Yicen Zhang
Cen Zhang- Department of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang, Hunan, China
Developing efficient and stable non-noble metal catalysts for the electrocatalytic hydrogen evolution reaction (HER) is of great significance. MoS2 has become a promising alternative to replace Pt-based electrocatalysts due to its unique layered structure and adjustable electronic property. However, most of the reported 2H-MoS2 materials are stable, but the catalytic activity is not very ideal. Therefore, a series of strategies such as phase modulation, element doping, defect engineering, and composite modification have been developed to improve the catalytic performance of MoS2 in the HER. Among them, phase engineering of 2H-MoS2 to 1T-MoS2 is considered to be the most effective strategy for regulating electronic properties and increasing active sites. Hence, in this mini-review, the common phase modulation strategies, characterization methods, and application of 1T-MoS2 in the HER were systematically summarized. In addition, some challenges and future directions are also proposed for the design of efficient and stable 1T-MoS2 HER catalysts. We hope this mini-review will be helpful to researchers currently working in or about to enter the field.
Introduction
Hydrogen (H2) is considered a promising renewable energy source because of high energy density and zero pollution (Lee et al., 2021; Zhang L. et al., 2022). Nowadays, H2 is produced on an industrial scale through methane reforming or coal gasification, which inevitably releases a large amount of greenhouse gases (Li et al., 2022a; Li et al., 2022b; Yang et al., 2022). By contrast, the electrochemical hydrogen evolution reaction (HER) from water-splitting is more environmentally friendly because the electricity could be derived from solar energy or wind power (Xiang et al., 2021; Ye et al., 2021; Gong et al., 2022). As the best catalyst for the HER, the high price and low reserves of platinum (Pt) make it unable to meet the needs of industrialization. Hence, developing non-noble metals with abundant reserves and low prices to efficiently catalyze the HER is still challenging.
As a typical two-dimensional material, MoS2 showed great potential to replace Pt theoretically and experimentally (Cao et al., 2021b; Gong et al., 2021; Li X.-Y. et al., 2022). The monolayer of MoS2 is connected by the S–Mo–S covalent bond, where different arrangements of Mo and S layers will result in the formation of different crystal phases, such as 1T, 2H, and 3R. For catalysis, 2H-MoS2 and 1T-MoS2 are most used and compared (Gong et al., 2020; Li et al., 2021; Zhang et al., 2022a). The 2H phase possesses triangular prism coordination with semiconducting properties and is thermodynamically stable. However, the 1T phase possesses octahedral coordination and is a metastable phase with metallic properties (Tang and Jiang, 2015). Due to the different crystal structures, the physicochemical properties of 1T and 2H phases show great differences. The electronic conductivity of metallic 1T-MoS2 is about five orders of magnitude higher than that of 2H-MoS2. In addition, it has active centers on both the basal and edge planes, while 2H-MoS2 only exhibits catalytic activity on the edge planes (Tang and Jiang, 2016). In the past decades, most of the reported MoS2 electrocatalysts are 2H-MoS2 due to the thermodynamic instability of the 1T phase. Hence, phase modulation from 2H to 1T has been achieved by lateral translation of the S plane and changing the filling state of Mo 3d orbitals. Although a series of regulation strategies have been developed in recent years, there are few systematic reviews on the targeted synthesis and HER application of 1T-MoS2. Therefore, we have summarized some common preparation methods, necessary characterization techniques of 1T-MoS2, and its application in the HER (Figure 1). Finally, the challenges for targeted synthesis and rational design of advanced 1T-MoS2 electrocatalysts are also proposed.
FIGURE 1. Schematic summary of phase modulation, characterization techniques, and HER application of 1T-MoS2.
Characterization techniques for 1T-MoS2
Usually, the 1T phase and 2H phase coexist in the as-synthesized MoS2 materials. Therefore, it is necessary to analyze the 1T phase qualitatively and quantitatively, which plays an important role for studying the structure–performance relationship and developing high-performance MoS2-based electrocatalysts. Due to the huge structure difference between 1T-MoS2 and 2H-MoS2, the characterization of 1T-MoS2 could be conducted by X-ray diffraction (XRD), Raman spectroscopy (Raman), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM), and X-ray absorption spectroscopy (XAS).
