3D N-Ti₃C₂T_x/Co/N-CNT composites as a sodiophilic framework for dendrite-free sodium metal anodes†

Yijing Zhou, Pengfei Huang, Hangjun Ying, Lucheng Cai, Chaowei He, Zuojie Xu and Wei-Qiang Han*
School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China. E-mail: hanwq@zju.edu.cn

First published on 7th August 2024

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1. Introduction

The issues of energy crisis and environmental pollution compel us to optimize the energy structure.^1,2 In this regard, renewable energy sources, such as wind and solar, have gradually gained wide attention.^3,4 To address the issues of intermittency and instability associated with renewable energy, efficient and cost-effective large-scale energy storage systems have attracted intensive attention.⁵ Although lithium-based batteries currently dominate the market of electrochemical energy storage systems, the limited lithium resources encourage researchers to explore alternative technologies.^6–8 Sodium-based batteries exhibit a similar working principle to lithium-based batteries and possess some advantages such as abundant resources, low cost, excellent safety and low-temperature performance.^9–11 As a result, sodium-based batteries have been extensively researched in the past few years.

Among the various anodes of sodium-based batteries, Na metal exhibits excellent prospects for practical applications due to its high theoretical specific capacity (1166 mA h g⁻¹) and low working potential.^12–14 However, the Na metal anode also encounters some issues such as the unstable solid–electrolyte interphase (SEI) layer, Na dendrite growth, huge volume variation, formation of “dead Na”, etc.¹⁵ To tackle these challenges, a series of strategies including electrolyte modification,^16–18 artificial SEI layer construction^19–21 and the utilization of solid-state electrolytes have been proposed.^22–24 Constructing a sodiophilic three-dimensional (3D) framework is a straightforward and practical strategy, which can not only accommodate the substantial volume change of Na metal upon cycling but also induce the nucleation and growth process of Na metal, thereby achieving enhanced cyclic performance.²⁵ In 2022, Li's group fabricated a 3D framework by combining N-doped carbon nanofibers with MoS₂,²⁶ and the coulombic efficiency could reach 99.6% after 3000 cycles at 8 mA cm⁻² due to the good sodiophilicity of this 3D framework.

MXenes, a new class of two-dimensional (2D) materials, are generally synthesized by etching the A-site atoms from MAX phases (M = early transition metal, A = Al, Si, Ga, etc., X = C and/or N) and possess a formula of M_n+1X_nT_x (T = –O, –OH, –F, –P, etc.).^27,28 Due to the superior electronic conductivity, Na⁺ diffusion kinetics and the presence of sodiophilic functional groups (–O and –F), MXenes have attracted widespread attention in the field of Na metal batteries.^29,30 Over the past few years, a series of 3D composite frameworks containing MXenes and secondary sodiophilic species have been successfully synthesized, such as Mg(II)@Ti₃C₂ and Sn(II)@Ti₃C₂,^31,32 which can achieve dendrite-free growth of Na metal. Additionally, one-dimensional (1D) carbon nanotubes (CNTs), known for their high electronic conductivity, are often introduced into MXenes to prevent the restacking of MXene nanosheets and further enhance the electronic conductivity.^33,34 In previous studies, in order to prepare MXene/CNT composites, researchers first synthesized MXenes by etching the MAX phases with highly corrosive fluorine-containing reagents³⁵ and metal ions were then introduced into the MXene, followed by the addition of a carbon source to induce the growth of CNTs during the annealing process,^36–38 which makes the fabrication process typically hazardous and complex. In 2019, Prof. Huang's group proposed a novel and safe route for synthesizing MXene/metal composites by etching the MAX phases with Lewis acidic molten salts (FeCl₂, CoCl₂, NiCl₂, etc.).³⁹ Typically, researchers remove the metal from MXene/metal composites to obtain pure MXenes, which results in economic loss. Hence, realizing the rational utilization of the obtained metal is of great significance.

