrode, an artificial muscle fiber as a counter electrode, and an organic electrolyte. The artificial muscle fiber as the working electrode, the artificial muscle fiber as the counter electrode, and the organic electrolyte constitute an electrochemical system. The artificial muscle fiber as the working electrode and the artificial muscle fiber as the counter electrode have the same material and structural parameters. The electrolyte in the organic electrolyte is selected from a salt composed of peralkylammonium cations, perfluoroborate anions, and / or perfluorophosphate anions.

[0019] In some implementation schemes, carbon fiber is relatively easy to achieve symmetrical synchronous driving of anions and cations. That is, the artificial muscle fiber used as the working electrode and the artificial muscle fiber used as the counter electrode are made of any one or more of carbon nanotube fibers, carbon fibers, graphene fibers, graphite fibers, or composite fibers of any one or more of them with polymer materials.

[0020] In some embodiments, the all-alkylammonium cation has 2-4 carbon atoms in its alkyl chain. The appropriate number of carbon atoms determines the size of the ion, its rate of movement in the solvent, and its rate of embedding into artificial muscle fibers; therefore, the number of carbon atoms in the alkyl chain needs to be limited to meet the requirements of symmetry-driven operation.

[0021] Specifically, in some embodiments, the electrolyte includes any one or a combination of two or more of tetraethylammonium hexafluorophosphate, tetrabutylammonium hexafluorophosphate, tetraethylammonium tetrafluoroborate, and tetrabutylammonium tetrafluoroborate.

[0022] Furthermore, in some embodiments, the concentration of the electrolyte in the organic electrolyte is 0.1-5 mol / L.

[0023] In some embodiments, the solvent in the organic electrolyte includes propylene carbonate, ethylene carbonate, acetonitrile, and dimethyl sulfoxide.

[0024] In some embodiments, both the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode are in a twisted state.

[0025] In some embodiments, the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode have a diameter of 50-500 μm, a pitch of 50-500 μm, and a twist of 9000-15000 turns / m.

[0026] In some implementations, the driving behaviors of the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode are mechanically coupled. Mechanical coupling means that the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode need to contract or relax synchronously in the driving system. The simplest example is that the ends of both the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode are fixed to the same anchor, requiring synchronous force application and similar contraction values ​​to distribute stress evenly. Alternatively, various encapsulation methods in the prior art can be used, such as using gels or polymer membranes to encapsulate two artificial muscle fibers into a single solid or gel-like composite fiber (existing technologies include encapsulating the working electrode and counter electrode to form a single composite fiber), allowing synchronous contraction or relaxation. In this case, the aforementioned "organic electrolyte" is not entirely liquid; it may be in a gel state, such as a gel containing the aforementioned electrolyte, or an electrolyte adsorbed in a porous material, etc.

[0027] As a typical embodiment of the above technical solution, and addressing the aforementioned challenges, a preferred embodiment of the present invention proposes a novel dual-active contraction artificial muscle fiber driving strategy: using salts with symmetrical ion intercalation behavior, such as tetraethylammonium hexafluorophosphate (TEA·PF6), as electrolytes, dissolved in organic solvents such as propylene carbonate (PC), to construct a symmetrical electrochemical artificial muscle fiber pair system. The key to this system lies in TEA… + With PF6 - With excellent ion compatibility, it synchronously inserts / extracts from the negative and positive electrodes during charging and discharging, driving the two carbon nanotube fibers to achieve equal-speed and equal-volume contraction. As a result, both the positive and negative electrodes are active work units in their respective half-cycles, completely eliminating the inefficient mode of "idle counter electrode" in the traditional way, and realizing full-cycle bidirectional drive with high synchronicity and high energy utilization.

[0028] To achieve actuation, embodiments of the present invention also provide a method for actuating the artificial muscle fiber pair provided in any of the above embodiments, comprising: Positive and negative voltages are applied to the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode, respectively, so that anions and cations in the electrolyte enter the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode, respectively, so that the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode contract synchronously. Remove the applied voltage to allow the artificial muscle fibers serving as the working electrode and the artificial muscle fibers serving as the counter electrode to relax synchronously.

[0029] It should be noted that in the above driving method, the relevant driving parameters, such as load, driving voltage, etc., vary with the thickness and material of the artificial muscle fibers, as well as the concentration and type of organic electrolyte. They are not limited to a fixed parameter range, nor are they limited to the scope of the limited embodiments described in this invention. Depending on the circumstances, those skilled in the art are able to determine the optimal driving parameters through conditional experiments and meet the requirements of symmetrical synchronous driving.

