Zwitterionic Nanohydrogel Grafted PVDF Membranes with Comprehensive Antifouling Property and Superior Cycle Stability for Oil‐in‐Water Emulsion Separation

Fouling caused by oil and other pollutants is one of the most serious challenges for membranes used for oil/water separation. Aiming at improving the comprehensive antifouling property of membranes and thus achieving long‐term cyclic stability, it is reported in this work the design of a kind of zwitterionic nanosized hydrogels grafted poly(vinylidene fluoride) (PVDF) microfiltration membrane (ZNG‐g‐PVDF) with superior fouling‐tolerant property for oil‐in‐water emulsion separation. Sulfobetaine zwitterionic nanohydrogels with the diameter of ≈ 50 nm are synthesized by an inverse microemulsion polymerization process. They are then grafted onto the surface of PVDF microfiltration membrane, endowing the membrane a superhydrophilic and nearly zero oil adhesion property. This ZNG‐g‐PVDF membrane exhibits great tolerance and resistance to salts pH, especially an excellent antifouling property to oil‐in‐water emulsions containing various pollutants such as surfactants, proteins, and natural organic materials (e.g., humic acid). The comprehensive antifouling property of the membrane gives rise to the cyclic stability of the membrane greatly improved. A nearly 100% recovery ratio of permeating flux is achieved during several cycles of oil‐in‐water emulsion filtration. The ZNG‐g‐PVDF membrane shows great potential in treating practical oily wastewater containing complicated components in the effluent.     

Biomimetic and Superwettable Nanofibrous Skins for Highly Efficient Separation of Oil‐in‐Water Emulsions

Developing a feasible and efficient separation membrane for the purification of highly emulsified oily wastewater is of significance but challenging due to the critical limitations of low flux and serious membrane fouling. Herein, a biomimetic and superwettable nanofibrous skin on an electrospun fibrous membrane via a facile strategy of synchronous electrospraying and electrospinning is created. The obtained nanofibrous skin possesses a lotus‐leaf‐like micro/nanostructured surface with intriguing superhydrophilicity and underwater superoleophobicity, which are due to the synergistic effect of the hierarchical roughness and hydrophilic polymeric matrix. The ultrathin, high porosity, sub‐micrometer porous skin layer results in the composite nanofibrous membranes exhibiting superior performances for separating both highly emulsified surfactant‐free and surfactant‐stabilized oil‐in‐water emulsions. An ultrahigh permeation flux of up to 5152 L m^?2 h^?1 with a separation efficiency of >99.93% is obtained solely under the driving of gravity (≈1 kPa), which was one order of magnitude higher than that of conventional filtration membranes with similar separation properties, showing significant applicability for energy‐saving filtration. Moreover, with the advantage of an excellent antioil fouling property, the membrane exhibits robust reusability for long‐term separation, which is promising for large‐scale oily wastewater remediation.     

A Bioinspired Capillary Force-Induced Driving Strategy for Constructing Ultra-Low-Pressure Separation Membranes

The development of low-pressure or pressureless self-driven membranes is important for saving energy and overcoming the critical trade-off effect in membrane separation processes. However, conventional self-driven membranes rely on gravity, which is effective in the separation of large-sized materials but is still ineffective in the fine separation of small molecules. Herein, inspired by the capillary effect that exists in nature, a capillary force-induced membrane-driving strategy for fine separation at ultra-low pressures is demonstrated. Hydrophilic nanoparticles are prepared by a cross-linking reaction between tannic acid and 3-aminopropyltriethoxysilane and then introduce them into membrane pores to simulate sand accumulation with an aim to generate the capillary force. The membrane is then used in ultra-low pressure membrane separation. Interestingly, it is found that the membrane has excellent performance in the separation of dye/salt mixtures (dye rejection > 99%, salt rejection < 10%) and a high permeate flux (160 L m⁻² h⁻¹) under near “zero pressure” conditions. Moreover, the structural stability of the membrane is verified. Introducing capillary forces into membranes as an autonomous driving force can be a promising universal approach that can be added up to the toolbox for the efficient preparation of separation membranes.     

