Composite Thin Films Research Articles

Enhanced charge separation at the interface of Cu2O/CuSCN composite thin films synthesized by electrodeposition technique

This study focuses on the synthesis and characterization of hole transport layers (HTLs) for solar cells, par- ticularly copper(I) thiocyanate (CuSCN) and cuprous oxide (Cu2O), synthesized via electrodeposition tech- niques. CuSCN and Cu2O offer promising properties for efficient charge transport in photovoltaic devices. The synthesis processes involve precise control of deposition parameters to achieve desired film morpholo- gies and properties. Characterization techniques including scanning electron microscopy (SEM), atomic force microscopy (AFM), and ultraviolet-visible (UV-Vis) spectroscopy provide insights into film morphology and optical properties. Optimization of synthesis parameters for Cu2O films is explored to enhance their electrical properties. Photoelectric response measurements indicate improved charge separation at the interface of Cu2O/CuSCN composite films. These findings can contribute to the advancement of solar cell technology. Furthermore, the study extends its exploration to the fabrication of Cu2O by electrodeposition at different pH levels. SEM and X-ray diffraction (XRD) analyses reveal the impact of deposition parameters on film mor- phology and crystal structure, providing valuable insights for tailored synthesis approaches. Overall, this comprehensive study not only advances the understanding of HTL materials synthesis and optimization but also provides valuable guidance for the development of high-efficiency and stable solar cell devices.

Thin-film composite nanofiltration membrane based on polysulfonamide for extremely acidic conditions

Increasing the acid stability and selectivity of nanofiltration (NF) membranes, which are used to treat acidic industrial effluents, is highly beneficial. A series of acid-stable NF membranes featuring polysulfonamide (PSA) separation layers were prepared through interfacial polymerization of branched polyethyleneimine (PEI), polyethylenepolyamine (PPA), and 1,3-benzenedisulfonyl chloride (BDSC) on a porous polyethersulfone (PES) substrate. The optimization of the membrane filtration performance involved analyzing the monomer content in both the aqueous and organic phases and adjusting the PEI-to-PPA ratio, thereby preparing ultrathin PSA layers. The influence of the PSA morphology and structure on the membrane filtration performance was examined. The most effectively optimized sample demonstrated a MgSO4 rejection rate of 95.4 ± 0.4 % and a water flux of 55.4 ± 1 L m–2h−1 at a pressure of 2.0 MPa. The acid stability of the membrane was assessed by examining the permeation, separation, and physicochemical properties before and after undergoing static acid-soaking tests. Following a 5-month exposure to 20 % (w/v) HCl or 20 % (w/v) H2SO4 aqueous solution, the optimal membrane maintained a MgSO4 rejection of 92.6 % at neutral pH, with a permeation flux of 68.2 L m–2h−1 under 2.0 MPa. Owing to their excellent selectivity, enhanced acid stability, structural controllability, and ease of functionalization, these PSA-NF membranes are promising for use in industries such as mining, semiconductor, and electroplating.

Innovative temperature-responsive membrane with an elastic interface for biofouling mitigation in industrial circulating cooling water treatment

To address the issues of scaling caused by heat and water evaporation in regard to circulating cooling water (CCW), TFC membrane filtration systems have been increasingly considered for terminal treatment processes because of their excellent separation performance. However, membrane biofouling phenomenon significantly hinders the widespread utilization of TFC membranes. In this study, to harness the thermal phenomenon of CCW and establish a stable and durable multifunctional antibiofouling layer, temperature-responsive Pnipam and the spectral antibacterial agent Ag were organically incorporated into commercially available TFC membranes. Biological experimental findings demonstrated that above the lower critical solution temperature (LCST), the contraction of Pnipam molecular chains facilitated the inactivation of bacteria by the antibacterial agent, resulting in an impressive sterilization efficiency of up to 99 %. XDLVO analysis revealed that below the LCST, the establishment of a hydration layer on the functional interface resulted in the creation of elevated energy barriers, effectively impeding bacterial adhesion to the membrane surface. Consequently, a high bacterial release rate of 98.4 % was achieved on the low-temperature surface. The alterations in the functional membrane surface conformation induced by temperature variations further amplified the separation between the pollutants and the membrane, creating an enhanced "elastic interface." This efficient and straightforward cleaning procedure mitigated the formation of irreversible fouling without compromising the integrity of the membrane surface. This study presents a deliberately engineered thermoresponsive antibiofouling membrane interface to address the issue of membrane fouling in membrane-based CCW treatment systems while shedding new light on the mechanisms of "inactivation" and "defense."