[0030] This invention also provides the application of the artificial muscle fiber pairs provided in any of the above embodiments in the fabrication of microrobots, bionic prostheses, and flexible exoskeletons.

[0031] The technical solution of the present invention will be further described in detail below through several embodiments and in conjunction with the accompanying drawings. However, the selected embodiments are only for illustrating the present invention and do not limit the scope of the present invention.

[0032] Example 1 This embodiment illustrates the construction process and driving performance test of a highly efficient collaboratively driven artificial muscle fiber pair system, as detailed below.

[0033] 1) Preparation method, mainly including the following steps: Step 1: Preparation of artificial muscle fibers First, the carbon nanotube fibers are twisted. The specific steps are as follows: one end of the carbon nanotube fiber is vertically suspended on a twisting motor, and the other end is suspended with a certain weight (1-10g is acceptable). The fiber is twisted at a certain speed until a helical structure is formed, with a fiber diameter of 180μm, a pitch of 200μm, and a twist of 12000 turns / m.

[0034] Step 2: Construction of the test system Tetraethylhexafluorophosphate ammonium was added to propylene carbonate at a concentration of 0.5 mol / L to obtain a tetraethylhexafluorophosphate ammonium propylene carbonate solution. Then, a twisted carbon nanotube fiber electrode was used as the positive electrode, and a carbon nanotube fiber electrode of the same length was used as the negative electrode to construct a synchronously driven electrochemical fiber pair system, the structure of which is shown below. Figure 1 As shown.

[0035] Figure 2 This is the driving curve of the aforementioned artificial muscle fibers under a square wave voltage. At 5.5 V (0–8 s), both types of ions induce fiber contraction, and the driving force gradually increases. (TEA) + The driving force for cation generation is 35.66%, PF6 -The driving force of anion generation was 35.91%; at a voltage of -0.1 V (8–16 s), the driving force rapidly dropped back to near zero; both exhibited good reversibility and fast response capability, and demonstrated excellent symmetric driving characteristics.

[0036] Figure 3 The voltage-current curves and corresponding driving curves from -2.5 V to 2.5 V during three-electrode CV testing are shown. From the open-circuit potential to 2.5 V, hexafluorophosphate anions can effectively embed into the fiber, inducing significant expansion and contraction; from -1 V to -2.5 V, tetraethylammonium cations can embed into the fiber, producing deformation of the same magnitude. The maximum driving force of the fiber is 18.10% under positive voltage and 17.68% under negative voltage. Significant contraction deformation occurs under both positive and negative voltages, and the values ​​are similar, indicating that the fiber is a dual-electrode synergistic driving type—that is, both the positive and negative electrodes can actively perform work, verifying the effectiveness of the "dual-fiber symmetrical structure" of this invention. The driving curves are "butterfly-shaped" with no obvious hysteresis, indicating low internal resistance and good kinetics.

[0037] Figure 4 This represents the output work and energy conversion efficiency of the artificial muscle fiber pair under different loads. As the load increases, the system's output work and energy conversion efficiency show an upward trend. Under a load of 24.5 g, the system's output work reaches a maximum of 5.34 J / g, and the energy conversion efficiency reaches a maximum of 0.7156%.

[0038] Figure 5 This study compares the work output and energy conversion efficiency of dual / single-fiber artificial muscle fibers (with the counter electrode replaced by a graphite electrode) under the same electrolyte system. It can be observed that the work output of the dual-fiber system is twice that of the single-fiber system, while the efficiency of the dual-fiber system is nearly three times that of the single-fiber system. This indicates that under the same voltage input, the dual-fiber system can convert electrical energy into mechanical energy more efficiently, and the overall driving capability of the system is also stronger.

[0039] Example 2 This embodiment is largely the same as Embodiment 1, with the main difference being the different manufacturing process of the artificial muscle fiber pair, as detailed below.

[0040] Step 1: Fabrication of fiber electrodes One end of the graphene fiber is vertically suspended on a twisting motor, and the other end is suspended with a certain weight (1-10g). The fiber is twisted at a certain speed until a spiral structure is formed. The fiber diameter is 200μm, the pitch is 240μm, and the twist is 11000 turns / m.