XRD is frequently utilized to reflect the lattice parameter changes caused by the phase transition from 2H-MoS2 to 1T-MoS2. 1T-MoS2 obtained by phase transition through guest molecule intercalation will increase the interlayer spacing, which is accompanied by a peak downshift at 2θ = 14o, corresponding to the (002) crystal planes of 2H-MoS2. According to the literature reports, the diffraction peak of 1T-MoS2 obtained by NH3 (Liu et al., 2015; Zhang et al., 2022a) and Na+(Wang X. et al., 2014) intercalation shifted from 14o to 9.4o and 12.4o, respectively. This result indicates that the magnitude of the peak shift depends on the size of intercalated molecules or ions. However, it is difficult to observe the characteristic diffraction peak of single- or few-layer 1T-MoS2 obtained by exfoliation due to the weak crystallinity (Tong et al., 2017). In addition, only the diffraction peaks of 2H-MoS2 could be detected when the 1T phase content in 2H/1T-MoS2 is low, and the existence of the 1T phase needs to be further determined by Raman or XPS (Cao et al., 2022).
Raman spectroscopy is a simple and effective technique to determine the existence of 1T-MoS2. Typically, 2H-MoS2 shows two characteristic bands of E1 2g and A1g at 383 and 408 cm−1, respectively (Zhang et al., 2021). However, a set of new bands at 152, 226, and 330 cm−1 appeared with the presence of the 1T phase (Liu Z. et al., 2017). In addition, it is difficult to observe these characteristic peaks sometimes with the low proportion of the 1T phase in the 1T/2H-MoS2 composite, which requires further verification by XPS (Pradhan and Sharma, 2019). Meanwhile, it should be emphasized that the laser power of the Raman test is usually less than 0.1 mW because high laser power could destroy the structure of MoS2 and even burn the sample.
XPS is the only characterization method which could quantitatively analyze the content of the 1T phase. It has been the preferred analysis method for researchers because of its simple operation. According to previous studies, MoS2 exists as a 2H phase with semiconductor properties when the Mo 3d orbitals are fully filled. When the electrons are partially filled, MoS2 is a 1T phase with metallic properties (Voiry et al., 2015). Generally, the binding energies of Mo4+ 3d5/2 and Mo4+ 3d3/2 in 1T-MoS2 are 231.5 and 228.3 eV, respectively, which are 0.9 eV lower than those of 2H-MoS2 (232.4 and 229.2 eV) due to fewer electrons being filled (Wang et al., 2017; Cao et al., 2021a; Zhang et al., 2022b). Additionally, the 1T/2H phase proportion could be easily obtained by peak fitting in the Mo 3d region.
The atomic arrangement of MoS2 could be directly observed by HRTEM to distinguish the crystal phase. As a layered compound, the structure difference between 1T-MoS2 and 2H-MoS2 can be visualized from the top view ([001] plane) and the side view ([100] plane). From the enlarged image on the basal plane, 1T-MoS2 displays a typical triangular configuration with octahedral coordination, while 2H-MoS2 exhibits a honeycomb configuration with trigonal prism coordination (Sun et al., 2018). By observing from the edge plane, the S–Mo–S coordination of 1T-MoS2 shows a chevron configuration, while 2H-MoS2 exhibits a diagonal line pattern (Enyashin et al., 2011). Since it is difficult for operators to select a side view, most literature works adopt the atomic structure of the basal plane to confirm the existence of the 1T phase.
XAS is a newly developed technique for analyzing the structure and phase of MoS2. The phase change between 1T and 2H is detected by observing the signal vibration caused by scattering of incident photoelectrons between two surrounding atoms. Furthermore, the bond length of MoS2 could be determined by Fourier transform of the obtained Mo K-edge spectra (Yang et al., 2017). Deng et al. found that the bond length and peak strength of Mo–Mo and Mo–S bonds in 1T-MoS2 were smaller than those in 2H-MoS2 (Deng et al., 2019). However, characterization and data analysis of XAS require a high cost and rich experience, which makes it a limited technique utilized by researchers.
Phase modulation strategies of 1T-MoS2
Generally, 1T-MoS2 does not exist in nature because of its metastable property. At present, the synthesis strategy in the laboratory is to convert 2H-MoS2 into 1T-MoS2 through phase modulation. So far, some strategies such as ion intercalation, doping, strain regulation, gas treatment, and plasma bombardment have been reported to realize the targeted phase transition successfully.
