Planar Zn-Ion Microcapacitors with High-Capacity Activated Carbon Anode and VO2 (B) Cathode.

The downsizing of microscale energy storage devices plays a crucial role in powering modern emerging devices. Therefore, the scientific focus on developing high-performance microdevices, balancing energy density and power density, becomes essential. In this context, we explore an advanced Microplotter technique to fabricate hybrid planar Zn-ion microcapacitors (ZIMCs) that exhibit dual charge storage characteristics, with an electrical double layer capacitor type activated carbon anode and a battery type VO2 (B) cathode, aiming to achieve energy density surpassing supercapacitors and power density exceeding batteries. Effective loading of VO2 (B) cathode electrode materials combined with activated carbon anode onto confined planar microelectrodes not only provides reversible Zn2+ storage performance but also mitigates dendrite formation. This not only results in superior charge storage performance, including areal energies of 2.34 µWh/cm2 (at 74.76 µW/cm2) and 0.94 µWh/cm2 (at 753.12 µW/cm2), exceeding performance of zinc nanoparticle anode and activated carbon cathode based ZIMCs, but also ensures stable capacity retention of 87% even after 1000 cycles and free from any unwanted dendrites. Consequently, this approach is directed toward the development of high-performance ZIMCs by exploring high-capacity materials for efficient utilization on microelectrodes and achieving maximum possible capacities within the constraints of the limited device footprint.

Porous nickel-cobalt phosphate with oxygen-rich vacancies in situ grown on dopamine-modified cellulose textiles as self-supporting high mass loadings supercapacitor electrode.

Transition-metal phosphates/phosphides showcase significant promise for energy-related applications because of their high theoretical electrochemical characteristics. However, sluggish electro/ion transfer rates and kinetically unfavorable reaction sites hinder their application at high mass loading. Herein, a self-supporting electrode based on transition-metal phosphates was successfully fabricated via a one-step electrodeposition process. The nanosheet structure of transition-metal phosphates, formed by interconnecting nanoparticles, effectively mitigates the impact of stress and achieves a high mass-loading (21 mg cm-2) of the electrode. Additionally, the oxygen vacancy-rich and porous nanostructure of transition-metal phosphates endows the as-prepared electrodes with a significantly increased conductivity and fast ion migration rate for enhancing electrochemical kinetics. Consequently, the as-fabricated transition-metal phosphate electrode displays the highest areal specific capacity of 39.2F cm-2. Furthermore, the asymmetric supercapacitor achieves a maximum energy density of 0.79 mWh cm-2 and a high capacity retention of 93.0 % for 10000 cycles under 60 mA cm-2. This work provides an ideal strategy for fabricating flexible electrodes with high mass loading and synthesizing transition-metal phosphate electrodes rich in oxygen vacancies.

Recent Advances in Engineering Fe-N-C Catalysts for Oxygen Electrocatalysis in Zn-Air Batteries.

Fe-N-C single-atom catalysts (SACs) have emerged as one of the most promising candidates for oxygen electrocatalysis due to their maximized atom utilization efficiency, high intrinsic activity, and strong metal-support interaction. Significant progress has been made in engineering Fe-N-C SACs for oxygen electrocatalysis in Zn-air batteries (ZABs). This review provides a comprehensive overview of the recent advancements in Fe-N-C SACs, with a special focus on effective engineering strategies, their performance in oxygen electrocatalysis, and their potential applications in ZABs. The review also discusses the key challenges and future directions in the development of Fe-N-C SACs for efficient and durable oxygen electrocatalysis in ZABs. This review aims to offer valuable insights into the current state of research in this field and to guide future efforts in the development of advanced oxygen electrocatalysts for ZABs.

Vertical VOPO4·2H2O Nanosheets with Richly Exposed (200) Plane Enable Fast-Kinetics High-Mass-Loading Cathodes for Zn-Ion Batteries.

