In situ polymerization preparation and characterization of Li_4Ti_5O_(12)-polyaniline anode material

Li4Ti5O12 powders were prepared by so-gel method using tetrabutyl titanate,lithium acetate and absolute alcohol as starting materials.Li4Ti5O12-polyaniline(Li4Ti5O12-PAn)composite was prepared by in situ polymerization method using aniline, ammonium persulfate and hydrochloricarried as starting materials.Li4Ti5O12-PAn composite was characterized by X-ray diffractometry(XRD),infrared spectrum(IR)combined with electrochemical tests.The results show that the electrical conductivity is enhanced obviously due to the introduction of PAn to Li4Ti5O12.Li4Ti5O12-PAn composite exhibits better high-rate capability and cyclability than Li4Ti5O12.The composite can deliver a specific capacity of 191.3 and 148.9 mA·h/g,only 0.13%and 0.61%of the capacity is lose after being discharged 80 times at 0.1C and 2.0C,respectively.

Thermal Stability and Crystallinity Study of Polystyrene/SiO2 Nano-Composites Synthesis via Microwave-Assisted In Situ Polymerization

Serials of polystyrene/SiO2 Nano composites (PS/SiO2) with different content of inorganic fillers were successfully prepared by the in situ bulk radical polymerization of styrene under microwave irradiation. The effect of the amount of Nano SiO2 on the properties of the PS/SiO2 Nanocomposites along with the average relative molecular masses (Mn, Mz and Mw) was investigated by thermal analysis and X-Ray Diffraction (XRD). Their structural model was proposed on the basis of the Optical Microscopy, FTIR (Fourier Transform Infrared) analysis, differential scanning calorimetry (DSC), gel permeation chromatography (GPC) and X-Ray Diffraction (XRD). The dispersion of nanoparticles in Polystyrene is observed in the magnified image. The effect of microwave irradiation power on molecular weight of polystyrene was also studied. It was found that, the microwave assisted reaction needs less time as compare to conventional polymerization and found to be in between 10 to 15 min.

Progress and perspectives of in situ polymerization method for lithium-based batteries

The application of lithium-based batteries is challenged by the safety issues of leakage and flammability of liquid electrolytes.Polymer electrolytes(PEs)can address issues to promote the practical use of lithium metal batteries.However,the traditional preparation of PEs such as the solution-casting method requires a complicated preparation process,especially resulting in side solvents evaporation issues.The large thickness of traditional PEs reduces the energy density of the battery and increases the transport bottlenecks of lithium-ion.Meanwhile,it is difficult to fill the voids of electrodes to achieve good contact between electrolyte and electrode.In situ polymerization appears as a facile method to prepare PEs possessing excellent interfacial compatibility with electrodes.Thus,thin and uniform electrolytes can be obtained.The interfacial impedance can be reduced,and the lithium-ion transport throughput at the interface can be increased.The typical in situ polymerization process is to implant a precursor solution containing monomers into the cell and then in situ solidify the precursor under specific initiating conditions,and has been widely applied for the preparation of PEs and battery assembly.In this review,we focus on the preparation and application of in situ polymerization method in gel polymer electrolytes,solid polymer electrolytes,and composite polymer electrolytes,in which different kinds of monomers and reactions for in situ polymerization are discussed.In addition,the various compositions and structures of inorganic fillers,and their effects on the electrochemical properties are summarized.Finally,challenges and perspectives for the practical application of in situ polymerization methods in solid-state lithium-based batteries are reviewed.

A fiber-reinforced solid polymer electrolyte by in situ polymerization for stable lithium metal batteries

Solid polymer electrolytes(SPEs)by in situ polymerization are attractive due to their good interfacial contact with electrodes.Previously reported in situ polymerized SPEs,however,suffer from the low polymerization degree that causes poor mechanical strength,Li dendrite penetration,and performance decay in Li-metal batteries.Although highly polymerized SPEs are more stable than lowly polymerized ones,they are restricted by their sluggish long-chain mobility and poor ionic conductivity.In this work,a three-dimensional fibrous membrane with ion selectivity was prepared and used as a functional filler for the in situ formed SPE.The obtained SPE has high stability due to its high polymerization degree after the long-term heating process.The fibrous membrane plays a vital role in improving the SPE’s properties.The rich anion-adsorption sites on the fibrous membrane can alleviate the polarization effect and benefit a uniform current distribution at the interface.The fibrous nanostructure can efficiently interact with the polymeric matrix,providing rich hopping sites for fast Li+migration.Consequently,the obtained SPE enables a uniform Li deposition and long-term cycling performance in Li-metal batteries.This work reported an in situ formed SPE with both high polymerization degree and ionic conductivity,paving the way for designing high-performance SPEs with good comprehensive properties.