[0041] Step 2: Construction of the test system Tetraethylhexafluorophosphate was added to propylene carbonate to obtain a tetraethylhexafluorophosphate propylene carbonate solution with a concentration of 0.5 mol / L. Then, a twisted graphene fiber electrode was used as the positive electrode, and a graphene fiber electrode of the same length was used as the negative electrode to construct a synchronously driven electrochemical fiber pair system.

[0042] Example 3 This embodiment is largely the same as Embodiment 1, with the main difference being the different manufacturing process of the artificial muscle fiber pair, as detailed below.

[0043] Step 1: Fabrication of fiber electrodes One end of the graphite fiber is vertically suspended on a twisting motor, and the other end is suspended with a certain weight (1-10g). The fiber is twisted at a certain speed until a spiral structure is formed. The fiber diameter is 220μm, the pitch is 260μm, and the twist is 10500 turns / m.

[0044] Step 2: Construction of the test system Tetraethyl hexafluorophosphate was added to propylene carbonate to obtain a tetraethyl hexafluorophosphate propylene carbonate solution with a concentration of 0.5 mol / L. Then, a twisted graphite fiber electrode was used as the positive electrode, and a graphite fiber electrode of the same length was used as the negative electrode to construct a synchronously driven electrochemical fiber pair system.

[0045] Example 4 This embodiment is largely the same as Embodiment 1, with the main difference being the different manufacturing process of the artificial muscle fiber pair, as detailed below.

[0046] Step 1: Fabrication of fiber electrodes One end of the carbon fiber is vertically suspended on a twisting motor, and the other end is suspended with a certain weight (1-10g). The fiber is twisted at a certain speed until a spiral structure is formed with a diameter of 160μm, a pitch of 180μm, and a twist of 13000 turns / m.

[0047] Step 2: Construction of the test system Tetraethylhexafluorophosphate was added to propylene carbonate to obtain a tetraethylhexafluorophosphate propylene carbonate solution with a concentration of 0.5 mol / L. Then, a twisted carbon fiber electrode was used as the positive electrode, and a carbon fiber electrode of the same length was used as the negative electrode to construct a synchronously driven electrochemical fiber pair system.

[0048] Example 5 This embodiment is largely the same as Embodiment 1, with the main difference being the different manufacturing process of the artificial muscle fiber pair, as detailed below.

[0049] Step 1: Fabrication of fiber electrodes One end of a carbon nanotube-coated nylon fiber is vertically suspended on a twisting motor, and the other end is suspended with a certain weight (1-10g). The fiber is twisted at a certain speed until a spiral structure is formed with a diameter of 250μm, a pitch of 300μm, and a twist of 10000 turns / m.

[0050] Step 2: Construction of the test system Tetraethylhexafluorophosphate was added to propylene carbonate to obtain a tetraethylhexafluorophosphate propylene carbonate solution with a concentration of 0.5 mol / L. Then, a twisted carbon nanotube-coated nylon fiber electrode was used as the positive electrode, and a carbon nanotube-coated nylon fiber electrode of the same length was used as the negative electrode to construct a synchronously driven electrochemical fiber pair system.

[0051] Example 6 This embodiment is largely the same as Embodiment 1, with the main difference being the different solutes in the organic electrolyte, as detailed below.

[0052] Step 1: Fabrication of fiber electrodes One end of the carbon nanotube fiber is vertically suspended on a twisting motor, and a certain weight (1-10g) is suspended from the other end. The fiber is twisted at a certain speed until a spiral structure is formed. The fiber diameter is 180μm, the pitch is 200μm, and the twist is 12000 turns / m.

[0053] Step 2: Construction of the test system Tetrabutylammonium hexafluorophosphate was added to propylene carbonate to obtain a tetrabutylammonium hexafluorophosphate propylene carbonate solution with a concentration of 0.5 mol / L. Then, a twisted carbon nanotube fiber electrode was used as the positive electrode, and a carbon nanotube fiber electrode of the same length was used as the negative electrode to construct a synchronously driven electrochemical fiber pair system.

[0054] Example 7 This embodiment is largely the same as Embodiment 1, with the main difference being the different solutes in the organic electrolyte, as detailed below.

[0055] Step 1: Fabrication of fiber electrodes One end of the carbon nanotube fiber is vertically suspended on a twisting motor, and a certain weight (1-10g) is suspended from the other end. The fiber is twisted at a certain speed until a spiral structure is formed. The fiber diameter is 180μm, the pitch is 200μm, and the twist is 12000 turns / m.