Extending the layer spacing of the (001) planes to regulate the mobility of Zn2+ is widely adopted to optimize the performance of VOPO4·2H2O cathode for zinc-ion batteries. However, the unique function originating from other planes is often neglected. Herein, an effective in situ conversion methodology is proposed for the synthesis of the (200) oriented growth of vertical VOPO4·2H2O nanosheets with oxygen vacancies (VOd-VOPO4). Theoretical simulation and ex situ characterizations collaboratively demonstrate that the richly exposed (200) plane with tetragonal channels can offer quick pathways for in-layer and cross-layer migration of Zn2+, exhibiting enhanced transfer kinetics with improved reversible capacity. Meanwhile, efficient electron migration in VOd-VOPO4 is guaranteed by the introduction of oxygen vacancies. Thus, the as-prepared VOd-VOPO4 harvests exceptional discharge capacity, impressive rate capability, and remarkable long-cycle stability at high mass loading. Notably, the VOd-VOPO4 electrode (15 mg cm-2) provides a capacity of 213.5 mAh g-1 with an ultrahigh areal capacity of 3.02 mAh cm-2 at 0.1 A g-1, showing great potential for applications. This study highlights the orientated growth strategy for facilitating ion storage and migration, offering novel perspectives on the development of high-performance electrodes and beyond.

Occurrence, removal, and fate of benzothiazoles (BTHs) and benzotriazoles (BTRs) in two wastewater treatment plants in New York State, USA.

Benzothiazoles (BTHs) and benzotriazoles (BTRs) are widely used in various consumer products. However, their occurrence and fate in wastewater treatment plants (WWTPs) in the United States remain poorly understood. In this study, wastewater and sludge samples were collected from two WWTPs from the Albany area of New York State (WWTPA and WWTPB) and the concentrations of three BTH derivatives (BTH, 2-OH-BTH, and 2-Me-S-BTH) and five BTR derivatives (1-OH-BTR, XTR, 4-OH-BTR, TTR, and BTR) were determined. The geometric mean (GM) concentrations of Σ(BTHs) and Σ(BTRs) in influent were in the range of 7550-8690 and 4590-6240 ng/L, whereas those in effluent were 6650-7150 and 4620-6800 ng/L, respectively. In the influent of two WWTPs, BTH, BTR, and TTR were identified as the major chemicals at respective GM concentrations of 8440, 4200, and 1280 ng/L in WWTPA, and 7300, 1180, and 2090 ng/L in WWTPB. The removal efficiencies of BTHs and BTRs following activated sludge treatment were < 80 %, and Σ(BTRs) showed a negative removal in both WWTPs. The respective mass loadings of Σ(BTHs) and Σ(BTRs) were 7240 and 5200 mg/d/1000 individuals in WWTPA, and 3530 and 2140 mg/d/1000 individuals in WWTPB. The environmental emissions of Σ(BTHs) and Σ(BTRs) from WWTP discharges were estimated at 3110-6030 and 2160-5700 mg/d/1000 individuals, respectively. Overall, BTHs and BTRs are not efficiently removed in WWTP processes. This study provides baseline information regarding the loading, fate, and discharge of BTHs and BTRs from WWTPs in the USA.

Optimizing Li Plating Behavior via Controlling Areal Capacity of a Cathode for Cycling Stability on 600 W h kg-1 Lithium-Metal Batteries.

To meet the requirements of long-range electric vehicles and aviation, the high-mass-loading electrode with high areal capacity is a promising solution to realize ultrahigh-energy lithium-metal batteries (LMBs). However, enabling the operation of high mass loading with a long cycling life is still a challenge without in-depth investigation. Herein, we figured out that the polarization appearing in the cycled lithium-metal anodes (LMAs) is responsible for the poor cycling of LMBs with high mass loading. Moreover, the origin of fast degradation of LMAs is affected by mass loading through the Li plating process, which is decided by the Li plating morphology. Hence, manipulating the mass loading can directly promote lithium reversibility and further mitigate cell polarization in LMBs, endowing high-mass-loading LMBs with excellent cycling stability. Consequently, we achieved an ultrahigh energy density (605 W h kg-1) of a 10.1 A h pouch cell with an excellent retention of 91.7% capacity and 86% energy after 50 cycles. The feasible strategy points out a promising approach for designing high-energy-density LMBs in the future.

Chlorination Design for Highly Stable Electrolyte toward High Mass Loading and Long Cycle Life Sodium-Based Dual-Ion Battery.