A Lotus-Petiole-Inspired Hierarchical Design with Hydrophilic/Hydrophobic Management for Enhanced Solar Water Purification

Solar-driven vapor generation offers an affordable and sustainable approach to solve global freshwater scarcity. Creating interfacial solar evaporators capable of increasing water production rates matching human water requirements is highly desirable but challenging due to the slow water transportation dynamics and unavoidable oil-fouling. Herein, a bio-inspired lotus-petiole-mimetic microstructured graphene/poly(N-acryloyl glycinamide) solar evaporator with integrated hydrophilic and hydrophobic microregions is developed. Through accurate control of the supramolecular interactions, the optimized solar evaporator incorporating unique structural features and wettability shows high light harvesting, enhanced water activation, and reduced energy demand for water vaporization, enabling a groundbreaking comprehensive performance along evaporation rate up to 3.4 kg m⁻² h⁻¹ and energy conversion efficiency of ≈93% under one sun irradiation (1 kW m⁻²). Molecular dynamics simulations reveal that the abundant hydrogen bonding sites of the polymeric networks can thermodynamically modulate the escape behavior of water molecules. Notably, neither decrease in evaporation rate nor fouling on solar evaporators is observed during the prolonged purification process toward nano/submicrometer emulsions, oily brines, actual seawater, and domestic wastewater. This study provides distinctive insights into water evaporation behaviors at a molecular level and pioneers a rational strategy to design high-yield freshwater-generation systems for wastewater containing complex contaminants.     

A Floating Integrated Solar Micro-Evaporator for Self-Cleaning Desalination and Organic Degradation

Safe and clean freshwater harvesting from (organic-containing) saline or wastewater holds great potential for mitigating water scarcity and pollution, but remains challenging. Herein, a floating photothermal/catalytic-integrated interfacial micro-evaporator (g-C₃N₄@PANI/PS) is reported as a proof-of-concept multifunctional scavenger evaporator system (MSES) to achieve both solar-driven complete desalination and organic degradation. The spherical porous lightweight polystyrene core, incorporated with a black surface functional layer (g-C₃N₄@PANI), enables the hybrid micro-evaporator to naturally float and thereby collectively self-assemble under surface tension for interfacial evaporation, which achieves preeminent self-cleaning for complete salt/solute separation and efficient organic photodegradation under rotation. Remarkably, the floating micro-evaporator achieves a high solar-vapor conversion efficiency of ≈90% with high interfacial energy localization and provides abundant active photocatalytic sites on the interface, which is further enhanced by interfacial photothermal cooperation. High photo-driven degradation efficiencies of 99% for nonvolatile organic compounds (non-VOC) bisphenol A and 95% for VOC phenol in wastewater are achieved. An outdoor comprehensive solar water treatment test toward organic-containing high-salinity sewage verifies the feasibility of MSES for sustainable freshwater harvesting (1.3 kg m⁻² h⁻¹), downstream salt recovery, and organic degradation. This strategy may inspire an integrated solution of water scarcity, clean energy, and environmental pollution toward carbon neutrality.     

A Novel Multifunctional Photocatalytic Separation Membrane Based on Single-Component Seaweed-Like g-C3N4

Multifunctional separation membrane is usually realized by multi-component collaborative construction, which makes the membrane preparation method complicated and uncontrollable. Herein, a novel multifunctional photocatalytic separation membrane is prepared by vacuum self-assembly of single seaweed-like g-C₃N₄ photocatalyst. The seaweed-like g-C₃N₄ gives membrane certain roughness, large specific surface area, excellent hydrophilicity and abundant transport channels. Through a systematic study, the membrane exhibits excellent separation of five oil-in-water emulsions with a maximum flux of 3114.0 ± 113.0 L m⁻² h⁻¹ bar⁻¹ for 1, 2-dichloroethane-in-water (Dc/W) emulsion and a maximum efficiency of 97.4 ± 0.1% for chloroform-in-water (C/W) emulsion. In addition, the seaweed-like g-C₃N₄ with large specific surface area and narrow bandgap render excellent visible light absorption characteristics and accelerate e⁻-h⁺ pairs transport rate, giving the membrane excellent photocatalytic degradation and antibacterial properties. The membrane shows good degradation for eight different pollutants, among which the degradation effect for rhodamine B (RhB), methylene blue (MB), and crystal violet (CV) were ≈100%. The antibacterial efficiency against E. coli and S. aureus is also close to 100%. After 35 consecutive separations of C/W emulsion and 10 consecutive degradations of RhB, the membrane still maintains excellent separation performance. This long-lasting multifunctional separation membrane exhibits broad application prospects in complex wastewater purification.     