Comprehensive analysis of chemical composition, electronic, luminescent, and electrical properties of amorphous graphite-silicon carbide thin films: A comparative study of as-deposited and post-annealed states

Graphite/SiC (GSC) thin films were synthesized on silicon substrates via a spray method, depositing a Si-graphite solution on preheated silicon samples at 350 °C, followed by annealing at 800 °C for 4 h. A systematic approach was employed to ensure the effective incorporation of graphite into the SiC material during solution preparation. Various analytical techniques, including XPS, UPS, Reflection Energy Electron Loss Spectroscopy (REELS), PL, AFM, and Hall effect measurements, were employed for comparative analysis of the chemical composition, morphological, electrical, and optoelectronic properties of as-deposited and annealed GSC films. XPS analysis revealed the presence of Si—C and graphitic bonds in the as-deposited GSC, with a significant compositional shift to oxygen-rich graphite oxide/oxycarbides after annealing. REELS demonstrated increased bandgap and bulk plasmon energy due to surface oxidation, while UPS highlighted a high electronic density in the as-deposited film, diminishing after annealing. AFM revealed a tendency of as-deposited GSC grains to form smaller, sharper structures after annealing, resulting in smoother and more homogeneous surface morphology. Phase AFM confirmed graphite incorporation at grain boundaries and within the bulk, forming a composite structure. PL spectra of the as-deposited film exhibited a broad visible emission with distinct sub-peaks linked to SiC bandgap transitions and carbon-rich defects. Chromaticity diagrams indicated suitability for white LED applications. Hall effect measurements showed excellent electrical properties of the as-deposited GSC film, with high carrier density and mobility, which reduced significantly after annealing, transitioning the material to a more insulating state. These findings collectively provide a comprehensive understanding of GSC thin films’ properties and their potential applications.

Electronic, electrical and magnetic behavioural changes of layer by layer deposited Cd0.4Zn0.6S and r-GO composites thin film (Cd0.4Zn0.6S:r-GO) semiconductors

Electronic, electrical and magnetic behavioural changes of layer by layer deposited Cd0.4Zn0.6S and r-GO composites thin film (Cd0.4Zn0.6S:r-GO) semiconductors

Protonated polyethyleneimine enables synchronous crosslinking of polyimide nanofiltration membranes for dye desalination

Dye recovery and desalination are of great significance in the treatment of printing and dyeing wastewater. Nanofiltration (NF) has been proved an effective method for dye desalination. As organic solvents are usually coexisted, there is a great demand for organic solvent nanofiltration (OSN) membranes. Compared to thin film composite (TFC) membranes prepared by interfacial polymerized (IP), integrally skinned asymmetric (ISA) membranes with relatively thicker selective layer may present better separation stability in harsh solvent and cleaning reagent. In this work, polyethyleneimine-b-polyethersulfone (PEI-PES) is synthesized and added to PI solution directly, the crosslinking reaction proceeds along with phase conversion process. The PEI chains endow the membrane with good hydrophilicity and high positive charge. PEI-PES/PI membranes show stable permeability in organic solvents such as N, N-dimethylformamide (DMF), ethanol (EtOH) and toluene, etc. The rejections of dyes such as Congo Red (CR), Janus Green B, and Sunset Yellow are over 95 % in EtOH, while the rejections of salts like MgSO4 and Na2SO4 are around 20 %. After 200 h separation test, the rejection for CR remains around 92 % in DMF and 96 % in EtOH with a stable flux. The simple and cost-effective preparation process can accelerate the progress of the positively charged OSN membranes.