Sodium-based dual ion batteries (SDIBs) have garnered significant attention as novel energy storage devices offering the advantages of high-voltage and low-cost. Nonetheless, conventional electrolytes exhibit low resistance to oxidation and poor compatibility with electrode materials, resulting in rapid battery failure. In this study, for the first time, a chlorination design of electrolytes for SDIB, is proposed. Using ethyl methyl carbonate (EMC) as a representative, chlorine (Cl)-substituted EMC not only demonstrates increased oxidative stability ascribed to the electron-withdrawing characteristics of chlorine atom, electrolyte compatibility with both the cathode and anode is also greatly improved by forming Cl-containing interface layers. Consequently, a discharge capacity of 104.6 mAh g-1 within a voltage range of 3.0-5.0 V is achieved for Na||graphite SDIB that employs a high graphite cathode mass loading of 5.0 mg cm-2, along with almost no capacity decay after 900 cycles. Notably, the Na||graphite SDIB can be revived for an additional 900 cycles through the replacement of a fresh Na anode. As the mass loading of graphite cathode increased to 10 mg cm-2, Na||graphite SDIB is still capable of sustaining over 700 times with ≈100% capacity retention. These results mark the best outcome among reported SDIBs. This study corroborates the effectiveness of chlorination design in developing high-voltage electrolytes and attaining enduring cycle stability of Na-based energy storage devices.

Ti─O─C Bonding at 2D Heterointerfaces of 3D Composites for Fast Sodium Ion Storage at High Mass Loading Level.

3D composite electrodes have shown extraordinary promise as high mass loading electrode materials for sodium ion batteries (SIBs). However, they usually show poor rate performance due to the sluggish Na+ kinetics at the heterointerfaces of the composites. Here, a 3D MXene-reduced holey graphene oxide (MXene-RHGO) composite electrode with Ti─O─C bonding at 2D heterointerfaces of MXene and RHGO is developed. Density functional theory (DFT) calculations reveal the built-in electric fields (BIEFs) are enhanced by the formation of bridged interfacial Ti─O─C bonding, that lead to not only faster diffusion of Na+ at the heterointerfaces but also faster adsorption and migration of Na+ on the MXene surfaces. As a result, the 3D composite electrodes show impressive properties for fast Na+ storage. Under high current density of 10 mA cm-2, the 3D MXene-RHGO composite electrodes with high mass loading of 10 mg cm-2 achieve a strikingly high and stable areal capacity of 3 mAh cm-2, which is same as commercial LIBs and greatly exceeds that of most reported SIBs electrode materials. The work shows that rationally designed bonding at the heterointerfaces represents an effective strategy for promoting high mass loading 3D composites electrode materials forward toward practical SIBs applications.

In Situ Fabrication of Hierarchical CuO@CoNi-LDH Composite Structures for High-Performance Supercapacitors.

Layered double hydroxide (LDH) materials, despite their high theoretical capacity, exhibit significant performance degradation with increasing load due to their low conductivity. Simultaneously achieving both high capacity and high rate performance is challenging. Herein, we fabricated vertically aligned CuO nanowires in situ on the copper foam (CF) substrate by alkali-etching combined with the annealing process. Using this as a skeleton, electrochemical deposition technology was used to grow the amorphous α-phase CoNi-LDH nanosheets on its surface. Thanks to the high specific surface area of the CuO skeleton, ultrahigh loading (̃16.36 mg cm-2) was obtained in the fabricated CF/CuO@CoNi-LDH electrode with the cactus-like hierarchical structure, which enhanced the charge transfer and ion diffusion dynamics. The CF/CuO@CoNi-LDH electrode achieved a good combination of high areal capacitance (33.5 F cm-2) and high rate performance (61% capacitance retention as the current density increases 50 times). The assembled asymmetric supercapacitor device demonstrated a maximum potential window of 0-1.6 V and an energy density of 1.7 mWh cm-2 at a power density of 4 mW cm-2. This work provides a feasible strategy for the design and fabrication of high-mass-loading LDH composites for electrochemical energy storage applications.

Activating Ion Channels in Collapsed Hydrogel Derived Densified MXene Films with Cellulose Nanofibers to Overcome the Areal Versus Volumetric Capacitance Trade-Off.