Gel electrolyte via in situ polymerization to promote durable lithium-air batteries

Aprotic lithium-air batteries(LABs)have been known as the holy grail of energy storage systems due to their extremely high energy density.However,their real-world application is still hindered by the great challenges from the Li anode side,like dendrite growth and corrosion reactions,thus a pure oxygen atmosphere is usually adopted to prolong the lifetime of LABs,which is a major obstacle to fully liberate the energy density advantages of LABs.Here,a gel polymer electrolyte has been designed through in-situ polymerization of 1,3-dioxolane(DOL)by utilizing the unique semi-open nature of LABs to protect the Li anode to conquer its shortcomings,enabling the high-performance running of LABs in the ambient air.Unlike common liquid electrolytes,the in-situ formed gel polymer electrolyte could facilitate constructing a gradient SEl film with the gradual decrease of organic components from top to bottom,preventing the Li anode from dendrite growth and air-induced corrosion reactions and thus realizing durable Li repeated plating/stripping(2000h).Benefiting from the anode protection effects of the gradient SEI film,the LABs display a long lifetime of 17o cycles,paving an avenue for practical,long-term,and high-efficiency operation of LABs.

In Situ Directional Polymerization of Poly(1,3-dioxolane)Solid Electrolyte Induced by Cellulose Paper-Based Composite Separator for Lithium Metal Batteries

In traditional in situ polymerization preparation for solid-state electrolytes,initiators are directly added to the liquid precursor.In this article,a novel cellulose paper-based composite separator is fabricated,which employs alumina as the inorganic reinforcing material and is loaded with polymerization initiator aluminum trifluoromethanesulfonate.Based upon this,a separator-induced in situ directional polymerization technique is demonstrated,and the extra addition of initiators into liquid precursors is no longer required.The polymerization starts from the surface and interior of the separator and extends outward with the gradually dissolving of initiators into the precursor.Compared with its traditional counterpart,the separator-induced poly(1,3-dioxolane)electrolyte shows improved interfacial contact as well as appropriately mitigated polymerization rate,which are conducive to practical applications.Electrochemical measurement results show that the prepared poly(1,3-dioxolane)solid electrolyte possesses an oxidation potential up to 4.4 V and a high Li+transference number of 0.72.After 1000 cycles at 2 C rate(340 mA g^(−1)),the assembled Li||LiFePO_(4)solid battery possesses a 106.8 mAh g^(−1)discharge capacity retention and 83.5%capacity retention ratio,with high average Coulombic efficiency of 99.5%achieved.Our work may provide new ideas for the design and application of in situ polymerization technique for solid electrolytes and solid batteries.

In situ polymerization of 1,3-dioxolane infiltrating 3D garnet framework with high ionic conductivity and excellent interfacial stability for integrated solid-state Li metal battery

The polymer-ceramic composite electrolyte is considered as one of promising electrolytes for solid-state battery.However,in previous research,ceramic particles are usually dispersed in polymer matrix and could not form continuous Li+conductive channels.The agglomeration of ceramic particles could also lead to low ionic conductivity and poor interfacial electrode/electrolyte contact.In this paper,self-supported porous Li_(6.4)La_(3) Zr_(1.4)Ta_(0.6)O_(12)(LLZTO) electrolyte is synthesized by gelcasting process,which possesses three-dimensional(3D) interconnected pore channels and relatively high strength.The 1,3-dioxolane(DOL) could penetrate into the porous LLZTO framework for its excellent fluidity.The subsequent in situ polymerization process by thermal treatment could completely fill the internal pores and improve the interfacial contact with electrode.The resulting 3D composite electrolyte with dual continuous Li+transport channels in ceramic and polymer components exhibits high ionic conductivity of 2.8 × 10^(-4) S·cm^(-1) at room temperature and low Li/electrolyte interfacial resistance of 94 Ω·cm^(2) at 40 ℃.The corresponding Li/Li symmetric cell delivers stable voltage profiles for over 600 h under 0.1 and 0.2 mA·cm^(-2).The solid-state Li/LiFePO_(4) battery shows superior rate and cycling performance under 0.1 C and 0.2 C.This work guides the preparation of composite electrolyte with dual continuous Li+conductive paths as well as high ceramic ratio and interface modification strategy for solid-state Li metal battery.

