Solvated Electrons Generated on the Surface of Na-SPHI for Boosting Visible Light Photocatalytic Hydrogen Evolution with Ultra-High AQE.

Enhancing the utilization of visible-light-active semiconductors with an excellent apparent quantum efficiency (AQE) remains a significant and challenging goal in the realm of photocatalytic water splitting. In this study, a fully condensed sulfur-doped poly(heptazine imide) metalized with Na (Na-SPHI) is synthesized by an ionothermal method by using eutectic NaCl/LiCl mixture as the ionic solvent. Comprehensive characterizations of the obtained Na-SPHI reveal several advantageous features, including heightened light absorption, facilitated exciton dissociation, and expedited charge transfer. More importantly, solvated electron, powerful reducing agents, can be generated on the surface of Na-SPHI upon irradiation with visible light. Benefiting from above advantage, the Na-SPHI exhibits an excellent H2 evolution rate of 571.8 µmol·h-1 under visible light illumination and a super-high AQE of 61.7% at 420 nm. This research emphasizes the significance of the solvated electron on the surface of photocatalyst in overcoming the challenges associated with visible light-driven photocatalysis, showcasing its potential application in photocatalytic water splitting.

Tunable Surface Charge of Layered Double Hydroxide Membranes Enabling Osmotic Energy Harvesting from Anion Transport.

Membrane-based osmotic energy harvesting is a promising technology with zero carbon footprint. High-performance ion-selective membranes (ISMs) are the core components in such applications. Recent advancement in 2D nanomaterials opens new avenues for building highly efficient ISMs. However, the majority of the explored 2D nanomaterials have a negative surface charge, which selectively enhances cation transport, resulting in the underutilization of half of the available ions. In this study, ISMs based on layered double hydroxide (LDH) with tunable positive surface charge are studied. The membranes preferentially facilitate anion transport with high selectivity. Osmotic energy harvesting device based on these membranes reached a power density of 2.31 W m-2 under simulated river/sea water, about eight times versus that of a commercial membrane tested under the same conditions, and up to 7.05 W m-2 under elevated temperature and simulated brine/sea water, and long-term stability with consistent performance over a 40-day period. A prototype reverse electrodialysis energy harvesting device, comprising a pair of LDH membranes and commercial cation-selective membranes, is able to simultaneously harvest energy from both cations and anions achieving a power density of 6.38 W m-2 in simulated river/sea water, demonstrating its potential as building blocks for future energy harvesting systems.

Boron nitride-alginate coordination interactions enabling hydrogels with enhanced mechanical strength and heat resistance.

Developing large-scale hydrogels with high tensile strength and robust mechanical properties is an intricate challenge of great industrial significance. In this study, we demonstrate an efficient method for producing nanocomposite hydrogels with extraordinary mechanical properties. Our approach involves a two-step process: an initial stage of pre-cross-linking boron nitride (BN)-enriched pre-gel sodium alginate, followed by cross-linking with metal ions. In stark contrast to conventional sodium alginate hydrogels (SA), our newly formulated 'BS hydrogel' exhibited an impressive tensile strength exceeding 41 MPa and improved thermal resistance. Moreover, the reconstituted BS hydrogel exhibited tensile strengths ranging from 47 to 96 MPa and elastic moduli ranging from 199 to 1184 MPa, depending on the cross-linking metal ions. These findings indicate the multifaceted potential of the BS hydrogel, which is poised to revolutionize many applications and represents a significant step forward in hydrogel technology for industrial applications.

Interfacial Modification of Lithium Metal Anode by Boron Nitride Nanosheets.

Metallic lithium (Li) is the most attractive anode for Li batteries because it holds the highest theoretical specific capacity (3860 mA h g-1) and the lowest redox potential (-3.040 V vs SHE). However, the poor interface stability of the Li anode, which is caused by the high reactivity and dendrite formation of metallic Li upon cycling, leads to undesired electrochemical performance and safety issues. While two-dimensional boron nitride (BN) nanosheets have been utilized as an interfacial layer, the mechanism on how they stabilize the Li-electrolyte interface remains elusive. Here, we show how BN nanosheet interlayers suppress Li dendrite formation, enhance Li ion transport kinetics, facilitate Li deposition, and reduce electrolyte decomposition. We show through both simulation and experimental data that the desolvation process of a solvated Li ion within the interlayer nanochannels kinetically favors Li deposition. This process enables long cycling stability, reduced voltage polarization, improved interface stability, and negligible volume expansion. Their application as an interfacial layer in symmetric cells and full cells that display significantly improved electrochemical properties is also demonstrated. The knowledge gained in this study provides both critical insights and practical guidelines for designing a Li metal anode with significantly improved performance.