A Prussian-Blue Bifunctional Interface Membrane for Enhanced Flexible Al–Air Batteries

Flexible Al–air batteries have attracted widespread attention in the field of wearable power due to the high theoretical energy density of Al metal. However, the efficiency degradation and anodizing retardation caused by Al parasitic corrosion severely limit the performance breakthrough of the batteries. Herein, a Prussian-blue bifunctional interface membrane is proposed to improving the discharge performance of hydrogel-based Al–air battery. When a rational 12 mg·cm⁻² membrane is loaded, the effect of anticorrosion and activation is optimal thanks to the formation of a stable and breathable interface. The results demonstrate that a flexible Al–air battery using the membrane can output a high power density of 65.76 mW·cm⁻². Besides, the battery can achieve a high capacity of 2377.43 mAh·g⁻¹, anode efficiency of 79.78%, and energy density of 3176.39 Wh·kg⁻¹ at 10 mA·cm⁻². Density functional theory calculations uncover the anticorrosion-activation mechanism that Fe³⁺ with a large number of empty orbitals can accelerate electrons transfer, and nucleophilic reactant [Fe^II(CN)₆]⁴⁻ promotes the Al³⁺ diffusion. These findings are beneficial to the inhibition of interfacial parasitic corrosion and weakening of discharge hysteresis for flexible Al–air batteries.     

High-Efficiency Reactive Oxygen Species Generation by Multiphase and TiO6 Distortion-Mediated Superior Piezocatalysis in Perovskite Ferroelectrics

Piezocatalysis, governed by piezo-potential within piezoelectrics, has gained prominence for reactive oxygen species (ROS) generation, which is significant to environmental and biological applications. However, designing piezocatalysts with excellent piezocatalytic performance in a wide temperature and efficient charge carrier separation ability is still challenging. Herein, eco-friendly BaTiO₃ (BT)-based perovskite ferroelectrics with tailored multiphase coexistence in a wide temperature range are constructed to boost higher piezoelectricity and large piezo-potential, which is attributed to decreased polarization anisotropy by flat Gibbs energy profile. Elevated piezo-potential in designed BT-based piezocatalyst guarantees high-efficient generation rate of •OH (200 µmol g⁻¹ h⁻¹) and •O₂⁻ (40 µmol g⁻¹ h⁻¹) by ultrasound stimulation, which is 3.5 times more than that of pure BT. Besides, piezocatalytic capacity to degrade dye wastewater shows a rate constant of 0.0182 min⁻¹ and gives an antibacterial rate of 95% within 30 min for eliminating E. coli. Theoretical simulations validate that the local distortion of TiO₆ octahedra also contributes to piezocatalytic performance by inducing electron–hole pairs separation in real space, and better response to slight structural deformation. This work is important to design high-performance piezocatalysts with high-efficiency ROS generation for sewage treatment and sonodynamic therapy.     

A Nano-Heterogeneous Membrane for Efficient Separation of Lithium from High Magnesium/Lithium Ratio Brine

Lithium extraction from salt lake brines is highly demanded to circumvent the lithium supply shortage. However, polymer nanofiltration membranes suffer from low lithium permeability while nanofluidic devices are hindered by complicated preparation and miniaturized scales despite high permeability. Here, the authors report a facile strategy to prepare positively charged nanofiltration membranes for ultrapermeable and selective separation of lithium ions from concentrated magnesium/lithium mixtures. A new electrolyte monomer (diaminoethimidazole bromide, DAIB) containing bidentate amine groups is designed to modify pristine polyamide composite membranes. Structure characterizations and simulations show that the DAIB modification brings about nano-heterogeneity that not only improves surface hydrophilicity, but also reduces water transport resistance through the ≈100 nm thick separation layer. Water permeance of the modified membrane improves fivefold and is coupled with good stability in 200-h continuous nanofiltration. It exhibits high lithium flux (0.7 mol m⁻² h⁻¹) for brines (Mg²⁺/Li⁺ ratio 20) at 6 bar operation pressure.     