Boosting deep-ultraviolet photodetector performance via ferroelectric effect based on HfAlOx@PEI composite

In this study, hafnium-aluminum oxide (HfAlOx) was used as an effective active layer in a self-powered deep-ultraviolet (UV) photodetector. For the first time, we exploited the ferroelectric properties of crystalline HfAlOx to enhance device performance. The HfAlOx powder obtained at an annealing temperature of 850 °C exhibited the highest-intensity peak for the orthorhombic phase (o-phase), representing the ferroelectric property of the material. The HfAlOx particles were reduced to a small size using mechanical treatment to facilitate the preparation of a composite thin film with a polyethyleneimine (PEI) polymer matrix. First, the HfAlOx@PEI composite film-based photodetector demonstrated a remarkable on/off ratio of more than 103 and a rapid response (trise/tfall of 0.127/2.7 s) at zero bias under 254-nm UV illumination. Second, the photocurrent of the device was dramatically boosted under an external bias owing to the injection of carriers, supported by the ferroelectric effect of the o-phase HfAlOx. As a result, the external quantum efficiency and responsivity approached 2628 % and 5.37 A/W at −1 V bias, respectively. Furthermore, the device exhibited excellent photostability, demonstrating almost no change in the photocurrent after 1000 s of UVC irradiation. Our findings provide guidance for the preparation of optoelectronic devices, particularly self-powered high-performance UV photodetectors.

Advanced lithium extraction nanofiltration membrane with fast transport channels via competitive diffusion and reaction of rigid electropositive phenylbiguanide molecules

The utilization of nanofiltration membranes for lithium extraction from Salt-Lake holds the potential to address lithium resource scarcity and drive energy transformation. Nevertheless, the trade-off effect between water permeability and Mg2+/Li+ separation selectivity poses a challenge in the application of these membranes. In this work, rigid-flexible interpenetration and competitive diffusion reaction strategies were proposed to regulate the pore structure and charge density of the functional layer, thus enhancing the overall separation performance of nanofiltration membrane. Phenylbiguanide (PBG) possessing rigid structure, high positive charge density, and low energy transfer barrier was embedded into flexible polyethyleneimine-based polyamide network. This integration facilitated the formation of continuous and semi-permanent microcavities with rigid-flexible coupled structure, and meanwhile, elevated the density of positive charges. Consequently, the modification extended the water molecular transport channels within the functional layer, leading to a notable enhancement in pure water flux, from 7.40 to 26.43 L m−2h−1. In addition, due to the faster diffusion of PBG than polyethyleneimine with high molecular weight (70000 Da, as aqueous monomer in this work), it could react with excess 1,3,5-trimesoyl chloride (TMC) on the surface of initial membrane to form a new polyamide layer, which repaired the defects in the functional layer and also enhanced the charge density inside pore channels. Therefore, Mg2+/Li+ separation selectivity factor increased from 3.79 of TFC membrane to 22.98 of PBG membrane, i.e., by about 6 times. This study provided an effective strategy to develop nanofiltration membranes with both good water permeability and Mg2+/Li+ selectivity.

Preparation and Characterization of EVAc/ TiO2 Nanocomposites Coating for Oil Pipes Protection

The spin coating process was used in this study to create nanocomposites of ethynevinyl acetate copolymer reinforced with nano titania nanoparticles at various ratios (50, 100, & 150 part/million). Using Fourier-transform infrared spectroscopy (FTIR), different types of reactions between TiO2 and EVAc were investigated. Deferential Scanning Calorimetry was used to study melting point of thin films. As well as , anti corrosion resistance of thin films using electrochemical method were studied Results show that the adding of TiO2 nanoparticles enhanced the thermal characteristics of nano composite thin films, Tm increasing from 66 oC to 71 oC, The results of the FTIR analysis demonstrate that the nanoscale TiO2 and EVAc are physically reacting. Anti-corrosion behavior shows that the corrosion current reduces from 188 mA to 1 nA and corrosion resistance was increased. Additionally, the efficacy of inhibition increased from 0.0 to 99%. with adding Nano TiO2 with 150 ppm to thin films.

Controllable Design of Polyamide Composite Membrane Separation Layer Structures via Metal-Organic Frameworks: A Review.

Optimizing the structure of the polyamide (PA) layer to improve the separation performance of PA thin-film composite (TFC) membranes has always been a hot topic in the field of membrane preparation. As novel crystalline materials with high porosity, multi-functional groups, and good compatibility with membrane substrate, metal-organic frameworks (MOFs) have been introduced in the past decade for the modification of the PA structure in order to break through the separation trade-off between permeability and selectivity. This review begins by summarizing the recent progress in the control of MOF-based thin-film nanocomposite (TFN) membrane structures. The review also covers different strategies used for preparing TFN membranes. Additionally, it discusses the mechanisms behind how these strategies regulate the structure and properties of PA. Finally, the design of a competent MOF material that is suitable to reach the requirements for the fabrication of TFN membranes is also discussed. The aim of this paper is to provide key insights into the precise control of TFN-PA structures based on MOFs.