Enhancing Electrochemical Performance of Aluminum-Oxygen Batteries with Graphene Aerogel Cathode.

Aluminum-oxygen batteries (AOBs) own the benefits of high energy density (8.14 kWh kg-1 ), low cost, and high safety. However, the design of a cathode with high surface area, structure integrity, and good catalytic performance is still challenging for rechargeable AOBs. Herein, the fabrication of a robust self-supporting cathode using 3D graphene aerogel (3DGA) for rechargeable AOBs is demonstrated. Electroanalysis showed that the 3DGA presented good catalytic activity in both oxygen reduction and evolution reactions, which allowed the AOB to operate for >90 cycles with low overpotentials at a current density of 0.2 mA cm-2 , and a high Coulombic efficiency of ca. 99% using ionic liquid as electrolyte. In comparison, the cell with the carbon paper cathode can only cycle for 50 rounds. The excellent cyclic performance can be attributed to the porous structure, large surface area, good electric conductivity, and catalytic activity of the 3DGA, which is prospective to be applied for other metal-air batteries, fuel cells, and supercapacitors.

Longitudinal trajectory of amplitude of low-frequency fluctuation changes in breast cancer patients during neoadjuvant chemotherapy-A preliminary prospective study.

There is growing evidence that the amplitude of low-frequency fluctuation (ALFF) changes in breast cancer patients after chemotherapy. However, longitudinal changes in ALFF during chemotherapy are unclear. To assess the trajectory of ALFF changes during chemotherapy, 36 breast cancer patients underwent both resting-state functional magnetic resonance imaging and neuropsychological testing at three time points, including before neoadjuvant chemotherapy (NAC) (time point 0, TP0), after one cycle of NAC (before the second cycle of NAC, TP1), and upon completion of NAC (pre-operation, TP2). Healthy controls (HC) received the same assessments at matching time points. We compared the longitudinal changes of ALFF in the NAC and two HC groups. In the NAC group, compared with TP0, ALFF values in the right orbital part of the inferior frontal gyrus, left medial orbital part of the superior frontal gyrus, right insula, left medial part of the superior frontal gyrus, and right middle frontal gyrus declined significantly at TP1 and TP2. Compared with TP1, there were no significant changes in ALFF values at TP2. In the two HC groups, there were no significant changes in ALFF at corresponding intervals. We concluded that for breast cancer patients receiving NAC, ALFF values declined significantly in some brain regions after one cycle of NAC and then remained stable until the completion of NAC, and most of the brain regions with ALFF changes were located in the frontal lobe.

Large-scale production of MXenes as nanoknives for antibacterial application.

Antimicrobial resistance of existing antibacterial agents has become a pressing issue for human health and demands effective antimicrobials beyond conventional antibacterial mechanisms. Two-dimensional (2D) nanomaterials have attracted considerable interest for this purpose. However, obtaining a high yield of 2D nanomaterials with a designed morphology for effective antibacterial activity remains exceptionally challenging. In this study, an efficient one-step mechanical exfoliation (ECO-ME) method has been developed for rapidly preparing Ti3C2 MXenes with a concentration of up to 30 mg mL-1. This synthetic pathway involving mechanical force endows E-Ti3C2 MXene prepared by the ECO-ME method with numerous irregular sharp edges, resulting in a unique nanoknife effect that can successfully disrupt the bacterial cell wall, demonstrating better antibacterial activity than the MXenes prepared by conventional wet chemical etching methods. Overall, this study provides a simple and effective method for preparing MXenes on a large scale, and its antibacterial effects demonstrate great potential for E-Ti3C2 in environmental and biomedical applications.

Lubricin (PRG-4) anti-fouling coating for surface-enhanced Raman spectroscopy biosensing: towards a hierarchical separation system for analysis of biofluids.