Ultraselective and Highly Permeable Polyamide Nanofilms for Ionic and Molecular Nanofiltration

Membranes with ultrahigh ion selectivity and high liquid permeance are needed to produce high-quality product water with increased recovery and process efficiency in water desalination. The narrow pore size distribution and controlled surface charge in the separation layer of nanofiltration membranes significantly improve the ion selectivity through molecular sieving and Donnan exclusion of co-ions. Here, the ultraselective and yet highly water permeable polyamide nanofilm composite nanofiltration membranes developed by precisely controlling the kinetics of the interfacial polymerization reaction by maintaining the stoichiometric equilibrium at the interface is reported. The kinetically favorable stoichiometric equilibrium condition prohibits the formation of aggregate pores in the nanofilm and leads to the formation of narrow network pores with a high surface negative charge. Nanofilms are designed with a controlled degree of crosslinking and made as thin as ≈7 nm to achieve increased water permeance. The ultraselective membranes exhibit up to 99.99% rejection of divalent salt (Na₂SO₄) and demonstrate monovalent to divalent ion selectivity of >4000. The selectivity of these nanofilm composite membranes is beyond the permeance–selectivity upper-bound line of the state-of-the-art nanofiltration membranes and one to two orders of magnitude higher than the commercially available membranes with pure water permeances of up to 23 L m⁻² h⁻¹ bar⁻¹. The fabrication process is scalable for membrane manufacturing.     

Engineering a Robust,Versatile Amphiphilic Membrane Surface Through Forced Surface Segregation for Ultralow Flux‐Decline

Unlike biofoulants/pollutants, oil foulants/pollutants are prone to coalesce, spread and migrate to form continuous fouling layer covering on the surfaces. Therefore, such kind of fouling can not be simply alleviated by hydrophilic modification with currently extensively used antifouling materials such as poly(ethylene glycol) (PEG)‐based or zwitterionic polymers etc. In the present study, an amphiphilic porous membrane surface, comprising hydrophilic fouling resistant domains and hydrophobic fouling release microdomains, is explored via a "forced surface segregation" approach. The resultant membranes exhibit both superior oil‐fouling and bio‐fouling resistant property: membrane fouling is exquisitely suppressed and the permeation flux‐decline is decreased to an ultralow level. It can be envisaged that the present study may open a novel avenue to the design and construction of robust, versatile antifouling surfaces.     

Electrospinning Synthesis of Self-Standing Cobalt/Nanocarbon Hybrid Membrane for Long-Life Rechargeable Zinc–Air Batteries

Integrating high-efficiency oxygen electrocatalyst directly into air electrodes is vital for zinc–air batteries to achieve higher electrochemical performance. Herein, a self-standing membrane composed of hierarchical cobalt/nanocarbon nanofibers is fabricated by the electrospinning technique. This hybrid membrane can be directly employed as the bifunctional air electrode in zinc–air batteries and can achieve a high peak power density of 304 mW cm⁻² with a long service life of 1500 h at 5 mA cm⁻². Its assembled solid-state zinc–air battery also delivers a promising power density of 176 mW cm⁻² with decent flexibility. The impressive rechargeable battery performance would be attributed to the self-standing membrane architecture integrated by oxygen electrocatalysts with abundant cobalt–nitrogen–carbon active species in the hierarchical electrode. This study may provide effective electrospinning solutions in integrating efficient electrocatalyst and electrode for energy storage and conversion technologies.     

3D-Printed Robust Dual Superlyophobic Ti-Based Porous Structure for Switchable Oil/Water Emulsion Separations

Smart surfaces with responsive wettability are unstable, and depend upon continuous external stimuli, which limits their widespread application in switchable oil/water emulsions separations. In this study, a Ti-based 3D porous structure (SLM-3DTi) is printed using advanced selective laser melting (SLM) technology for the switchable separation of oil/water emulsion. With the assistance of the computer program, porous structure and re-entrant texture can be easily designed and printed in one step. Without any continuous external stimulus, the wettability of SLM-3DTi can be reversibly switched between underwater superoleophobicity and underoil superhydrophobicity simply by drying and washing cycles. The SLM-3DTi achieves switchable surfactant-stabilized oil-in-water emulsion (SSE(o/w)) and surfactants-stabilized water-in-oil emulsion (SSE(w/o)) separation with purity above 99.8% at a flux of more than 2000 L m⁻² h⁻¹. In addition, the re-entrant texture of the SLM-3DTi surface is formed with the partially melting powder particles on the part contour, which has much stronger mechanical durability than any binder. Furthermore, SLM-3DTi has excellent corrosion resistance due to the material properties of Ti. More importantly, based on the visualization analysis of the simulation, the mechanism of SLM-3DTi emulsion separation is further elucidated. Therefore, SLM-3DTi has broad practical application potential for high-flux, high-purity, and switchable oil/water emulsion separation.     