Thermoelectric properties of Bi_(0.5)Sb_(1.5)Te_3/polyaniline composites prepared by mechanical blending and in-situ polymerization

Bi 0.5 Sb 1.5 Te 3/polyaniline composites were prepared by mechanical blending and in situ polymerization, and their transport properties were measured. It was found that for the composites with 1%, 3%, 5% and 7% polyaniline (mass fraction) respectively, which were prepared by mechanical blending, the power factors decrease by about 30%, 50%, 55% and 65% compared with the Bi 0.5 Sb 1.5 Te 3 samples, which is mainly due to the remarkable decreases of the electrical conductivity. The electrical conductivity and power factor of the composites samples with 7% polyaniline prepared by in situ polymerization are higher by about 65% and 60%, respectively, than that of the corresponding samples prepared by mechanical blending.

Covalent organic frameworks-incorporated thin film composite membranes prepared by interfacial polymerization for efficient CO_(2) separation

Thin film composite(TFC)membranes with nanofillers additives for CO_(2)separation show promising applications in energy and environment-related fields.However,the poor compatibility between nanofillers and polymers in TFC membranes is the main problem.In this work,covalent organic frameworks(COFs,TpPa-1)with rich ANHA groups were incorporated into polyamide(PA)segment via in situ interfacial polymerization to prepare defect-free TFC membranes for CO_(2)/N_(2)separation.The formed covalent bonds between TpPa-1 and PA strengthen the interaction between nanofillers and polymers,thereby enhancing compatibility.Besides,the incorporated COFs disturb the rigid structure of the PA layer,and provide fast CO_(2)transfer channels.The incorporated COFs also increase the content of effective carriers,which enhances the CO_(2)facilitated transport.Consequently,in CO_(2)/N_(2)mixed gas separation test,the optimal TFC(TpPa_(0.025)-PIP-TMC/m PSf)membrane exhibits high CO_(2)permeance of 854 GPU and high CO_(2)/N_(2)selectivity of 148 at 0.15 MPa,CO_(2)permeance of 456 GPU(gas permeation unit)and CO_(2)/N_(2)selectivity of 92 at 0.5 MPa.In addition,the Tp Pa_(0.025)-PIP-TMC/m PSf membrane also achieves high permselectivty in CO_(2)/CH_(4)mixed gas separation test.Finally,the optimal TFC membrane showes good stability in the simulated flue gas test,revealing the application potential for CO_(2)capture from flue gas.

Tailoring the interaction of covalent organic framework with the polyether matrix toward high-performance solid-state lithium metal batteries

Solid polymer electrolyte is one of the most promising avenues to construct next-generation energy storage systems with high energy density,high safety,and flexibility,yet the low ionic conductivity at room temperature and poor high-voltage tolerance have limited their practical applications.To address the above issues,we design and synthesize a highly crystalline,vinyl-functionalized covalent organic framework(V-COF)rationally grafted with ether-based segments through solvent-free in situ polymerization.V-COF can afford a fast Li+conduction highway along the one-dimensional nanochannels and improve the high-voltage stability of ether-based electrolytes due to the rigid and electrochemically stable networks.The as-formed solid-state electrolyte membranes demonstrate a superior ionic conductivity of 1.1×10^(−4)S cm^(−1)at 40℃,enhanced wide electrochemical window up to 5.0 V,and high Young's modulus of 92 MPa.The Li symmetric cell demonstrates ultralong stable cycling over 600 h at a current density of 0.1 mA cm^(−2)(40℃).The assembled solid-state Li|LiFePO4 cells show a superior initial specific capacity of 136 mAh g^(−1)at 1 C(1 C=170 mA g^(−1))and a high capacity retention rate of 84%after 300 cycles.This study provides a novel and scalable approach toward high-performance solid ether-based lithium metal batteries.