Tailoring thin film composite membranes for enhanced removal of heavy metals from water

Tailoring thin film composite membranes for enhanced removal of heavy metals from water

3D printed microcrystalline CsI:Tl composite scintillating thin films for X-ray imaging

The utilization of additive manufacturing techniques, especially Digital Light Printing (DLP), in fabricating CsI:Tl scintillator films demonstrates considerable potential for streamlining the production of scintillators tailored for X-ray imaging applications. This research focuses on the fabrication of CsI:Tl-based composite plastic scintillator thin films. In this study, circular films measuring 1-inch in diameter and 0.1 mm & 0.2 mm in thickness are being produced and tested for gamma photon counts under alpha and gamma radiation. To establish the stopping power range of the films, a Monte Carlo based GEANT4 simulation has been carried out. Additionally, investigations into their suitability for X-ray imaging applications are being conducted, revealing the spatial resolution of the films (0.2 and 0.1 mm) between 100 and 130 μm and 1.26 lp/mm with a contrast range of 4.0–12.3 %. The observed decrease in spatial resolution and contrast for the 0.2 mm thick film is attributed to the thickness increase exacerbating the scattering phenomenon while simultaneously enhancing the X-ray stopping power. This highlights the significance of inherent trade-off between maximizing spatial resolution and compromising light yield of 0.1 mm films compared to the 0.2 mm thick film. By utilizing 3D printing, this approach offers a cost-effective and time-efficient method for producing thin-film scintillators with enhanced flexibility and customization options compared to conventional methods.

Expanding interfacial polymerization for gas separation beyond water purification

Extending interfacial polymerization (IP) to gas separation is challenging due to microdefects in dry conditions, despite its attractive and straightforward processability. This study presents a systematic defect-tailoring approach for highly reproducible polyamide (PA) thin film composite (TFC) membranes with precise size-sieving ability. The approach combines highly porous polyethylene support, extended IP reaction time (60 min), and post-thermal/solvent treatments, resulting in a homogeneous PA selective layer. Particularly, isopropanol treatment removes less-reacted amine-rich monomers/oligomers and promotes PA network chain relaxation, enhancing molecular-sieving capability. The resulting PA TFC membrane exhibits a remarkable H2/CO2 selectivity of 24.8 (±3.1) and an H2 permeance of 13.6 (±1.8) gas permeation unit, surpassing the polymeric upper bound. It also ensures mechanical stability under high feed pressure and resistance to physical aging, highlighting its robustness. Additionally, universality is validated using different amine monomers. This systematic method provides a valuable framework for producing reproducible PA TFC membranes with exceptional gas separation performance, enabling practical implementation across industrial sectors.

High permeance of polyamide nanofiltration membranes with porous organic polymers interlayers based on diazo coupling reaction

Nanofiltration (NF) membranes are widely used in many fields, including food, petrochemical and brackish water desalination. One of the challenges for preparing NF membranes is to make NF membranes with high both permeability and selectivity because of the “trade-off" effect. To weaken or break through the “trade-off" effect, the thin film composite (TFC) NF membranes with high permeability and selectivity were prepared by constructing porous organic polymers (POPs) interlayers via diazo coupling reaction in the wild condition. The effects of the monomers ratio used to prepare POPs interlayers on the separation performance of the as-prepared TFC NF membranes as well as on the surface characteristics of substrate and polyamide (PA) separation layer were investigated. Due to hydrogen bonding, the POPs interlayers with hydroxyl groups slow down the diffusion rate of PIP molecules, which changes the surface structure of the polyamide (PA) separation layer from the nodular structure to the folded structure that favors increased permeability. The pure water permeance of the optimal TFC-S4 membrane (47.5 ± 0.3 L m−2 h−1 bar−1) is 3.8 times higher than that of the commercial polyamide nanofiltration membrane NF270 (12.5 L m−2 h−1 bar−1). Na2SO4 rejection of the TFC-S4 membrane is 98.7 ± 0.1 %, which is greater than that of NF270 (96 %). This study provides ideas for future applications of POPs materials in NF membranes desalination.