Since the adjacent layers of MoS2 were connected by the weak van der Waals force so that alkali metals (Li, Na, and K), small inorganic molecules (NH3, H2O (Geng et al., 2017), and RGO (Mahmood et al., 2016)), and organic molecules (alcohol or organic acid) could be inserted into the interlayers easily. During the intercalation process, the electrons of guest species are transferred to the Mo3d orbitals to change the filling state, which results in partial conversion of the originally stable 2H phase into the 1T phase. In addition, the intercalated molecules will be positively charged. Chemical lithium intercalation is the most common and mature intercalation method to obtain 1T-MoS2 (Lukowski et al., 2013; Tan et al., 2018; Xu et al., 2019). Typically, bulk MoS2 powders are immersed into an excess n-butyllithium solution for 6–72 h at room temperature in a glove box. With the assistance of ultrasonication, single- or few-layer 1T-MoS2 nanosheets are obtained. The 1T phase content in the exfoliated MoS2 products is affected by lithium time, solvent, and temperature, and a highest content of the 70% 1T phase could be obtained (Zheng et al., 2014). In a similar procedure, Na+(Gao et al., 2015) and K+(Zhang et al., 2016) could also be intercalated into the interlayer space, thus inducing 2H to 1T phase transition. In order to further increase the 1T content, a liquid-ammonia-assisted lithiation (LAAL) method was developed to greatly enhance the intensity of the lithium process, resulting in monolayer porous MoS2 nanosheets with a 1T content of about 81% (Yin et al., 2016). Considering the disadvantages such as high risk and uncontrollable insertion degree for alkali metal chemical intercalation, electrochemical intercalation has been extensively explored recently. The biggest difference between these two methods is that the driving force of electrochemical intercalation is much larger, thus exhibiting better controllability and higher efficiency (Wang X. et al., 2014; Chen et al., 2018). For example, Chen et al. prepared monolayer MoS2 quantum dots with size of 3–5 nm and 1T phase content of 92–97% by a quasi-full electrochemical process, which was achieved by a greatly increased Li intercalation content (Chen et al., 2018).
Small inorganic molecules such as NH3 are also an appropriate intercalation candidate to trigger phase transition. Usually, if excessive precursors containing -NH2 such as thiourea (Zhang et al., 2022a), thioacetamide (Liu Q. et al., 2017), urea (Sun et al., 2018), or ammonium bicarbonate (Wang et al., 2017) are added in the hydrothermal/solvothermal synthesis of MoS2, some NH3 molecules generated by hydrolysis could be easily inserted into the interlayer to obtain 1T-MoS2. Meanwhile, it should be noted that the hydrothermal temperature needs to be lower than 200 °C because the 1T phase is unstable at high temperatures. As an example, Sun et al. synthesized MoS2 nanosheets with a 1T phase fraction of 16.4%–90.2% by introducing different amounts of urea in the hydrothermal system (Sun et al., 2018). Liu et al. prepared a 1T-MoS2/single-walled carbon nanotube by adding excess thioacetamide to provide intercalated NH4+, which obtained the 1T phase content of around 60% (Liu Q. et al., 2017). However, according to a recent report, metallic 1T-MoS2 obtained by NH4+ was unstable and changed back to 2H-MoS2 spontaneously after exposing in air for 15 days. Thus, the authors developed a two-step solvothermal strategy which adopted organic solvents such as methanol, ethanol, isopropanol, or butanol to treat NH4+-intercalated 1T-MoS2 again. Interestingly, the C2H5OH-intercalated 1T-MoS2 preserved the 1T structure well after being stored in air for 360 days, where the superior stability was attributed to the strong interaction between ethanol and the MoS2 surface (Li et al., 2020). In addition, ascorbic acid (AA) has also been reported as an excellent intercalation molecule to synthesize high stable 1T-MoS2 via a one-step hydrothermal method (Wang et al., 2022).