Based on all the above considerations, we propose a safe and simple method for growing N-doped carbon nanotubes (N-CNTs) on N-doped Ti₃C₂T_x (N-Ti₃C₂T_x) MXenes to construct a 3D framework. Specifically, Ti₃C₂T_x/Co hybrids are first prepared by etching Ti₃AlC₂ precursors with CoCl₂·6H₂O Lewis acidic salts, and the obtained Ti₃C₂T_x/Co is then thoroughly mixed with melamine, and N-Ti₃C₂T_x/Co/N-CNT (TCC) can be fabricated after the high-temperature annealing process. To verify the universality of this method, Ti₃C₂T_x/Fe and Ti₃C₂T_x/Ni are also synthesized via FeCl₂·4H₂O or NiCl₂ etching of Ti₃AlC₂, and both of them can successfully induce the growth of N-CNTs. This method fully utilizes the obtained metals during the Lewis acidic etching process, which avoids the introduction of additional metal species for the growth of N-CNTs, greatly simplifying the fabrication process and enhancing experimental safety. When used as frameworks for Na plating/stripping, TCC composites possess the following advantages: (i) N-Ti₃C₂T_x MXenes, Co metal, and N-CNTs all exhibit outstanding electrical conductivity, which allows this 3D framework to reduce the local current density; (ii) the 3D TCC framework facilitates sufficient contact between the electrode and electrolyte, which is beneficial for rapid Na⁺ diffusion; (iii) the 3D TCC framework can buffer the volume changes of Na metal upon cycling, greatly protecting the formed SEI film; (iv) the –O termination in Ti₃C₂T_x and nitrogen species (pyridinic N and pyrrolic N) in N-CNT exhibit excellent sodiophilicity and can effectively induce uniform Na nucleation and smooth deposition within the 3D TCC framework. As a result, asymmetric cells with a TCC electrode present low nucleation potential and stable cycling performance, with an average coulombic efficiency of 99.9% at 2 mA cm⁻² and 4 mA h cm⁻², and TCC–Na symmetric cells can achieve reversible Na stripping/plating for 1300 h at 1 mA cm⁻² and 1 mA h cm⁻². Moreover, TCC–Na//Na₃V₂(PO₄)₃ full cells maintain high capacity retention of 85.5% after 1200 cycles at a current density of 4C.

2. Experimental section

2.1 Preparation of Ti₃C₂T_x/Co hybrids

The Ti₃C₂T_x/Co was prepared based on the Lewis acidic etching method.³⁹ First, 1 g Ti₃AlC₂ and 3.66 g CoCl₂·6H₂O were mixed and ground in a mortar for 10 min, and then 0.6 g NaCl and 0.76 g KCl were then added into the above mixture and ground for 10 min. After that, the mixture was transferred into a porcelain boat and placed in a tube furnace for annealing at 750 °C for 20 h (heating rate: 4 °C min⁻¹). The samples were annealed under an argon atmosphere. Subsequently, the samples were collected and washed with deionized water several times. Finally, the Ti₃C₂T_x/Co hybrids can be obtained after vacuum-drying for 12 h.

2.2 Preparation of Ti₃C₂T_x/Fe and Ti₃C₂T_x/Ni hybrids

The Ti₃C₂T_x/Fe and Ti₃C₂T_x/Ni were also prepared via Lewis acidic etching under an argon atmosphere, except that CoCl₂·6H₂O was replaced by FeCl₂·4H₂O and NiCl₂.

2.3 Preparation of N-Ti₃C₂T_x/Co/N-CNT hybrids

The N-Ti₃C₂T_x/Co/N-CNT (TCC) composites were prepared by a straightforward annealing process. 300 mg Ti₃C₂T_x/Co and 2 g melamine were mixed thoroughly in a mortar, and the mixture placed in a porcelain boat was then transferred into a tube furnace under an argon atmosphere and heated at 700 °C for 3 h (heating rate: 2 °C min⁻¹), leading to the successful preparation of TCC hybrids. N-Ti₃C₂T_x/Fe₃C/N-CNT (TFC) and N-Ti₃C₂T_x/Ni/N-CNT (TNC) were prepared under an argon atmosphere in the same way, except that Ti₃C₂T_x/Co was replaced by Ti₃C₂T_x/Fe and Ti₃C₂T_x/Ni.

2.4 Materials characterization

The X-ray diffraction (XRD) patterns of the materials were obtained using a Rigaku MiniFlex 600 X-ray diffractometer, employing a Cu K_α radiation source, with a 2θ range of 2° to 80°. The morphology of the samples was characterized by field-emission scanning electron microscopy (FESEM, Hitachi SU-8010) and transmission electron microscopy (TEM, FEI Tecnai F20). The adsorption/desorption isotherms and pore-size distribution were analyzed using a Micromeritics ASAP 2020 Plus HD88 instrument. A Thermo Scientific K-Alpha X-ray photoelectron spectrometer was used to investigate the bonding states of the samples.