N-CNTs-Based Composite Membrane Engineered By A Partially Embedded Strategy: A Facile Route To High-Performing Zinc-Based Flow Batteries

Zinc-based flow batteries are promising for distributed energy storage due to their low-cost and high-energy density advantages. One of the most critical issues for their practical application is the reliability that results from the heterogeneous zinc deposition and dead zinc from falling off the electrode. Herein, nitrogen-doped carbon nanotubes (N-CNTs)-based composite membrane through a facilely partially embedded method is reported to enable a dendrite-free alkaline zinc-based flow battery. The results indicate that the electrically conductive N-CNTs functional layer can enhance the transport dynamics of charge carriers and homogenize electric field distribution in membrane–electrode interface, which induces the initial nucleation of metallic zinc from the carbon felt electrode to N-CNTs functional layer and further achieve a uniform and dense plating of metallic zinc in alkaline media. Thus, the engineered membrane enables a stable alkaline zinc–iron flow battery performance for more than 350 h at a current density of 80 mA cm⁻². Moreover, an energy efficiency of over 80% can be afforded at a current density of 200 mA cm⁻². The scientific finding of this study provides a new strategy on composite membranes design and their capability to adjust the plating of metallic zinc in alkaline media.     

Biomimetic Hygroscopic Fibrous Membrane with Hierarchically Porous Structure for Rapid Atmospheric Water Harvesting

Sorption-based atmospheric water generation (SAWG) is a promising strategy to alleviate the drinkable water scarcity of arid regions. However, the high-water production efficiency remains challenging due to the sluggish sorption/desorption kinetics. Herein, a composite sorbent@biomimetic fibrous membrane (PPy-COF@Trilayer-LiCl) is reported by mimicking nature's Murray networks, which exhibits outstanding water uptake performance of 0.77–2.56 g g⁻¹ at a wide range of relative humidity of 30%–80% within 50 min and fast water release capacity of over 95% adsorbed water that can be released within 10 min under one sun irradiation. The superior sorption–desorption kinetics of PPy-COF@Trilayer-LiCl are enabled by the novel hierarchically porous structure, which is also the critical factor to lead a directional rapid water transport and vapor diffusion. Moreover, as a proof-of-concept demonstration, a wearable SAWG device is established, which can operate 10 sorption–desorption cycles per day in the outdoor condition and produce a high yield of clean water reaching up to 3.91 kg m⁻² day⁻¹. This study demonstrates a novel strategy for developing advanced solar-driven SAWG materials with efficient water sorption–desorption properties.     

In Situ Fabrication of Metal–Organic Framework Thin Films with Enhanced Pervaporation Performance

The intrinsic porosity in the periodic structures of metal–organic frameworks (MOFs) endows them with a great potential for membrane separation. However, facile fabrication of crystalline MOF membranes has been challenging and limited to few materials for economic and environmental considerations. Herein, a continuous Zr-MOF thin film with a thickness of ≈180 nm has been fabricated via in situ recrystallization of MOF nanoparticles on the porous support under formic acid vapor. Owing to the inherent microporosity and the well-established hydrophilicity during membrane fabrication, the MOF thin films exhibit excellent pervaporation performance with separation factors of 2630, 501 and fluxes of 1.45, 1.41 kg m⁻² h⁻¹) for n-butanol dehydration and methanol/methyl tert-butyl ether (MeOH/MTBE) separation, respectively. The structural stability of the film has been further confirmed by its steady performance in the 10-day pervaporation test. This in situ recrystallization method induced by a trace amount of acid vapor with no extra ingredients opens a new avenue for the facile membrane fabrication of various MOF materials to feasibly realize their versatile potential as membrane materials.     

Efficient Water Splitting System Enabled by Multifunctional Platinum-Free Electrocatalysts

Tremendous research efforts have been focused on the development of a water splitting system (WSS) to harvest hydrogen fuels, but currently available WSSs are complicated and cost-ineffective mainly due to the applications of noble platinum or different electrocatalysts. Herein, a novel WSS comprising electricity generation from solar panels, electricity storage in rechargeable zinc–air batteries (ZABs), and water splitting in electrolyzers, enabled by hybrid cobalt nanoparticles/N-doped carbon embellished on carbon cloth (Co–NC@CC) as multifunctional platinum-free electrocatalysts is reported. Consequently, the Co–NC@CC electrode presents excellent trifunctional electrocatalytic activity with an onset potential of 0.94 V for oxygen reduction reaction, and an overpotential of 240 and 73 mV to achieve a current density of 10 mA cm⁻² for oxygen and hydrogen evolution reactions, respectively. For a proof-of-concept application, a rechargeable ZAB assembled from the high-performance Co–NC@CC air cathode exhibits a high open circuit potential of 1.63 V and a superior energy density of 1051 Wh kg⁻¹_Zn. Furthermore, an overall water splitting electrolyzer constructed by the symmetrical Co–NC@CC electrodes delivers a current density of 10 mA cm⁻² at a low cell voltage of 1.57 V. Such a solar-powered WSS can harvest hydrogen day and night, demonstrating a potential for application in sustainable renewable energy.     