Doping heteroatoms into the lattice of 2H-MoS2 is considered an efficient way to modulate local electronic properties and induce 2H-to 1T transformation. The doped elements can be metals (Re, Co, Ru, Cu, Pd (Luo et al., 2018), Fe (Zhao et al., 2017), and Ni (Wang et al., 2022)) or non-metals (N and P), and it must be incorporated uniformly at the atomic scale. The doping technique can adopt a one-step method or post-treatment modification method. Considering Re has a close atomic radius of Mo and ReS2 has a similar structure as distorted 1T-MoS2, Xia et al. synthesized Re-doped 1T/2H-MoS2 nanosheets through a hydrothermal and anneal process (Xia et al., 2018). Ji et al. utilized a one-pot solvothermal strategy to prepare single-atom Cu-doped MoS2 nanoflowers with a large fraction of the 1T phase. In the solvothermal procedure, the Cu precursor reacted with MoS3 and donated electrons to MoS2, thus inducing and stabilizing the 1T phase (Ji et al., 2019). Similarly, Co-doped MoS2 nanosheets with a dominant metallic 1T phase were synthesized by doping Co2+ into the basal planes and S-edge planes (Nethravathi et al., 2017). Atomic Ru was incorporated into MoS2 nanosheets (SA-Ru-MoS2) using a simple one-step impregnation method, where Ru substituted lattice Mo atoms and triggered local phase transition (Zhang et al., 2019). Non-metal elements such as nitrogen or phosphorus were also frequently doped into MoS2 to modulate phase transition. Wang et al. embedded P into the lattice of 2H-MoS2 by a simple one-pot annealing method to induce partial phase transition and obtained ultra-stable in-plane 1T-2H/MoS2 heterostructures (Wang et al., 2018). Deng et al. prepared N-doped and PO43--intercalated MoS2 arrays by annealing with NaH2PO4 in NH3 atmosphere (Deng et al., 2019). Both the N doping and PO43- intercalation contributed to the formation of the 1T phase and acted synergistically, which induced about 41% of the 2H phase to 1T phase.
Recently, a strain regulation strategy has been developed to tune the electronic structure and realize the phase modulation of MoS2. Chi et al. reported that 2H to 1T phase transition occurred at an extremely high physical pressure (> 20 GPa) through layer sliding, which was evidenced by Raman spectra and XRD patterns (Chi et al., 2014). Similarly, chemical compressive force caused by bending also can result in gliding of the S plane and phase transition. Hwang et al. adopted N-(2-aminoethyl)-3α-hydroxy-5β-cholan-24-amide as a self-assembling material to roll up the exfoliated 2H-MoS2 nanosheets, which obtained 1T@2H nanoscrolls with a 1T phase content of 58% and high stability after heated at 200 C (Hwang et al., 2017).
Sulfur vacancies (Vs) produced by gas treatment or plasma bombardment could play the role of electron donors to trigger local phase transition. Yang et al. used Ar and O2 to treat monolayer MoS2, which leads to partial formation of the 1T phase by modulating defect configuration (Yang et al., 2016). Meanwhile, it should be pointed out that Vs were formed within the basal plane and at the edge planes by Ar and O2 treatment, respectively, and the 1T phase percentage was higher for O2-treated samples due to a stronger phase-driven force. Zhu et al. reported a facile and controllable Ar bombardment technique to produce single Vs and induce phase transition on monolayer 2H-MoS2 (Zhu et al., 2017). Ar-plasma treatment can effectively trigger the lateral sliding of the top S layer, thus obtaining 1T@2H-MoS2 mosaic structures with a 1T fraction of up to 40%. Although controllable and scalable, these two methods need further improvement because the 1T content in products is usually lower than 50%, which probably resulted from the limited sulfur vacancies formed in the lattice.
HER performance of 1T-MoS2 catalysts
As a promising catalyst in the field of electrochemical hydrogen evolution, 1T-MoS2 has attracted much attention in recent years. Wang et al. prepared 1T/2H-MoS2 through NH4+-intercalation, which showed an excellent HER performance with a low overpotential of 234 mV at a current density of 10 mA/cm2 (η10) and a small Tafel slope of 46 mV dec-1 due to the enhanced conductivity and activated basal planes (Wang et al., 2017). As a comparison, the 2H-MoS2 had a much higher η10 of 309 mV and a larger Tafel slope of 89 mV dec−1. Lukowski et al. reported a greatly improved HER activity of metallic 1T-MoS2 nanosheets with a η10 of 187 mV and a Tafel slope of 43 mV dec−1 (2H-MoS2 with a η10 of 320 mV and a Tafel slope of 110 mV dec−1) prepared by chemical lithium intercalation, which was attributed to the fast electrode kinetics and proliferated density of catalytic active sites (Lukowski et al., 2013). Furthermore, porous MoS2 nanosheets with a dominant phase of 1T and a large number of edges and sulfur vacancies prepared by a facile LAAL strategy exhibited the best HER activity (a η10 of 153 mV and a Tafel slope of 43 mV dec−1) until now for the bare MoS2 catalysts (Yin et al., 2016).