Concomitant achievement of all three performance pillars of a supercapacitor device, namely gravimetric, areal, and volumetric capacitance is a grand challenge. Nevertheless, its fulfilment is indispensable for commercial usage. Although, high compactness is the fundamental requirement to achieve high volumetric performance, it severely affects ion transportation in thick electrodes. Such trade-off makes it extremely challenging to realize very high areal and volumetric performance simultaneously. Here, a collapsed hydrogel strategy is introduced to develop MXene/cellulose nanofiber (CNF) based densified electrodes that offer excellent ion transportation despite a massive increase in areal mass loading (>70 mg cm-2). Quasi-oriented MXene/CNF (MXCF) hydrogels are produced through an electric field-guided co-assembly technique. Ambient dehydration of these hydrogels incorporates numerous pores in the resultant compact electrodes due to crumpling of the MXene sheets, while CNF ensures connectivity among the locally blocked pores in different length scales. The resultant collapsed MXCF densified electrode shows a remarkably high areal capacitance of 16 F cm-2 while simultaneously displaying a high volumetric capacitance of 849.8 F cm-3 at an ultrahigh mass loading of up to 73.4 mg cm-2. The universality of strategy, including the co-assembly of hydrogel and its collapse, is further demonstrated to develop high-performance asymmetric and wearable devices.

Endogenous Interfacial Mo-C/N-Mo-S Bonding Regulates the Active Mo Sites for Maximized Li+ Storage Areal Capacity.

Active sites, mass loading, and Li-ion diffusion coefficient are the benchmarks for boosting the areal capacity and storage capability of electrode materials for lithium-ion batteries. However, simultaneously modulating these criteria to achieve high areal capacity in LIBs remains challenging. Herein, MoS2 is considered as a suitable electroactive host material for reversible Li-ion storage and establish an endogenous multi-heterojunction strategy with interfacial Mo-C/N-Mo-S coordination bonding that enables the concurrent regulation of these benchmarks. This strategy involves architecting 3D integrated conductive nanostructured frameworks composed of Mo2C-MoN@MoS2 on carbon cloth (denoted as C/MMMS) and refining the sluggish kinetics in the MoS2-based anodes. Benefiting from the rich hetero-interface active sites, optimized Li adsorption energy, and low diffusion barrier, C/MMMS reaches a mass loading of 12.11 mg cm-2 and showcases high areal capacity and remarkable rate capability of 9.6 mAh cm-2@0.4 mA cm-2 and 2.7 mAh cm-2@6.0 mA cm-2, respectively, alongside excellent stability after 500 electrochemical cycles. Moreover, this work not only affirms the outstanding performance of the optimized C/MMMS as an anode material for supercapacitors, underscoring its bifunctionality but also offers valuable insight into developing endogenous transition metal compound electrodes with high mass loading for the next-generation high areal capacity energy storage devices.

The LiV3O8 Superlattice Cathode with Optimized Zinc Ion Insertion Chemistry for High Mass-Loading Aqueous Zinc-Ion Batteries.

Resolving the sluggish transport kinetics of divalent Zn2+ in the cathode lattice and improving mass-loading performance are crucial for advancing the zinc-ion batteries (AZIBs) application. Herein, PEO-LiV3O8 superlattice nanosheets (PEO-LVO) with expanded interlayer spacing (1.16 nm) are fabricated to provide a high-rate, stable lifetime, and large mass-loading cathode. The steady in-plane expansion without shrinkage after the first cycle, but reversible H+/Zn2+ co-insertion in PEO-LVO are demonstrated by operando synchrotron X-ray diffraction and ex situ characterizations. Moreover, the large capacity of PEO-LVO is traced back to the optimized Zn2+ insertion chemistry with increased Zn2+ storage ratio, which is facilitated by the interlayer PEO in lowering the Zn2+ diffusion barrier and increased number of active sites from additional interfaces, as anticipated by density functional theory. Due to the optimized ion insertion resulting in stalled interfacial byproducts and rapid kinetics, PEO-LVO achieves excellent high mass-loading performance (areal capacity up to 6.18 mAh cm-2 for freestanding electrode with 24 mg cm-2 mass-loading and 2.8 mAh cm-2 at 130 mA cm-2 for conventional electrode with 27 mg cm-2 mass-loading). As a proof-of-concept, the flexible all-solid-state fiber-shaped AZIBs with high mass-loading woven into a fabric can power an electronic watch, highlighting the application potential of PEO-LVO cathode.