In Situ Separation of Chemical Reaction Systems Based on a Special Wettable PTFE Membrane

Oil–water separation is a worldwide subject because of the increasing demands in numerous applications, involving separation of immiscible products from chemical reaction systems in synthetic industry. Owing to the limitations of low efficiency, high energy consumption, and multiple operations in conventional methods, membranes with special wettability have been widely developed in recent years to effectively separate various oil–water systems. However, few works on treating chemical reaction systems have been reported because of the lack of stability of current membranes in harsh environments, especially during long‐term work. Herein, a continuous in situ separation of chemical reaction systems based on a special wettable porous polytetrafluoroethylene membrane is successfully conducted. The membrane possesses (1) an intrinsic (with no modification) special wettability of highly hydrophobic/oleophilic in air and superoleophilic under water and 2) an excellent long‐term durability in acidic, alkaline, saline, organic, or heating environments. The in situ separation process exhibits both large separation flux (>3500 L m^?2 h^?1) and high product purity (>99.00%) by continuously filtering synthetic products without interrupting chemical reactions, which is of great significance in industrial fields.     

I3–/I– Redox Enhanced Sodium Metal Batteries by Using Graphene Oxide Encapsulated Mesoporous Carbon Sphere Cathode

Sodium-metal batteries (SMBs) employing transition-metal-free cathodes are of great importance for energy storage applications that require low cost and high energy density. A strategy to enhance the energy density of transition-metal-free-cathode SMBs by transforming the electrolyte from a dead mass to an energy-storage contributor is reported. NaI is used for the partial substitution of NaClO₄ in the electrolyte and thus provides the additional electrochemistry of I₃⁻/I⁻ redox couple to enhance battery performance. Graphene oxide (GO) encapsulated mesoporous (10 nm) carbon spheres (N-MCS@GO) that are nitrogen-doped (15.71 at%) are fabricated as the cathode for the I₃⁻/I⁻ redox enhanced SMBs. It is experimentally demonstrated that: the mesoporous structure increases the capacitive energy storage by providing a substantial interface that enhances the electrochemistry of I₃⁻/I⁻ redox couples; and encapsulation of the mesoporous carbon spheres with GO suppresses self-discharge and increases Coulombic efficiencies from 70.4% to 91.9%. In full-cell configuration, N-MCS@GO working with the NaI-activated electrolyte can deliver a capacity of 279.6 mAh g⁻¹ with an energy density of 459.2 Wh kg⁻¹ in 0.5–3 V at 200 mA g⁻¹. I₃⁻/I⁻ redox in the full cell maintains its activity without obvious decay after 1000 cycles at 1 A g⁻¹, highlighting the practical application of the I₃⁻/I⁻ redox enhanced SMBs.     

Interface states in polyfluorene-based metal–insulator–semiconductor devices

Hybrid metal–insulator–semiconductor structures based on ethyl-hexyl substituted polyfluorene (PF2/6) as the active polymer semiconductor were fabricated on a highly doped p-Si substrate with Al₂O₃ as the insulating oxide layer. We present detailed frequency-dependent capacitance–voltage (C–V) and conductance–voltage characteristics of the semiconductor/insulator interface. PF2/6 undergoes a transition to an ordered crystalline phase upon thermal cycling from its nematic-liquid crystalline phase, confirmed by our atomic force microscope images. Thermal cycling of the PF2/6 films significantly improves the quality of the (PF2/6)/Al₂O₃ interface, which is identified as a reduced hysteresis in the C–V curve and a decreased interface state density (D_it) from ∼3.9 × 10¹² eV⁻¹ cm⁻² to ∼3.3 × 10¹¹ eV⁻¹ cm⁻² at the flat-band voltage. Interface states give rise to energy levels that are confined to the polymer/insulator interface. A conductance loss peak, observed due to the capture and emission of carriers by the interface states, fits very well with a single time constant model from which the D_it values are inferred.