Elemental doping is an effective route to regulate the d-band structure and hydrogen adsorption free energy (ΔGH), thus further improving the HER activity of 1T-MoS2. Recently, the inert basal plane of 2H-MoS2 was activated by atomic Pd doping through a spontaneous interfacial redox method. Structural characterization revealed that Pd substituted the Mo sites and produced sulfur vacancies at the same time, thus converting the partial 2H phase into the stabilized 1T phase (Luo et al., 2018). Theoretical calculation results indicated a ΔGH of -0.02 eV at the sulfur sites of neighboring Pd atoms, which is highly active for the HER. Finally, an optimized Pd-MoS2 catalyst with 1.0 wt% Pd doping had a small η10 of 78 mV and an excellent stability after 5,000 cycles, which is much better than that of pristine 2H-MoS2 with a η10 of 328 mV and a Tafel slope of 157 mV dec−1. Qi et al. reported a single-atom Co doped distorted 1T-MoS2 nanosheet (SA Co-D 1T-MoS2) which demonstrated the lowest η10 of only 42 mV in all the reported MoS2 catalysts (Qi et al., 2019). The extraordinary HER activity was assigned to the ensemble effect of Co and S, which facilitated the hydrogen adsorption at the interface with ΔGH of 0.03 eV. Atomic Cu-doped 1T-MoS2 (Cu@MoS2) also showed promising HER performance with a η10 of 131 mV and a small Tafel slope of 51 mV dec−1. Structural characterization and theoretical analysis demonstrated that single-atom Cu doping not only stabilized the 1T phase but also facilitated the charge transfer (Ji et al., 2019). Deng et al. synthesized a novel N-doped and PO43--intercalated 1T/2H-MoS2 array ((N, PO43-)-MoS2/VG), which displayed a superior HER activity with a small η10 and Tafel slope of 85 mV and 42 mV dec-1, respectively (MoS2/VG with η10 of 187 mV and Tafel slope of 120 mV dec-1) (Deng et al., 2019). The outstanding HER performance was ascribed to the synergistic effect of N doping and PO43- intercalation, which decreased the band gap and lowered the d-band center and ΔGH.
Integrating 1T-MoS2 with conductive substrates such as carbon materials could not only stabilize the 1T phase but also increase the amount of exposed active sites to enhance the HER performance. For example, NH4+-intercalated 1T-MoS2 nanosheets grown on flexible single-walled carbon nanotubes (1T-MoS2/SWNT) exhibited a η10 as low as 108 mV and negligible activity loss after 3,000 cycles (Liu Q. et al., 2017). Electron donation from SWNT to 1T-MoS2 at the interface was beneficial for stabilizing the 1T phase and weakening the hydrogen adsorption energy. In addition, the ultra-small size of 1T-MoS2 nanopatches endowed a high density of active edges and basal planes. Wang et al. first constructed MoS2 nanoparticles on a three-dimensional carbon fiber paper to expose more edge sites and then conducted Li electrochemical intercalation to induce 1T phase formation and improve the electrical conductivity (Li-MoS2/CFP). Consequently, an ultrahigh HER activity with a η10 of 118 mV and a Tafel slope of 62 mV dec−1 was achieved (Wang H. et al., 2014). Similarly, reduced graphene oxide (RGO) was utilized as a template to grow 1T-MoS2 nanosheets, which donated electrons and promoted the 1T content from 15% to 50% (Cai et al., 2017). Accordingly, the 2H-MoS2 nanosheets exhibited a larger η10 of 348 mV and a Tafel slope of 90 mV dec−1. In contrast, the 1T-2H/RGO composites obtained a quite small η10 and a Tafel slope of 126 mV and 35 mV dec−1 due to numerous surface active sites and excellent charge transfer ability.