Occurrence and fate of N-nitrosamines in full-scale domestic wastewater treatment plants and their impact on receiving waters along the Lijiang River, China.

Domestic wastewaters contaminated with N-nitrosamines pose a significant threat to river ecosystems worldwide, particularly in urban areas with riparian cities. Despite widespread concern, the precise impact of these contaminants on receiving river waters remains uncertain. This study investigated eight N-nitrosamines in wastewater treatment plants (WWTPs) and their adjacent receiving river, the Lijiang River in Guilin City, Southwest China. By analyzing thirty wastewater samples from five full-scale WWTPs and twenty-three river water samples from Guilin, we quantified the mass loads of N-nitrosamines discharged into the surrounding watershed via domestic effluents. The results revealed that N-nitrosodimethylamine (10-60 ng/L), N-nitrosodiethylamine (3.4-22 ng/L), and N-nitrosopyrrolidine (not detected-4.5 ng/g) were predominant in influents, effluents, and sludge, respectively, with the overall removal efficiencies ranging from 17.7 to 65.6% during wastewater treatment. Cyclic activated sludge system and ultraviolet disinfection were effective in removing N-nitrosamines (rates of 59.6% and 24.3%), while chlorine dioxide disinfection promoted their formation. A total of 30.4 g/day of N-nitrosamine mass loads were observed in the Lijiang River water, with domestic effluents contributing about 31.3% (19.4 g/day), followed by livestock breeding wastewater (34.5%, 12.0 g/day), and unknown sources (24.7%, 7.5 g/day). These findings highlight the critical role of WWTPs in transporting N-nitrosamines to watersheds and emphasize the urgent need for further investigation into other potential sources of N-nitrosamine pollution within watersheds.

Fabrication of Soft-Hard Heterostructure Porous Carbon with Enhanced Performance for High Mass-Loading Aqueous Supercapacitors.

With the increasing attention to energy and environmental issues, the high value-added utilization of biomass and pitch to functional carbon materials has become an important topic in science and technology. In this work, the soft-hard heterostructure porous carbon (NRP-HPC) is prepared by bio-template method, in which biomass and pitch are used as hard carbon and soft carbon precursors, respectively. The prepared NRP-HPC-4 shows high specific surface area (2293 m2 g-1), suitable pore size distribution, good conductivity (0.25 Ω cm-1), and strong wettability. The synergistic effect of soft carbon and hard carbon ensures the composite material exhibiting excellent electrochemical performance for high mass loading (12.0 mg cm-2) aqueous supercapacitor, i.e., high specific capacitance (304.69 F g-1 at 0.1 A g-1), high area capacitance (3.67 F cm-2 at 0.1 A g-1), high volumetric specific capacitance (202.74 F cm-3 at 0.1 A g-1), low open-circuit voltage attenuation rate (21.04 mV h-1), good voltage retention (79.12%), and excellent cyclic stability (92.04% capacitance retention and 100% coulombic efficiency after 20 000 cycles). The composite technology of soft carbon and hard carbon not only ensures the prepared porous carbon electrode materials with enhanced electrochemical performance, but also realizes the high value-added coupling utilization of biomass and pitch.

Integrated hierarchical porous lignin-based carbon electrode for boosting membrane-free capacitive deionization areal adsorption capacity.