2.5 Electrochemical measurements

The electrode slurry consisted of TCC and a sodium carboxymethylcellulose (CMC) binder with a weight ratio of 9:1, the slurry was then coated onto Cu foil and placed in a vacuum oven and dried overnight at 60 °C. Subsequently, the electrode was punched into cells with a diameter of 14 mm and the mass loading was around 1.3 mg cm⁻². The electrolyte was 1 M NaPF₆ in diethylene glycol dimethyl ether (DEGDME) (50 μL for asymmetric cells and symmetric cells, 100 μL for full cells). For asymmetric cells, Na metal was used as the counter electrode and the separator was Celgard 2300. For symmetric cells, a certain amount of Na metal was pre-deposited on the TCC electrode and Cu foil. For full cells, the Na₃V₂(PO₄)₃ (NVP) electrode was first prepared and used as the cathode. NVP, Super P and polyvinylidene fluoride (PVDF) were mixed in a mass ratio of 8:1:1 and stirred for 6 h to form a uniform slurry, and the slurry was then evenly coated onto carbon-coated Al foil and dried overnight in a vacuum oven at 60 °C. The loading of the NVP electrode was approximately 4 mg cm⁻² and the separator was a glass fiber membrane (GF/F). After that, the metallic Na was pre-deposited on the TCC electrode to make capacity ratio of negative to positive electrode (N/P ratio) reach 5:1. EIS measurements were performed with a Solartron 1470E electrochemical workstation, and the frequency was in the range of 10⁻¹ to 10⁶ Hz.

3. Results and discussion

The preparation process of TCC is shown in Fig. 1. The Ti₃C₂T_x/Co mixture was obtained via a Lewis acidic molten salt etching method. Specifically, the Ti₃AlC₂ MAX phase was immersed in molten CoCl₂·6H₂O at 750 °C with KCl and NaCl providing a molten salt environment. The Al atoms in the Ti₃AlC₂ MAX are oxidized to Al³⁺ by Co²⁺, and the Al element is released in the form of AlCl₃ gas. Simultaneously, Co²⁺ can be reduced to Co metal, which is loaded on the surface and in the interlayer of Ti₃C₂T_x MXenes. Eqn (1)–(4) describe this reaction in detail. Then, melamine with abundant carbon and nitrogen sources was added into Ti₃C₂T_x/Co hybrids and subjected to high temperature; the Co nanoparticles can successfully induce the growth of N-CNTs during the annealing process. Meanwhile, the Ti₃C₂T_x MXene can also be doped with N elements to form N-Ti₃C₂T_x, thus leading to the preparation of TCC composites.

2Ti3AlC2 + 3CoCl2 → 2Ti3C2 + 2AlCl3↑ + 3Co	(1)

Ti3C2 + CoCl2 → Ti3C2Cl2 + Co	(2)

Ti3C2 + 2H2O → Ti3C2(OH)2 + H2	(3)

Ti3C2(OH)2 → Ti3C2O2 + H2	(4)

The XRD patterns of as-prepared materials are shown in Fig. 2a, from which it can be observed that the (104) peak of Ti₃AlC₂ MAX at 38.9° has disappeared after CoCl₂·6H₂O etching, indicating the successful removal of the Al layer and the synthesis of Ti₃C₂T_x MXenes.⁴⁰ In addition, the (002) peak of Ti₃AlC₂ MAX at 9.7° has left shifted to 8.1° for Ti₃C₂T_x MXenes, suggesting the enlarged interlayer spacing. At the same time, the peaks at 44.2°, 51.5°, and 75.9° can be assigned to the Co metal (PDF#89-4307) for Ti₃C₂T_x/Co. Similarly, after FeCl₂·4H₂O or NiCl₂ etching, it can be seen that the diffraction peaks of Ni (PDF#89-7128) and Fe (PDF#89-7128) can be observed in the XRD patterns of Ti₃C₂T_x/Ni and Ti₃C₂T_x/Fe, respectively. Additionally, the (002) peak of the Ti₃C₂T_x MXene in Ti₃C₂T_x/Ni and Ti₃C₂T_x/Fe has also left shifted to around 7.8°. The above results strongly prove the successful synthesis of Ti₃C₂T_x/Co, Ti₃C₂T_x/Ni and Ti₃C₂T_x/Fe hybrids.