The aforementioned HER performance was obtained in the acidic medium (0.5 M H2SO4); however, developing efficient MoS2 HER catalysts under alkaline conditions will be more challenging because oxygen evolution reaction (OER) catalysts are usually unstable in the acidic medium. Gao et al. synthesized a highly efficient and stable carbon-doped 1T-2H/MoS2 nanosheets with 1T fraction of 60%, which exhibited a superb HER performance with a η10 of only 40 mV and Tafel slope of 46 mV dec-1 in 1.0 M KOH (Gao et al., 2020a). This is significantly reduced compared with those of 2H-MoS2/graphene oxide which has a η10 of 254 mV and a Tafel slope of 169 mV dec−1. The excellent electrochemical activity and stability was acquired by fast charge transfer and abundant active sites. The SA-Ru-MoS2 achieved a η10 as small as 76 mV in 1.0 M KOH (pure 2H-MoS2 with a poor η10 of 339 mV), which was attributed to reduced ΔGH, increased electrical conductivity, and modulated electronic structure (Zhang et al., 2019). Zhang et al. grew nickel hydr(oxy)oxide nanoparticles on the surface of 1T-MoS2 nanosheets to obtain 1T-MoS2/Ni2+δOδ(OH)2-δ hybrids, which displayed an excellent HER performance in 1.0 M KOH with a η10 of 73 mV and 185 mV smaller than those of the pristine 1T-MoS2. A mechanism study indicated that Ni2+δOδ(OH)2-δ nanoparticles promoted the adsorption and dissociation of H2O, hence providing sufficient H+ to produce H2 on the surface of 1T-MoS2 nanosheets (Zhang and Liang, 2018). Shang et al. embedded vertical monolayer 1T-MoS2 on the amorphous CoOOH substrate (MCSO), where the CoOOH substrate not only stabilized the metallic phase but also anchored the vertical 1T-MoS2 nanosheets to provide plenty of active sites (Shang et al., 2018). A small Tafel slope of 42 mV dec−1 and good stability of 25-h run time were achieved in the alkaline medium. Table 1 lists the HER performance of some representative 1T-MoS2 catalysts in both acidic and alkaline media in recent years. The phase modulation method, 1T content, and substrate were also summarized.
TABLE 1. HER performance of 1T-MoS2 catalysts in the reported literature.
Summary and perspectives
Herein, we first introduced a series of characterization techniques to confirm the presence and determine the content of 1T-MoS2. Then, some frequently used phase modulation strategies were summarized to realize the targeted synthesis and stabilization of 1T-MoS2. Finally, we presented some recent progress in improving the HER performance of 1T-MoS2 in both acidic and alkaline media including sulfur vacancy engineering, elemental doping, and integration with a conductive carbon substrate. However, there is still a possibility to optimize the synthesis and design efficient 1T-MoS2 HER catalysts for future research. 1) The synthetic parameters for controllable synthesis and stabilization of the metallic 1T phase. 2) Further modification or functionalization strategies for tuning the electronic structure and stabilizing the 1T phase need to be explored. 3) Further improvement in the HER performance of 1T-MoS2 in alkaline or neutral media due to the sluggish kinetics. 4) Investigating the synergism between 1T-MoS2 and other conductive substrates, such as nickel foam, which not only promote the exposure of more active sites but also offer better electrical conductivity.
Author contributions
YZ, LW, and QC drafted the manuscript. JC participated in the manuscript revision. CZ revised the manuscript and provided the funding support.
Funding
This work was financially supported by the National Natural Science Foundation of China (No. 22102055) and Natural Science Foundation of Hunan Province (No. 2021JJ40222).
Conflict of interest
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Publisher’s note
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Keywords: hydrogen evolution reaction, 1T-MoS2, phase modulation, characterization, electrocatalysts
Citation: Zhang Y, Wang L, Chen Q, Cao J and Zhang C (2022) Recent progress of electrochemical hydrogen evolution over 1T-MoS2 catalysts. Front. Chem. 10:1000406. doi: 10.3389/fchem.2022.1000406
Received: 22 July 2022; Accepted: 20 September 2022;
Published: 07 October 2022.
Edited by:
Shijie Li, Zhejiang Ocean University, ChinaReviewed by:
Feilong Gong, Zhengzhou University of Light Industry, ChinaSheng Ye, Anhui Agricultural University, China
Javier Quílez-Bermejo, Université de Lorraine, France
Copyright © 2022 Zhang, Wang, Chen, Cao and Zhang. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Jing Cao, Y2FvamluZ0BobmlzdC5lZHUuY24=; Cen Zhang, Y2VuemhhbmdAaG5pc3QuZWR1LmNu