Double-layer solid-state electrolyte enables compatible interfaces for high-performance lithium metal batteries

Solid-state lithium metal batteries are promising next-generation batteries for both micro-scale integrated electronic devices and macro-scale electric vehicles.However,electrochemical incompatibility between electrolyte and electrodes causes continuous performance degradation.Here,we report a unique design of a double-layer composite solid-state electrolyte(D-CSE),where each layer,composed of both polymer and ceramics,is electrochemically compatible with its contacting electrode(Li anode or LiCoO_(2)cathode).The D-CSE has a small thickness(50μm),high thermal stability(up to 160℃ without noticeable deformation),and good flexibility even at a high ceramics content(66.7 wt%).Large-area selfstanding film can be obtained by a facile coating route.The electrolyte/electrode interface can be further enhanced via forming a soft interface by in-situ polymerization.Quasi-solid-state Li|D-CSE|LiCoO_(2)coin cells with the cathode-supported D-CSE can deliver a high initial discharge capacity of 134 mAh g^(-1) and a high capacity retention of 83%after 200 cycles at 0.5 C and 60℃.Quasi-solid-state Li|D-CSE|LiCoO_(2)pouch cells(designed capacity 8.6 mAh)with the self-standing D-CSE have a high retention of80%after 180 cycles at 2 mA charge and 4 mA discharge.At a high cathode loading(19.1 mg cm^(-2)),the Li|D-CSE|LiCoO_(2)pouch cell still can be stably cycled,and can withstand abuse tests of folding,cutting and nail penetration,indicating practical applications of the D-CSE.

Poly(imine-amide)Hybrid Covalent Adaptable Networks via in situ Oxidation Polymerization

Polyimine represents a rapidly emerging class of readily accessible and affordable covalent adaptable networks(CANs)that have been extensively studied in the past few years.While being highly malleable and recyclable,the pioneering polyimine materials are relatively soft and not suitable for certain applications that require high mechanical performance.Recent studies have demonstrated the possibility of significantly improving polyimine properties by varying its monomer building blocks,but such component variations are usually not straightforward and can be potentially challenging and costly.Herein,we report an in situ oxidation polymerization strategy for preparation of mechanically strong poly(imine-amide)(PIA)hybrid CANs from simple amine and aldehyde monomers.By converting a portion of reversible imine bonds into high-strength amide linkages in situ,the obtained hybrid materials exhibit gradually improved Young’s modulus and ultimate tensile strength as the oxidation level increased.Meanwhile,the PIAs remain reprocessable and can be depolymerized into small molecules and oligomers similar as polyimine.This work demonstrates the great potential of the in situ transformation strategy as a new approach for development of various mechanically tunable CANs from the same starting building blocks.

Preparation and Properties of pH-Responsive Intelligent Medical Dressing Based on Bacterial Cellulose/Polyacrylic Acid

Bacterial cellulose/polyacrylic acid (BC/PAA) pH-responsive hydrogels were prepared by free-radical polymerization (in situ) using BC as the raw material and AA as the monomer. The hydrogels were loaded with curcumin (Cur) to prepare pH-responsive intelligent medical dressings. The preparation process of the hydrogels was optimized by a single factor and response surface experiment using their swelling degree as an index. The structures of BC/PAA pH-responsive hydrogels were characterized by scanning electron microscope (SEM), Fourier Transform Infrared spectrometer (FTIR), X-ray diffraction (XRD), and tensile tester, and the swelling properties, mechanical properties, bacteriostatic properties, and drug release behavior were investigated. The results showed that the BC/PAA pH-responsive hydrogel has a three-dimensional network structure with the swelling rate up to 1600 g/g, compressive strength of up to 8 KPa, and good mechanical properties, and the drug release behavior was in line with the logistic dynamics model, and it has good inhibitory effects on common pathogens of wound infection: E. coli, S. aureus, and P. aeruginosa.