Moreover, the peak at around 27° corresponding to the (002) peak of CNTs can be observed in the XRD patterns of prepared TCC, TNC and TFC.⁴¹ For TCC and TNC hybrids, the diffraction peaks of Co or Ni metal can still be seen. However, the diffraction peaks of Fe metal disappear and the characteristic peaks of Fe₃C (PDF#72-1110) emerge for TFC composites. The specific surface area of the as-prepared samples was investigated through N₂ adsorption–desorption isotherms (Fig. 2b, d and f), and the specific surface area of TCC, TNC and TFC is calculated to be 62.7, 71.3 and 62.1 m² g⁻¹, respectively, which are larger than that of Ti₃C₂T_x/Co (27.54 m² g⁻¹), Ti₃C₂T_x/Ni (38.78 m² g⁻¹) and Ti₃C₂T_x/Fe (57.85 m² g⁻¹) hybrids, indicating the formation of 3D architecture. Furthermore, the pore sizes of TCC, TNC and TFC are predominantly centered at around 3.93, 3.81 and 3.88 nm, respectively, proving the formation of a mesoporous structure (Fig. 2c, e and g). Such a mesoporous structure and high specific surface area of TCC, TNC and TFC can facilitate electrolyte permeation and Na⁺ diffusion kinetics,^42,43 which is conducive to the improvement of electrochemical performance.

The morphology of the obtained materials was first analyzed using SEM images. The typical densely-packed architecture can be observed for Ti₃AlC₂ MAX (Fig. S1, ESI†). After CoCl₂·6H₂O, FeCl₂·4H₂O or NiCl₂ etching of the Ti₃AlC₂ precursor, the accordion-like layered structure of Ti₃C₂T_x MXene is clearly visible for Ti₃C₂T_x/Co, Ti₃C₂T_x/Ni and Ti₃C₂T_x/Fe hybrids, and Fe, Co or Ni metal nanoparticles are loaded on the surface and in the large interlayer gap of Ti₃C₂T_x MXenes (Fig. 3a–c and Fig. S2–S4, ESI†). Subsequently, abundant 1D CNTs can be seen in TCC, TNC and TFC hybrids after the high-temperature annealing process (Fig. 3d–f), effectively confirming the feasibility of the proposed strategy.

XPS measurement was performed to investigate the surface chemical bonding of various samples. For TCC, Ti 2p spectra exhibit two sets of spin–orbit splitting peaks (2p_3/2 and 2p_1/2), and it can be deconvoluted into five sets of peaks including Ti–C (I) (455/460.6 eV), Ti–C (II) (455.8/461.5 eV), Ti–N (456.9/462.6 eV), Ti–Cl (458.0/463.5 eV), and Ti–O (458.8/464.5 eV) (Fig. 4a).^38–40 The presence of Ti–N bonds indicates that the N element from melamine has been successfully doped into Ti₃C₂T_x, and the Ti–Cl bond can also be observed in the Cl 2p spectra (Fig. S5, ESI†). The emergence of Ti–O and Ti–Cl bonds proves that N-doped Ti₃C₂T_x MXenes are terminated by –O and –Cl groups. The C 1s spectra contain C–C (284.8 eV), C–N (285.3 eV), C–O (286.6 eV) and O–CO (288.7 eV) bonds and the presence of C–N bonds suggests the doping of N elements into Ti₃C₂T_x and CNTs (Fig. 4b).^36,44 The N 1s spectra contain five distinct chemical states of nitrogen: Ti–N (396.7 eV), pyridinic N (398.7 eV), pyrrolic N (399.6 eV), graphitic N (401.1 eV) and oxidized N (403.3 eV) (Fig. 4c).^45,46 The graphitic N can enhance the electronic conductivity of TCC, facilitating rapid charge transfer,⁴⁷ and pyrrolic N and pyridinic N can promote the formation of defects and active sites.^45,48 It is noteworthy that the –O termination, pyridinic N and pyrrolic N in TCC hybrids exhibit superior sodiophilicity according to previous works,^49–51 which is beneficial for Na uniform deposition. For TFC and TNC, the N 1s spectra can also be fitted into above-mentioned five types of nitrogen (Fig. 4e and f), confirming the successful doping of the N element. Additionally, the characteristic Fe–C peak at 709.3 eV belonging to Fe₃C can be observed in the Fe 2p spectra of TFC (Fig. 4d).⁵² The XPS spectra of Co 2p and Ni 2p are also shown in the ESI† (Fig. S6, ESI†).