Surface-enhanced Raman Spectroscopy (SERS) is a powerful optical sensing technique that amplifies the signal generated by Raman scattering by many orders of magnitude. Although the extreme sensitivity of SERS enables an extremely low limit of detection, even down to single molecule levels, it is also a primary limitation of the technique due to its tendency to equally amplify 'noise' generated by non-specifically adsorbed molecules at (or near) SERS-active interfaces. Eliminating interference noise is thus critically important to SERS biosensing and typically involves onerous extraction/purification/washing procedures and/or heavy dilution of biofluid samples. Consequently, direct analysis within biofluid samples or in vivo environments is practically impossible. In this study, an anti-fouling coating of recombinant human Lubricin (LUB) was self-assembled onto AuNP-modified glass slides via a simple drop-casting method. A series of Raman spectra were collected using rhodamine 6G (R6G) as a model analyte, which was spiked into NaCl solution or unprocessed whole blood. Likewise, we demonstrate the same sensing system for the quantitative detection of L-cysteine spiked in undiluted milk. It was demonstrated for the first time that LUB coating can mitigate the deleterious effect of fouling in a SERS sensor without compromising the detection of a target analyte, even in a highly fouling, complex medium like whole blood or milk. This feat is achieved through a molecular sieving property of LUB that separates small analytes from large fouling species directly at the sensing interface resulting in SERS spectra with low background (i.e., noise) levels and excellent analyte spectral fidelity. These findings indicate the great potential for using LUB coatings together with an analyte-selective layer to form a hierarchical separation system for SERS sensing of relevant analytes directly in complex biological media, aquaculture, food matrix or environmental samples.

Tuning nanofiltration membrane performance: OH-MoS2 nanosheet engineering and divalent cation influence on fouling and organic removal.

Natural organic matter (NOM) present in surface water causes severe organic fouling of nanofiltration (NF) membranes employed for the production of potable water. Calcium (Ca2+) and magnesium (Mg2+) are alkaline earth metals present in natural surface water and severely exacerbate organic fouling owing to their ability to cause charge neutralization, complexation, and bridging of NOM and the membrane surface. Hence, it is of practical significance to engineer membranes with properties suitable for addressing organic fouling in the presence of these cations. This study employed OH-functionalized molybdenum disulphide (OH-MoS2) nanosheets as nanofillers via the interfacial polymerization reaction to engineer NF membranes for enhanced removal of NOM and fouling mitigation performance. At an optimized concentration of 0.010 wt.% of OH-MoS2 nanosheet, the membrane was endowed with higher hydrophilicity, negative charge and rougher membrane morphology which enhanced the pure water permeance by 46.33% from 11.2 to 16.39 L m-2 h-1 bar-1 while bridging the trade-off between permeance and salt selectivity. The fouling performance was evaluated using humic acid (HA) and sodium alginate (SA), which represent the hydrophobic and hydrophilic components of NOM in the presence of 0, 0.5, and 1 mM Ca2+ and Mg2+, respectively, and the performance was benchmarked with control and commercial membranes. The modified membrane exhibited normalized fluxes of 95.09% and 93.26% for HA and SA, respectively, at the end of the 6 h filtration experiments, compared to the control membrane at 89.71% and 74.25%, respectively. This study also revealed that Ca2+ has a more detrimental effect than Mg2+ on organic fouling and NOM removal. The engineered membrane outperformed the commercial and the pristine membranes during fouling tests in the presence of 1 mM Ca2+ and Mg2+ in the feed solution. In summary, this study has shown that incorporating OH-MoS2 nanosheets into membranes is a promising strategy for producing potable water from alternative water sources with high salt and NOM contents.

A Thermochromic, Viscoelastic Nacre-like Nanocomposite for the Smart Thermal Management of Planar Electronics.

Cutting-edge heat spreaders for soft and planar electronics require not only high thermal conductivity and a certain degree of flexibility but also remarkable self-adhesion without thermal interface materials, elasticity, arbitrary elongation along with soft devices, and smart properties involving thermal self-healing, thermochromism and so on. Nacre-like composites with excellent in-plane heat dissipation are ideal as heat spreaders for thin and planar electronics. However, the intrinsically poor viscoelasticity, i.e., adhesion and elasticity, prevents them from simultaneous self-adhesion and arbitrary elongation along with current flexible devices as well as incurring high interfacial thermal impedance. In this paper, we propose a soft thermochromic composite (STC) membrane with a layered structure, considerable stretchability, high in-plane thermal conductivity (~ 30 W m-1 K-1), low thermal contact resistance (~ 12 mm2 K W-1, 4-5 times lower than that of silver paste), strong yet sustainable adhesion forces (~ 4607 J m-2, 2220 J m-2 greater than that of epoxy paste) and self-healing efficiency. As a self-adhesive heat spreader, it implements efficient cooling of various soft electronics with a temperature drop of 20 °C than the polyimide case. In addition to its self-healing function, the chameleon-like behavior of STC facilitates temperature monitoring by the naked eye, hence enabling smart thermal management.