Advances in advanced solution-synthesis-based structural materials for tactile sensors and their intelligent applications

Intelligent applications,with tactile sensors at their core,represent significant advancement in the field of artificial intelligence.However,achieving perception abilities in tactile sensors that match or exceed human skin remains a formidable challenge.Consequently,the design and implementation of hierarchical structural materials are considered the optimal solution to this challenge.In contrast to conventional methods,such as complicated lithography and three-dimensional printing,the cost-effective and scalable nature of advanced solution-synthesis methods makes them ideal for preparing diverse tactile sensors with hierarchical structural materials.However,the process and applicability of advanced solution synthesis methods have yet to form a seamless system.Accordingly,the development and intellectualization of tactile sensors based on advanced solution synthesis methods are still in their early stages,and require a comprehensive and systematic review to usher in progress.This study delves into the advantages and disadvantages of various advanced solution synthesis methods,providing detailed insights.Furthermore,the positive effects of hierarchical structural materials constructed using these methods in tactile sensors and their intelligent applications are also discussed in depth.Finally,the challenges and future opportunities faced by this emerging field are summarized.

Stabilizing the Extrinsic Porosity in Metal-Organic Cages-Based Supramolecular Framework by In Situ Catalytic Polymerization

Porous supramolecular frameworks based on metal-organic cages(MOCs)usually have poor structural stability after activation.This issue narrows the scope of their potential applications,particularly for the inclusion of guest molecules that demand high porosity.Herein,the authors have reported the stabilization of a mesoporous zirconium MOC-based supramolecular framework with an in situ catalytic polymerization strategy.Due to the passivation effect imparted by this strategy,the introduced polymer is primarily distributed on the surface of the crystals,which results in the hybrid material retaining its crystallinity and permanent porosity.A preliminary application of this type of stabilized mesoporous supramolecular framework shows that among MOC-based supramolecular frameworks,it has the highest high-pressure methane uptake.Such a facile strategy may provide a general way to stabilize fragile porous materials and facilitate exploration of their potential applications.

Cement mortar with enhanced flexural strength and durability-related properties using in situ polymerized interpenetration network

ABSTRACT The low flexural strength and high brittleness of cementitious materials impair their service life in building structures.In this study,we developed a new polymer-modified mortar by in situ polymerization of acrylamide(AM)monomers during the cement setting,which enhanced the flexural and durable performances of mortars.The mechanical properties,micro-and-pore structures,hydrated products,interactions between cement hydrates and polyacrylamide(PAM),and durability-related properties of the mortars were investigated comprehensively.Mortars with 5%PAM exhibited the best performance in terms of flexural strength among all the mixtures.The mechanical strength of cement pastes modified by in situ polymerization of AM monomers was significantly superior to those modified by PAM.The chemical interactions between the polymer molecules and cement hydrates together with the formation of polymer films glued the cement hydrates and polymers and resulted in an interpenetrating network structure,which strengthened the flexural strength.Reductions in porosity and calcium hydroxide content and improvement in capillary water absorption were achieved with the addition of PAM.Finally,the chloride resistance was significantly enhanced with the incorporation of PAM.

In Situ Copolymerizated Gel Polymer Electrolyte with Cross-Linked Network for Sodium-Ion Batteries

High thermal stability,nonflammability,and no liquid leakage are indispensable capabilities for electrolytes in sodium-ion batteries toward large-scale energy storage systems.The use of solid-state or gel polymer electrolytes has proven to be one of the enabling tools to bring about these advancements;however,their application suffer from tedious synthesis procedure and/or lowionic transport to ensure a battery operation.Herein,a novel gel polymer electrolyte with a cross-linked polyether network(GPE-CPN)was crafted through a self-catalyzed strategy,where in situ copolymerization of two monomers,1,3-dioxolane and trimethylolpropane triglycidyl ether is realized successfully,with the use of sodium hexafluorophosphate(NaPF_(6))as an initiator,at room temperature.We demonstrate that the resultant GPE-CPN possesses a superior electrochemical stability window up to 4 V versus Na^(+)/Na,a considerable ionic conductivity,of 8.2×10^(−4)S cm^(−1) at room temperature,which is a capability good enough to suppress the growth of sodium dendrites and thus,stabilize the interface of electrolyte/sodium anode.Considering the benefit from its facile fabrication and superior characteristics,the asgenerated GPE-CPN reveals a potential application for future rechargeable sodium batteries.