TEM, high-resolution transmission electron microscopy (HRTEM) and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) images were obtained to further characterize the morphology of TCC. It is clear that zero-dimensional (0D) Co nanoparticles are encapsulated inside 1D N-CNTs, and 1D N-CNTs are then loaded onto the surface of 2D N-Ti₃C₂T_x MXenes, forming a unique 3D framework (Fig. 5a and b). The HRTEM image in Fig. 5c indicates the presence of the Co (111) plane with a lattice spacing of 0.206 nm and the N-CNTs (002) plane with an interplanar spacing of 0.388 nm. The HAADF-STEM and elemental mapping images confirm the uniform distribution of C, O, N, Ti, Cl and Co elements in TCC hybrids (Fig. 5d–i and Fig. S7, ESI†).

As a proof of concept, TCC hybrids are selected as a 3D sodiophilic framework for Na plating/stripping to investigate its electrochemical performance. Due to the excellent electronic conductivity of TCC, no additional conductive agents such as Super P were introduced into the TCC electrode, which is beneficial for the increase of energy density. The voltage–capacity curves of the asymmetric cells were tested at different current densities (Fig. 6a and b). Bare Cu foil exhibits a nucleation overpotential of 24 mV at a current density of 0.5 mA cm⁻², while TCC demonstrates a much smaller nucleation overpotential of 5 mV (Fig. 6a), indicating the greatly increased sodiophilicity of TCC. When the current density increases to 1 mA cm⁻², TCC also exhibits a low nucleation overpotential of 6 mV (Fig. 6b). The EIS spectra were used to explore the kinetics of asymmetric cells, and it can be observed that the TCC electrode exhibits a lower charge transfer resistance (R_ct) compared with Cu foil and the Ti₃C₂T_x/Co electrode, suggesting enhanced Na plating/stripping kinetics for TCC (Fig. 6c and Fig. S8, ESI†). As shown in Fig. 6d and e, TCC frameworks demonstrate stable coulombic efficiencies at various current densities and areal capacities, for example, the TCC electrode can achieve the reversible Na plating/stripping process for 600 cycles at 2 mA cm⁻² and 4 mA h cm⁻² with an average coulombic efficiency of 99.9% (Fig. 6e). However, Cu foil delivers extremely unstable coulombic efficiency at various current densities, again revealing its sodiophobic feature. Additionally, the highly overlapped voltage–capacity curves of the TCC electrode again proves its outstanding cyclic stability (Fig. S9, ESI†).

Symmetric cells were fabricated to further investigate the Na plating/stripping of various frameworks. The EIS spectra of various symmetric cells are shown in Fig. 6f, with a Na pre-deposition of 8 mA h cm⁻². TCC–Na symmetric cells present lower R_ct than Cu–Na symmetric cells, which indicates more rapid reaction kinetics for TCC–Na symmetric cells. As shown in Fig. 6g, TCC–Na symmetric cells (Na pre-deposition: 4 mA h cm⁻²) exhibit a low overpotential of 14 mV and excellent long-term cycle stability over 1300 h at a current density of 1 mA cm⁻² and an areal capacity of 1 mA h cm⁻² with a depth of discharge (DOD) of 25%. When the current density and areal capacity are increased to 2 mA cm⁻² and 4 mA h cm⁻², respectively, TCC–Na symmetric cells (Na pre-deposition: 8 mA h cm⁻²) can still stably cycle for 600 h with a DOD of 50% (Fig. 6h). In contrast, Cu–Na symmetric cells display large overpotential and unstable voltage–time curves, which can be attributed to the formation of Na dendrites and “dead Na” as well as unstable SEI films. Based on the above discussion, it can be inferred that the TCC electrode exhibits excellent electrochemical performance without the addition of conductive agents.