The development of high value-added lignin-based functional porous carbon electrodes with excellent properties from sustainable industry lignin powder remains a challenge. This work aims to create robust, binder-free, conductive additives-free, and current collector-free monolithic porous carbon electrodes using industrial lignin powder for membrane-free capacitive deionization (CDI). The material exhibits high mechanical strength, hierarchical porosity structure, large uniform size, and thickness of just a few millimetres (<2.6 mm). In a three-electrode supercapacitor system, the areal specific capacitance of CLCA300-3-1.0 reaches 5.03-1.02 F cm-2 when the scan rate between 1 and 20 mV s-1 in 1 M NaCl solution. As CDI electrodes, the charge efficiency of CLCA300-3-1.0 at different voltages of 1.2 V, 1.4 V and 1.6 V is 0.53, 0.72 and 0.71, respectively. The energy consumption of CLCA280-3-1.0, CLCA300-3-1.0 and CLCA320-3-1.0 tested at 1.2 V are 3.27, 3.40 and 3.25 Wh m-3, respectively. In addition, with thickness increasing to 1.5 mm, the developed CLCA300-3-1.5 electrode exhibits an areal adsorption capacity of 0.46 mg cm-2, and relative highly capacity retention of 84.78 % after 70 cycles. The impressive desalination performance is attributed to the well-designed hierarchical porosity, superhydrophilicity and robust monolithic structure.

Nitrogen-Doped Cellulose-Derived Porous Carbon Fibers for High Mass-Loading Aqueous Supercapacitors.

Biomass-based porous carbon with renewability and flexible structure tunability is a promising electrode material for supercapacitors. However, there is a huge gap between experimental research and practical applications. How to maintain good electrochemical performance of high mass-loading electrodes and suppress the self-discharge of supercapacitors is a key issue that urgently needs to be addressed. The structure regulation of electrode materials such as heteroatom doping is a promising optimization strategy for high mass-loading electrodes. In this work, nitrogen-doped cellulose-derived porous carbon fibers (N-CHPCs) were prepared by a facile bio-template method using cotton cellulose as raw material and urea as dopant. The prepared N-CHPCs have high specific surface area, excellent hierarchical porous structure, partial graphitization properties and suitable heteroatom content. The assembled high mass-loading (12.8 mg cm-2; 245 µm) aqueous supercapacitor has excellent electrochemical performance, i. e., low open-circuit voltage attenuation rate (21.39 mV h-1), high voltage retention rate (78.81 %), high specific capacitance (295.8 F g-1 at 0.1 A g-1), excellent area capacitance (3.79 F cm-2 at 0.1 A g-1), excellent cycling stability (97.28 % over 20,000 cycles at 1.0 A g-1). The excellent performance of high mass-loading N-CHPCs is of great significance for their practical applications in advanced aqueous supercapacitors.

Occurrence, source apportionment, and ecological risk of legacy and emerging per- and poly-fluoroalkyl substances (PFASs) in the Dahei river basin of a typical arid region in China.

Per- and poly-fluoroalkyl substances (PFASs) are artificial chemicals with broad commercial and industrial applications. Many studies about PFASs have been conducted in densely industrial and populated regions. However, fewer studies have focused on the PFASs' status in a typical arid region. Here, we investigated 30 legacy and emerging PFASs in surface water from the mainstream and tributaries of the Dahei River. Our results revealed that total PFASs concentrations (∑30PFASs) in water ranged from 3.13 to 289.1 ng/L (mean: 25.40 ng/L). Perfluorooctanoic acid (PFOA) had the highest mean concentration of 2.44 ng/L with a 100% detection frequency (DF), followed by perfluorohexanoic acid (PFHxA) (mean concentration: 1.34 ng/L, DF: 59.26%). Also, perfluorohexane sulfonate (DF: 44.44%), perfluorobutane sulfonate (DF: 88.89%), and perfluorooctane sulfonate (PFOS) (DF: 92.59%) had mean concentrations of 12.94, 2.00, and 1.05 ng/L, respectively. Source apportionment through ratio analysis and principal component analysis-multiple linear regression analysis showed that treated or untreated sewage, aqueous film-forming foam, degradation of precursors, and fluoropolymer production were the primary sources. The PFOS alternatives were more prevalent than those of PFOA. Conductivity, total phosphorus, and chlorophyll a positively correlated with Σ30PFASs and total perfluoroalkane sulfonates concentrations. Furthermore, ecological risk assessment showed that more attention should be paid to perfluorooctadecanoic acid, perfluorohexadecanoic acid, perfluorooctane sulfonate, perfluorohexane sulfonate, and (6:2 and 6:2/8:2) polyfluoroalkyl phosphate mono- and di-esters. The mass load of PFASs to the Yellow River was 1.28 kg/year due to the low annual runoff in the Dahei River in the arid region. This study provides baseline data for PFASs in the Dahei River that can aid in the development of effective management strategies for controlling PFASs pollution in typical arid regions in China.