Relationship between the Co-Continuous Morphology of Immiscible Polymer Blends and the Structure of an In Situ Formed Graft Copolymer.

In order to get stable co-continuous morphology in immiscible polymer blends, besides reducing the interfacial tension, the compatibilizer should not only promote the formation of flat interface between different phases, but also not hinder the coalescence of the dispersed phase. Herein, the relationship between the morphology of the compatibilized polystyrene/nylon 6/styrene-maleic anhydride (PS/PA6/SMA) immiscible polymer blends and the structures of the in-situ formed SMA-g-PA6 graft copolymers as well as the processing conditions are studied. Two kinds of SMA are used: SMA28 (28 wt.% MAH) and SMA11 (11 wt.% MAH). After melt blending with PA6, the in-situ formed copolymer SMA28-g-PA6 has on average of four PA6 side chains, while that of SMA11-g-PA6 has only one. Dissipative particle dynamics simulation results indicate that both SMA28-g-PA6 copolymer and PS/PA6/SMA28 blends tend to form co-continuous structure, while those related to SMA11 intend to form sea-island morphologies. These results are correct only at relatively low rotor speed (60 rpm). When the rotor speed is higher (105 rpm), sea-island morphologies are obtained in SMA28 systems, while that for SMA11 ones are co-continuous. This indicates that higher shear stress can elongate the minor phase domains to form flat interfaces, while the SMA28-g-PA6 copolymers can be pulled out from the interface.

Optimizing the band structure of sponge-like S-doped poly(heptazine imide) with quantum confinement effect towards boosting visible-light photocatalytic H2 generation.

Simultaneously manipulating the nanostructure and band structure of semiconductors for boosting the photocatalytic performance of photocatalyts is highly desirable. Herein, a series of hierarchical sponge-like S-doped poly(heptazine imide) (HS-SPHI) assembled by ultrathin nanosheets were successfully fabricated via a facile bottom-up supramolecular preassembly approach using melamine (MA) and trithiocyanuric acid (TTCA) as precursors. Benefiting from the synergistic effect of the S-doping and their unique hierarchical porous structure coupled with quantum confinement effect, the as-obtained HS-SPHIs are endowed with extended visible-light response, improved charge separation efficiency, enlarged specific surface area, and enhanced thermodynamic driving force for water reduction. As a result, all the HS-SPHIs exhibit remarkable boosting visible-light (>420 nm) photocatalytic H2evolution (PHE). The maximum PHE rate achieved by HS-SPHI-650 can be up to 3584.2 µmol g-1h-1, with an apparent quantum efficiency (AQE) of 14.67 % at 420 nm, which is about 22.4 times than that of pristine bulk g-C3N4 (B-GCN). We believe that this work will provide a significant strategy for optimizing the band structure of PCN in order to improve its photocatalytic performance.

Functionalized MoO3 Nanosheets for High-Efficiency RhB Removal.

2D nanostructured materials have been applied for water purification in the past decades due to their excellent separation and adsorption performance. However, the functional 2D nanostructured molybdenum trioxide (MoO3)has rarely been reported for the removal of dyes. Here, functionalized MoO3 (F-MoO3) nanosheets are successfully fabricated with a high specific surface area (106 cc g-1) by a one-step mechanochemical exfoliation method as a highly effective adsorbent for removing dyes from water. According to the Raman, X-ray photoelectron spectroscopy, Fourier transform infrared (FTIR), and selected area electron diffraction analysis, functional groups (hdroxyl groups, amide groups, amine groups and amino groups) are identified in the as-prepared F-MoO3 nanosheets. The attached functional groups not only facilitate the dispersal ability of F-MoO3 nanosheets but also enhance the adsorption capacities. Thus, the performance (up to 556 mg g-1 when the initial concentration of Rhodamine B solution is 100 mg L-1) of as-prepared F-MoO3 nanosheets is almost two times higher than other reported MoO3 materials. Furthermore, the FTIR spectra, isotherm, and several factors (e.g., adsorbent dosage and adsorbate dosage) are also systematically investigated to explore the adsorption mechanism. Therefore, this work demonstrates that the F-MoO3 nanosheets are a promising candidate for wastewater treatment.

Removal of natural organic matter from surface water sources by nanofiltration and surface engineering membranes for fouling mitigation - A review.