The ex situ SEM images were used to investigate the Na plating/stripping behavior of Cu foil and TCC. The SEM images of the TCC electrode and bare Cu foil before Na deposition are shown in Fig. S10 (ESI†). When the Na deposition amount reaches 1 mA h cm⁻², uneven nucleation and loose Na deposition occur on bare Cu foil (Fig. 7a), but it is observed that the uniform nucleation can be successfully achieved for TCC frameworks owing to its good sodiophilicity (Fig. 7e). When the Na deposition amount increases to 3 mA h cm⁻², the deposited Na on the Cu foil still remains uneven and loose, while the deposited Na on TCC begins to become dense and smooth (Fig. 7b and f). As the Na deposition amount further rises, smooth and dense Na layers can be obtained for TCC, while Cu foil fails to achieve smooth Na deposition, thus facing the risk of dendrite growth, which can potentially pierce the separator and lead to safety incidents (Fig. 7c, d, g and h). The schematic of Na plating behavior on Cu and TCC is shown in Fig. 7i, from which it can be seen that TCC frameworks can achieve uniform Na nucleation and dendrite free deposition owing to the presence of sodiophilic species (pyridinic N, pyrrolic N and -O groups), whereas Cu foil fails to achieve even Na deposition due to its sodiophobic nature.

Full cells were finally assembled to assess the practical application of TCC, and NVP and Na-deposited TCC were used as the cathode and anode, respectively. As shown in Fig. 8a, the overpotential of TCC–Na//NVP is significantly lower than that of Cu–Na//NVP full cells, indicating the improved kinetics for TCC–Na//NVP full cells. The charge–discharge curves of full cells after different cycles at 5C are displayed in Fig. 8b and c, from which it can be observed that the Cu–Na//NVP full cell exhibits poor cyclic stability and fails only after 48 cycles owing to the formation of Na dendrites. In contrast, the charge–discharge curves of TCC–Na//NVP cells highly overlap. The long-term cycling performance of various full cells is demonstrated in Fig. 8d and e. TCC–Na//NVP full cells stably cycle for 1200 cycles with a capacity retention of 85.5% at a current density of 4C. When the current density increases to 5C, TCC–Na//NVP full cells also exhibit excellent cyclic stability with a discharge capacity of 82.5 mA h g⁻¹ over 900 cycles. Nevertheless, Cu–Na//NVP full cells demonstrate poor cyclic performance at various current densities. Finally, the light emitting diode panel with “ZJU” letter can be successfully lit by TCC–Na//NVP full cells, indicating practical application prospects (Fig. S11, ESI†).

4. Conclusions

In summary, Ti₃C₂T_x/Co, Ti₃C₂T_x/Fe and Ti₃C₂T_x/Ni were first synthesized via the Lewis acidic molten salt etching method, and N-CNTs were then grown on the N-Ti₃C₂T_x MXene during the annealing process based on the induction effect of metal nanoparticles, finally resulting in the fabrication of 3D TCC, TFC and TNC frameworks. The proposed method realizes the effective utilization of the Lewis acidic etching products, and exhibits good universality, high safety and simplicity. The obtained 3D framework possesses various advantages as follows: (1) the pyridinic N, pyrrolic N and –O functional groups exhibit great sodiophilicity, which can decrease the Na nucleation overpotential and induce Na deposition; (2) a large specific surface area provides larger contact area between the electrolyte and electrode, thereby boosting the Na⁺ migration kinetics; (3) 3D framework can buffer huge volume variation of the Na metal during repeated Na plating/stripping processes, greatly enhancing the cyclic stability; (4) the N-CNT, metal species and N-Ti₃C₂T_x all display superior electronic conductivity, greatly decreasing the local current density of 3D frameworks. Accordingly, as a proof of concept, TCC frameworks can deliver an ultralow nucleation overpotential of 6 mV and an average coulombic efficiency of 99.9%, and the TCC–Na symmetric cells can achieve reversible cycling for 1300 h under 1 mA cm⁻² and 1 mA h cm⁻². More importantly, TCC–Na//NVP full cells can stably cycle for 1200 cycles with a capacity retention of 85.5% at a current density of 4C. This work opens an avenue for the preparation of MXene/CNTs composites, which may inspire more research studies.

Data availability

Data are available upon request from the corresponding author.

Conflicts of interest

There are no conflicts to declare.

Acknowledgements

This work was supported by the funds from Technologies R&D Program of Huzhou City (2022JB01), “Dongjiang Talent Program” of Qidong City, the Key Research and Development Program of Zhejiang Province (2023C01127) and the Highstar Corporation HSD20210118.

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Footnote

† Electronic supplementary information (ESI) available. See DOI: https://doi.org/10.1039/d4tc02740j

This journal is © The Royal Society of Chemistry 2024