[0056] Step 2: Construction of the test system Tetraethyltetrafluoroborate ammonium was added to propylene carbonate to obtain a tetraethyltetrafluoroborate ammonium carbonate propylene carbonate solution with a concentration of 0.1 mol / L. Then, a twisted carbon nanotube fiber electrode was used as the positive electrode, and a carbon nanotube fiber electrode of the same length was used as the negative electrode to construct a synchronously driven electrochemical fiber pair system.

[0057] Example 8 This embodiment is largely the same as Embodiment 1, with the main difference being the different solutes in the organic electrolyte, as detailed below.

[0058] Step 1: Fabrication of fiber electrodes One end of the carbon nanotube fiber is vertically suspended on a twisting motor, and a certain weight (1-10g) is suspended from the other end. The fiber is twisted at a certain speed until a spiral structure is formed. The fiber diameter is 180μm, the pitch is 200μm, and the twist is 12000 turns / m.

[0059] Step 2: Construction of the test system Tetrabutyltetrafluoroborate ammonium was added to propylene carbonate to obtain a tetrabutyltetrafluoroborate ammonium carbonate propylene carbonate solution with a concentration of 5 mol / L. Then, a twisted carbon nanotube fiber electrode was used as the positive electrode, and a carbon nanotube fiber electrode of the same length was used as the negative electrode to construct a synchronously driven electrochemical fiber pair system.

[0060] Similar to Example 1, Examples 2-8 above can all achieve highly symmetrical dual-electrode driving behavior, and the output power and energy conversion efficiency are significantly increased compared with the single-electrode driving structure in the same system, which will not be elaborated further here.

[0061] It should be understood that the above embodiments are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A pair of artificial muscle fibers driven by high efficiency and synergy, characterized in that, The system includes an artificial muscle fiber as a working electrode, an artificial muscle fiber as a counter electrode, and an organic electrolyte, wherein the artificial muscle fiber as a working electrode, the artificial muscle fiber as a counter electrode, and the organic electrolyte constitute an electrochemical system. The artificial muscle fibers serving as the working electrode and the artificial muscle fibers serving as the counter electrode are made of the same material and have the same structural parameters. The electrolyte in the organic electrolyte is selected from a salt composed of peralkylammonium cations, perfluoroboric acid anions, and / or perfluorophosphate anions.

2. The artificial muscle fiber pair according to claim 1, characterized in that, The artificial muscle fibers used as working electrodes and artificial muscle fibers used as counter electrodes are made of any one or more of carbon nanotube fibers, carbon fibers, graphene fibers, and graphite fibers, or composite fibers of any one or more of these fibers with polymer materials.

3. The artificial muscle fiber pair according to claim 1, characterized in that, The alkyl chain of the all-alkylammonium cation has 2-4 carbon atoms.

4. The artificial muscle fiber pair according to claim 3, characterized in that, The electrolyte includes any one or a combination of two or more of tetraethylammonium hexafluorophosphate, tetrabutylammonium hexafluorophosphate, tetraethylammonium tetrafluoroborate, and tetrabutylammonium tetrafluoroborate.

5. The artificial muscle fiber pair according to claim 1, characterized in that, The concentration of the electrolyte in the organic electrolyte solution is 0.1-5 mol / L; And / or, the solvent in the organic electrolyte includes any one or a combination of two or more of propylene carbonate, ethylene carbonate, acetonitrile, and dimethyl sulfoxide.

6. The artificial muscle fiber pair according to claim 1, characterized in that, Both the artificial muscle fiber used as the working electrode and the artificial muscle fiber used as the counter electrode are in a twisted state.

7. The artificial muscle fiber pair according to claim 6, characterized in that, The artificial muscle fibers used as working electrodes and as counter electrodes have diameters of 50-500 μm, pitches of 50-500 μm, and twists of 9000-15000 turns / m.

8. The artificial muscle fiber pair according to claim 1, characterized in that, The artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode are mechanically coupled in terms of their driving behavior.

9. The method for driving the artificial muscle fiber pair according to any one of claims 1-8, characterized in that, include: Positive and negative voltages are applied to the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode, respectively, so that the anions and cations in the organic electrolyte enter the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode, respectively, so that the artificial muscle fiber serving as the working electrode and the artificial muscle fiber serving as the counter electrode contract synchronously. Remove the applied voltage to allow the artificial muscle fibers serving as the working electrode and the artificial muscle fibers serving as the counter electrode to relax synchronously.

10. The application of the artificial muscle fiber pair according to any one of claims 1-8 in the fabrication of microrobots, bionic prostheses, and flexible exoskeletons.

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