Given that surface water is the primary supply of drinking water worldwide, the presence of natural organic matter (NOM) in surface water presents difficulties for water treatment facilities. During the disinfection phase of the drinking water treatment process, NOM aids in the creation of toxic disinfection by-products (DBPs). This problem can be effectively solved using the nanofiltration (NF) membrane method, however NOM can significantly foul NF membranes, degrading separation performance and membrane integrity, necessitating the development of fouling-resistant membranes. This review offers a thorough analysis of the removal of NOM by NF along with insights into the operation, mechanisms, fouling, and its controlling variables. In light of engineering materials with distinctive features, the potential of surface-engineered NF membranes is here critically assessed for the impact on the membrane surface, separation, and antifouling qualities. Case studies on surface-engineered NF membranes are critically evaluated, and properties-to-performance connections are established, as well as challenges, trends, and predictions for the field's future. The effect of alteration on surface properties, interactions with solutes and foulants, and applications in water treatment are all examined in detail. Engineered NF membranes containing zwitterionic polymers have the greatest potential to improve membrane permeance, selectivity, stability, and antifouling performance. To support commercial applications, however, difficulties related to material production, modification techniques, and long-term stability must be solved promptly. Fouling resistant NF membrane development would be critical not only for the water treatment industry, but also for a wide range of developing applications in gas and liquid separations.

Charged Boron Nitride Nanosheet Membranes for Improved Organic Solvent Nanofiltration.

Two-dimensional nanomaterial-based membranes have earned broad attention because of their excellent capability of separation performance in a mixture that can challenge the conventional membrane materials utilized in the organic solvent nanofiltration (OSN) field. Boron nitride (BN) nanosheet membranes have displayed superb stability and separation ability in aqueous and organic solutions compared to the widely researched analogous graphene-based membranes; nevertheless, the concentration polarization of organic dye pollutants fades their separation performance and eclipses their potential adoption as a feasible technology. Herein, PDDA-modified BN (PBN) and sodium alginate-modified BN (SBN) nanosheet membranes with a thinner laminar structure are facially fabricated to improve the molecule separation performance compared to that of the pristine BN membrane. In aqueous separation application, the SBN membranes (2 µm) can reject positively charged dyes up to 100% and the PBN membrane (2 µm) could reject negatively charged dyes up to 100%. Impressively, the PBN membranes (3 µm) and SBN membranes (3 µm) demonstrate record high performances in OSN, with a permeance of 809 L m-2 h-1 bar-1 and 97.71% rejection to acid fuchsin in acetonitrile and 290 L m-2 h-1 bar-1 and 94.94% rejection to Azure B in dimethyl sulfoxide, respectively. The charged PBN and SBN nanosheet membranes demonstrate stable separation capability, exhibiting their potential for practical water and organic solvent purification processes.

Improved Photo-Excited Carriers Transportation of WS2 -O-Doped-Graphene Heterostructures for Solar Steam Generation.

Two-dimensional (2D) transition metal dichalcogenides and graphene have revealed promising applications in optoelectronic and energy storage and conversion. However, there are rare reports of modifying the light-to-heat transformation via preparing their heterostructures for solar steam generation. In this work, commercial WS2 and sucrose are utilized as precursors to produce 2D WS2 -O-doped-graphene heterostructures (WS2 -O-graphene) for solar water evaporation. The WS2 -O-graphene evaporators demonstrate excellent average water evaporation rate (2.11 kg m-2  h-1 ) and energy efficiency (82.2%), which are 1.3- and 1.2-fold higher than WS2 and O-doped graphene-based evaporators, respectively. Furthermore, for the real seawater with different pH values (pH 1 and 12) and rhodamine B pollutants, the WS2 -O-graphene evaporators show great average evaporation rates (≈2.08 and 2.09 kg m-2  h-1 , respectively) for producing freshwater with an extremely low-grade of dye residual and nearly neutral pH values. More interestingly, due to the self-storage water ability of WS2 -O-graphene evaporators, water evaporation can be implemented without the presence of bulk water. As a result, the evaporation rate reaches 3.23 kg m-2  h-1 , which is ≈1.5 times higher than the regular solar water evaporation system. This work provides a new approach for preparing 2D transition metal dichalcogenides and graphene heterostructures for efficient solar water evaporation.

Changes in Degree Centrality and Functional Connectivity after the First Cycle of Neoadjuvant Chemotherapy in Newly Diagnosed Breast Cancer: A Longitudinal Study.