Stabilizing the Electrochemistry of Lithium-Selenium Battery via In situ Gelated Polymer Electrolyte: A Look from Anode

Li metal possesses a high theoretical specific capacity,high electronic conductivity,and a low electrochemical potential,making it a promising anode material for building next-generation rechargeable metal batteries.In case conventional liquid electrolytes were used,and the anode using Li metal has been hindered by unstable(electro)chemistry at Li/electrolyte interface and the accompanied dendrite issue.Specifically,for the Li-Se batteries,the dissolution and shuttle of polyselenide intermediates lead to the deposition of poorly-conductive species on the anode,which further aggravates the chemical environment at the anode.In this work,we proposed to stabilize the Li-Se electrochemistry by constructing a gel polymer electrolyte via in situ gelations of conventional ether-based electrolytes at room temperature.The results demonstrate that the in situ gelated electrolyte helps to build electrochemically stable electrode/electrolyte interfaces and promote the efficient transfer of charge carriers across the interface.Compared with the liquid electrolytes,the gelated electrolyte shows improved chemical compatibility with the Li metal anode,which effectively alleviates the unfavorable side reactions and dendrite formation at the anode/electrolyte interface,and the polyselenide shuttle from the cathode to the anode.As a result,the Li-Se battery shows a higher Coulombic efficiency and improved cycling performance.

Novel Quasi Solid-State Succinonitrile-based Electrolyte with Low-flammability for Lithium-ion Battery

Quasi solid-state succinonitrile(SN)-based polymer electrolytes have emerged for lithium-metal batteries due to their excellent ionconductivity at room temperature,wide electrochemical stability window(ESW,usually>5 V).However,the practical application of these solid SN-based polymer electrolytes is hampered by the flammability and the inherent instability of SN to Li-metal anode.In this work,solid SN-based polymer electrolytes were prepared with succinonitrile,ethoxylated trimethylolpropane triacrylate(ETPTA),triethyl phosphate(TEP)and fluoroethylene carbonate for Li-metal battery via in situ polymerization method.The SN-based polymer electrolytes with 5 wt%triethyl phosphate and FEC showed good nonflammability,superior ion-conductivity as high as 1.01×10^(-3)S/cm,and wide ESW of 5.41 V.This SN-based polymer electrolyte also exhibited excellent interfacial compatibility to lithium metal anode.And it also delivered a high specific capacity of 156m Ah/g at 0.2 C at ambient temperature,and presented stable cycling at 1.0 C with a specific capacity retention of 98.4%after 1000 cycles.This work provides an alternative and simple strategy to realize the practical application of the solid-state SN-based polymer electrolyte.

A nano fiber–gel composite electrolyte with high Li^(+) transference number for application in quasi-solid batteries

As their Liþtransference number(tLiþ),ionic conductivity,and safety are all high,polymer electrolytes play a vital role in overcoming uncontrollable lithium dendrites and low energy density in Li metal batteries(LMBs).We therefore synthesized a three-dimensional(3D)semi-interpenetrating network-based single-ion-conducting fiber–gel composite polymer electrolyte(FGCPE)via an electrospinning,initiation,and in situ polymerization method.The FGCPE provides high ionic conductivity(1.36 mS cm^(-1)),high t_(Li+)(0.92),and a high electrochemical stability window(up to 4.84 V).More importantly,the aromatic heterocyclic structure of the biphenyl in the nanofiber membrane promotes the carbonization of the system(the limiting oxygen index value of the nanofiber membrane reaches 41%),giving it certain flame-retardant properties and solving the source-material safety issue.Due to the in situ method,the observable physical interface between electrodes and electrolytes is virtually eliminated,yielding a compact whole that facilitates rapid kinetic reactions in the cell.More excitingly,the LFP/FGCPE/Li cell displays outstanding cycling stability,with a capacity retention of 91.6%for 500 cycles even at 10C.We also test the FGCPE in high-voltage NMC532/FGCPE/Li cells and pouch cells.This newly designed FGCPE exhibits superior potential and feasibility for promoting the development of LMBs with high energy density and safety.