Polyamide nanofiltration membrane modified with defective covalent organic framework interlayer for selective ion sieving

Generally, thin-film composite (TFC) membranes prepared using piperazine (PIP) and trimesoyl chloride (TMC) exhibit good Na2SO4 rejection, but their MgCl2 rejection is not satisfactory. In this study, a defective covalent organic framework (COF) interlayer with residual unreacted amine groups was fabricated via interfacial polymerization (IP) by changing the catalyst concentration. Introduction of the COF layer into a polyamide (PA) separation membrane modified the pore size of the PA layer, thereby improving the rejection of divalent cations. The pore size of the PA layer decreased and the surface morphology of the membrane was converted from nodular to a hybrid morphology of “ridge-and-valleys’’ and nodules, indicating that the residual unreacted amine groups on the COF interlayer successfully reacted with the acyl chloride groups. The optimal membrane (PIP/COF-A/PES) exhibited high rejection of divalent ions (Na2SO4 of 98.3% and MgCl2 of 94.3%), and the membrane showed excellent capability for separating mono/divalent ions. Overall, a method of preparing nanofiltration membranes by modifying the PA layer to enhance the rejection of divalent cations was demonstrated.

Facile fabrication of robust and tight PIMs-based TFC hollow fiber membranes with a semi-interpenetrating polymer network via liquid phase cross-linking for organic solvent nanofiltration

Resource recovery and reuse are essential for sustainable development, particularly for high-value resources such as homogeneous (photo)catalysts, active pharmaceutical ingredients, and high-value natural compounds, which can offer economic benefits. Recently, organic solvent nanofiltration (OSN) for resource recovery has gained significant attention owing to its advantages including low energy consumption and seamless integration with other processes. Polymers of intrinsic microporosity (PIMs) have great potential as membrane materials for OSN, owing to their excellent pore properties and solution processability. However, swelling and dissolution of PIMs in organic solvents can impede the filtration performance of PIMs-based OSN membranes. In this study, we fabricated thin-film composite hollow fiber membranes for OSN based on PIMs with improved organic solvent stability using a semi-interpenetrating polymer network (semi-IPN) formed by cross-linking Matrimid with 1,6-hexanediamine within the PIMs through the liquid phase cross-linking method. Semi-IPNs mitigate swelling and tighten the pores of PIMs-based membranes, enabling excellent filtration and molecular separation performance. Furthermore, the fabricated PIMs with a semi-IPN membrane exhibited excellent rejection performance (>96 %) for homogeneous photocatalysts, allowing successful concentration and recovery via OSN. Therefore, PIMs-based membranes with a semi-IPN hold great promise as OSN membranes for the recovery of valuable resources.

Charge mediated nano-filtration for recovering sinapic acid from a mustard bran hydrolysate

The recovery of valuable chemicals, such as sinapic acid, from enzymatic hydrolysates is essential to enabling a sustainable biorefinery. In this study, we designed a system to recover sinapic acid produced chemo-enzymatically from waste mustard bran. The process involves sequential separation, beginning with size partitioning using ultrafiltration for enzyme removal and recovery, followed by charge-mediated size partitioning via nanofiltration to isolate sinapic acid from other extracts. Four polyethersulfone (PES) ultrafiltration membranes with molecular weight cut-offs (MWCOs) of 5000 and 10 000 Da and maximum allowable working pressures (MAWPs) of 3 and 10 bar were screened for their effectiveness in removing Bovine Serum Albumin (BSA) as a model compound. Subsequently, these membranes were applied to recover the feruloyl esterase enzyme. The membrane with an MWCO of 5000 Da and an MAWP of 10 bar achieved 97.93 % enzyme recovery with a permeate flow rate of 31.4 L/h/m2 at 6 bar. Next, we evaluated the effects of zeta potential interactions on the preferential rejection of sinapic acid using various nanofiltration membranes with potentially charged surfaces, including polyimide, silicon-based thin film composite, and polypiperazine amide membranes with MWCOs ranging from 150 to 600 Da. The polypiperazine amide membrane demonstrated the highest recovery of sinapic acid, achieving 86 % recovery from a model solution and 64 % recovery from mustard bran hydrolysate. Compositional analysis of the permeate confirmed that the rejection rate (R) is influenced primarily by the pKa rather than molecular size, following the trend: sinapic acid (pKa = 4.58; 224.2 Da; R = 64.0 %), acetic acid (pKa = 4.76; 60.1 Da; R = 23.8 %), xylose (pKa = 12.15; 150.1 Da; R = 13.7 %), glucose (pKa = 12.28; 180.2 Da; R = 8.7 %), and arabinose (pKa = 12.34; 150.1 Da; R = 8.5 %). The zeta potential interactions across nanofiltration membranes enhanced sinapic acid recovery from the mustard bran hydrolysate, hence, charge mediation significantly influenced the membrane separation of these complex mixtures with varying pKa values.