Purpose: To evaluate the longitudinal changes of brain degree centrality (DC) and functional connectivity (FC) in breast cancer patients after the first cycle of neoadjuvant chemotherapy (NAC). Methods: Thirty-five breast cancer patients were included in the NAC group. Resting-state functional magnetic resonance imaging (rs-fMRI) and neuropsychological test were performed at baseline before NAC (time point 0, TP0) and after the first cycle of NAC (time point 1, TP1). The healthy controls (HC) included 30 healthy subjects and received the same rs-fMRI scan and neuropsychological test as the above-mentioned NAC group at one time point. DC and FC analyses were conducted to assess brain connectivity of all participants. Receiver operating characteristic (ROC) curve was used to assess the ability of DC and FC in distinguishing patients before and after chemotherapy. Results: In the NAC group, the Self-Rating Anxiety Scale scores decreased significantly over time. At TP0 and TP1, the Digital Span Test forward score of the NAC group was significantly lower than that of the HC group. In the NAC group, DC in the right middle frontal gyrus and left precentral gyrus/middle frontal gyrus decreased significantly at TP1, and FC between the left precentral gyrus/middle frontal gyrus and bilateral precuneus was significantly reduced at TP1. Through ROC analysis, we found that the area under the curve (AUC) of DC, FC, and the combined model in distinguishing patients in TP0 or TP1 was 0.7886, 0.7665, and 0.8278, respectively. Conclusions: Brain connectivity, involving executive and motor function related brain areas, changes in the short term after NAC treatment in breast cancer patients.

Enhancing Thermal Conductivity of Polyvinylidene Fluoride Composites by Carbon Fiber: Length Effect of the Filler.

Thermally conductive polyvinylidene fluoride (PVDF) composites were prepared by incorporating carbon fibers (CFs) with different lengths (286.6 ± 7.1 and 150.0 ± 2.3 µm) via cold pressing, followed by sintering. The length effects of the CF on the thermal conductivity, polymer crystallization behaviors, and mechanical properties of the PVDF composites were studied. The through-plane thermal conductivity of the PVDF composites increased significantly with the rise in CF loadings. The highest thermal conductivity of 2.89 W/(m∙K) was achieved for the PVDF composites containing 40 wt.% shorter CFs, ~17 times higher than that of the pure PVDF (~0.17 W/(m∙K)). The shorter CFs had more pronounced thermal conductive enhancement effects than the original longer CFs at higher filler loadings. CFs increased the storage modulus and the glass transition temperature of the PVDF. This work provides a new way to develop thermally conductive, mechanically, and chemically stable polymer composites by introducing CFs with different lengths.

Two-Dimensional Membranes with Highly Charged Nanochannels for Osmotic Energy Conversion.

Inadequate mass transportation of semipermeable membranes causes poor osmotic energy conversion from salinity-gradient. Here, the lamellar graphene oxide membranes (GOMs) constructed with numerous fusiform-like nanochannels, that are pre-filled with negatively charged polyanion electrolytes, to both enhance the ion permeability and ion selectivity of the membrane for energy harvest from the salinty gradient, were developed. The as-prepared membrane achieved the maximum output power density of ∼4.94 W m-2 under a 50 fold salinity gradient, which is 3.5 fold higher than that of pristine GOM. The enhancement could be ascribed to the synergistic impact of the expanded nanochannels and the enhanced space charge density. Via feeding with the artificial salinity water and monovalent cation electrolytes, the system could realise the power output up to 14.7 W m-2 and 34.1 W m-2 , respectively. Overall, this material design strategy could provide an alternative concept to effectively enhance ion transport of other two-dimensional (2D) membranes for specific purposes.

Boosting Osmotic Energy Conversion of Graphene Oxide Membranes via Self-Exfoliation Behavior in Nano-Confinement Spaces.

Introducing alien intercalations to sub-nanometer scale nanochannels is one desirable strategy to optimize the ion transportation of two-dimensional nanomaterial membranes for improving osmotic energy harvest (OEH). Diverse intercalating agents have been previously utilized to realize this goal in OEH, but with modest performance, complex operations, and physicochemical uncertainty gain. Here, we employ the self-exfoliation behavior of oxidative fragments (OFs) from graphene oxide basal plane under an alkaline environment to encapsulate detached OFs in nanochannels for breaking a trade-off between permeability and selectivity, boosting power density from 1.8 to 4.9 W m-2 with a cation selectivity of 0.9 and revealing a negligible decline in power density and trade-off during a long-term operation test (∼168 h). The strategy of membrane design, employing the intrinsically self-exfoliated OFs to decorate the nanochannels, provides an alternative and facile approach for ion separation, OEH, and other nano-fluidic applications.