A Ternary (P, Se, S) Covalent Inorganic Framework as a Shuttle Effect-Free Cathode for Li-S Batteries.

Developing new cathode materials to avoid shuttle effect of Li-S batteries at source is crucial for practical high-energy applications, which, however, remains a great challenge. Herein, a new class of sulfur-containing ternary covalent inorganic framework (CIF), P4 Se6 S40 , is explored, by simply comelting powders of P, S, and Se. The P4 Se6 S40 CIF with open framework enables all active sites available during electrochemical reactions, giving a high capacity delivery. Moreover, introducing Se atoms can improve intrinsic electronic conductivity of S chains yet without remarkably compromising the capacity because Se is also electrochemical active to lithium storage. More importantly, Se atoms in S-Se chains can serve as a heteroatom barrier to block the bonding of S atoms around, effectively avoiding the formation of long-chain polysulfides during cycling. Besides, stable Li3 PS4 with a tetrahedral configuration formed after lithiation works as not only a good ionic conductor to promote Li ion diffusion, but a three-dimensional spatial barrier and chemical anchor to suppress the dissolution and diffusion of lithium polysulfides (LiPS), further inhibiting the shuttle effect. Consequently, the P4 Se6 S40 cathode delivers high capacity and excellent capacity retention with even a high loading of 10.5 mg cm-2 which far surpasses the requirement for commercial applications.

Zn-induced formation of polymetallic carbonate hydroxide cathodes with high mass loading for high performance aqueous alkaline Zn-based batteries.

Developing high mass loading cathodes with high capacity and durable life cycles is greatly worthwhile and challenging for alkaline aqueous rechargeable Zn-based batteries (AAZBs). Herein, we demonstrate an efficient zinc-induced strategy to rationally develop Zn-Ni-Co carbonate hydroxides/hydroxides heterostructure nanosheet array with an extremely high mass loading of 9.2 mg cm-2 on Ni foam (ZNC/NF) as such a superior cathode for AAZBs. It is discovered that Ni-Co hydroxide nanowires can be transformed into Zn-Ni-Co carbonate hydroxides/hydroxides heterostructure nanosheet with rich defect structures after the introduction of Zn during the synthetic process. The formed heterostructures and rich defect structures can enhance ion and electron transfer efficiency, thus ensuring the excellent electrochemical performance under high loading condition. Consequently, the ZNC/NF//Zn battery shows an outstanding areal capacity of 2.1 mAh cm-2 at 5 mA cm-2, with an ultrahigh energy density of 3.6 mWh cm-2. Moreover, the battery can still retain a high capacity of 0.42 mAh cm-2 after 5000 cycles at 50 mA cm-2, suggesting strong long-term cycling stability. This research enables pave the way for the rational design and manufacture of advanced electrode materials with large mass loadings.

Occurrence, mass loading, and post-control temporal trend of legacy perfluoroalkyl substances (PFASs) in the middle and lower Yangtze River.

Present study focused on per- and polyfluoroalkyl substances (PFASs) occurrence in dry and wet seasons in the middle and lower Yangtze River (YZR) and changing temporal trends after years of control. Results revealed that perfluorooctanoic acid (PFOA) was 75 % of total PFAS concentrations (∑11PFASs). ∑11PFASs were ranged 0.20-28.49 ng/L and 1.17-112.84 µg/kg in water and sediment. The logKoc of perfluoroalkyl carboxylic acids was positive with the carbon chain length (p < 0.05, r2 = 0.78). A meta-analysis of results from 16 peer-reviewed publications about PFASs in the YZR showed that fluorochemical industries strongly influenced the high PFAS levels in the detected scenes. PFOA was still the primary pollutant. Individual PFAS in the lower reach was higher than those in the middle reach. The mass loading of PFASs imported into the sea was 10.80 t/y. This study will help develop effective approaches for controlling emerging pollutants in the YZR.