Study of thin film composites based on LiCoO2 and C60 using neutron depth profiling and atomic force microscopy

Study of thin film composites based on LiCoO2 and C60 using neutron depth profiling and atomic force microscopy

Brine separation with polyamide and polyimine thin film composite nanofiltration membranes obtained from biobased monomers

Thin film composite (TFC) membranes are state-of-the-art membranes that are widely applied in water treatment and seawater desalination. However, these membranes are typically prepared using petrochemical-based monomers and toxic solvents. Herein, plant-based monomers, namely priamine (PA), 2,5-furandicarboxaldehyde (FDA) are used to fabricate green PA–FDA TFC membranes via interfacial polymerization. Additionally, PA was also combined with trimesoyl chloride (TMC) to obtain PA–TMC TFC membranes. The reaction conditions were varied to investigate their effects on membrane morphology and performance. The resultant membranes exhibited smooth surfaces with an average roughness ranging from 15 to 30 nm, and increasing the monomer concentration increased the film thickness. The PA–TMC free-standing films had higher thicknesses (130–300 nm) than the PA–FDA films (36–122 nm). Furthermore, PA–TMC and PA–FDA films were hydrophobic due to the long aliphatic chains of PA. Moreover, PA–TMC membranes demonstrated a water permeance of ∼4 L m−2 h−1 bar−1 with 74% NaCl rejection, while PA–FDA membranes achieved better NaCl rejection (∼80%) but lower water permeance (0.3–4 L m−2 h−1 bar−1). Applied in brine separation, the membranes demonstrated ∼90% divalent ion rejection and only 70% monovalent ion rejection. The proposed plant-based monomer combination provides a steppingstone toward green TFC membrane manufacturing for water treatment and desalination applications.

Asymmetric and mechanically enhanced MOF derived magnetic carbon-MXene/cellulose nanofiber films for electromagnetic interference shielding and electrothermal/photothermal conversion

The prosperity of wearable and microelectronic devices tremendously facilitates to exploit thin and flexible composite films with multifunction. Free-standing MXene films have aroused considerable interest in the fields of electromagnetic interference (EMI) shielding and thermal management because of brilliant electrical conductivity, distinctive layered architecture and remarkable localized surface plasmon resonance effect. Nevertheless, the inferior mechanical strength and potential performance degradation in humid environments seriously constrain their practical applications. In this regard, robust and multifunctional CoNi-MOF-74 derived magnetic carbon/cellulose nanofibers (CNF)-MXene/CNF composite films with Janus architecture were successfully constructed via two-step vacuum-assisted filtration technology. The rational arrangement of functional fillers effectively improves the impedance matching, promoting the incident electromagnetic waves to enter the films for consumption. Constructing double-layered structure could induce the generation of “absorption-reflection-reabsorption” dissipation manner, dramatically enhancing EMI shielding performance. The bi-layered magnetic carbon/CNF-MXene/CNF composite membranes (0.1 mm in thickness) realize a fascinating EMI shielding effectiveness of 68.86 dB and a superior absorption efficiency of 58.82 dB. Meanwhile, the brilliant conductivity and significant localized surface plasmon resonance effect of MXene/CNF layer endow the composite films with excellent electrothermal/photothermal conversion capability, greatly broadening application prospects. The steady temperature of the composite films is as high as 112.9 °C within 10 s under the low driven voltage of 3.0 V and the saturation temperature reaches up to 154.2 °C within 15 s at the light intensity of 1500 W/m2, respectively. Moreover, the plentiful hydrogen bonding interaction and compact interfacial combination jointly enable the composite films to possess robust mechanical flexibility, satisfying the demands in practice. This work supplies a prospective guidance for preparing flexible and multifunctional composite films with Janus architecture, revealing great application potential in wearable and microelectronic devices even under harsh conditions.