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A new sulfonated diamine monomer, 4,4′-((1,4-phenylenebis(methylene))bis(azanediyl))dibenzenesulfonic acid (PMABSA) was synthesized and used as the sole aqueous reactant to fabricate a novel reverse osmosis (RO) membrane with trimesoyl chloride (TMC), in place of conventional m -phenylene diamine (MPD). The separation performance of the PMABSA/TMC membrane was optimized by the response surface method (RSM) by means of evaluating the pure water permeability (PWP) and salt rejection (R) to NaCl, and optimal results of PWP of 1.18 ± 0.03 L m −2 h −1 bar −1 , and R of 98.2 ± 0.4%, respectively, were achieved at 1.55 MPa. Owing to the rigid benzene ring in the center of the molecule, which may have a blocking effect during the interfacial polymerization (IP) process, the resulting barrier layer was less compact and had low thickness. Both molecular dynamics (MD) simulation and positron annihilation spectroscopy (PAS) revealed the creation of sufficient free volumes in the sulfonated polyamide matrix. Regardless of the slightly lower water permeation, the PMABSA/TMC membrane exhibited a superior rejection ability to all the ions compared to that of commercial SW30HR (Dow Chemical) in a model seawater separating test. Overall, all the results indicated the great potential of the novel membrane as a new choice of non-MPD RO membrane for seawater desalination. [ABSTRACT FROM AUTHOR]

Highlights: Ultra-thin asymmetric composite solid-state electrolytes with ultralight areal density were designed for solid-state lithium metal batteries, achieving interfacial stability to Li metal and high-voltage cathode. The improved mechanical properties of the electrolyte contribute to the inhibition of Li dendrite growth was demonstrated by both experimental and theoretical simulations. The assembled pouch cell exhibited a high gravimetric/volume energy density of 344.0 Wh kg−1/773.1 Wh L−1. Solid-state lithium metal batteries (SSLMBs) show great promise in terms of high-energy–density and high-safety performance. However, there is an urgent need to address the compatibility of electrolytes with high-voltage cathodes/Li anodes, and to minimize the electrolyte thickness to achieve high-energy–density of SSLMBs. Herein, we develop an ultrathin (12.6 µm) asymmetric composite solid-state electrolyte with ultralight areal density (1.69 mg cm−2) for SSLMBs. The electrolyte combining a garnet (LLZO) layer and a metal organic framework (MOF) layer, which are fabricated on both sides of the polyethylene (PE) separator separately by tape casting. The PE separator endows the electrolyte with flexibility and excellent mechanical properties. The LLZO layer on the cathode side ensures high chemical stability at high voltage. The MOF layer on the anode side achieves a stable electric field and uniform Li flux, thus promoting uniform Li+ deposition. Thanks to the well-designed structure, the Li symmetric battery exhibits an ultralong cycle life (5000 h), and high-voltage SSLMBs achieve stable cycle performance. The assembled pouch cells provided a gravimetric/volume energy density of 344.0 Wh kg−1/773.1 Wh L−1. This simple operation allows for large-scale preparation, and the design concept of ultrathin asymmetric structure also reveals the future development direction of SSLMBs. [ABSTRACT FROM AUTHOR]

Mobility-on-demand (MoD) systems have recently emerged as a promising paradigm of one-way vehicle sharing for sustainable personal urban mobility in densely populated cities. We assume the capability of a MoD system to be enhanced by deploying robotic shared vehicles that can autonomously cruise the streets to be hailed by users. A key challenge of the MoD system is that of real-time, fine-grained mobility demand and traffic flow sensing and prediction. This paper presents novel Gaussian process (GP) decentralized data fusion and active sensing algorithms for real-time, fine-grained traffic modeling and prediction with a fleet of MoD vehicles. The predictive performance of our decentralized data fusion algorithms are theoretically guaranteed to be equivalent to that of sophisticated centralized sparse GP approximations. We derive consensus filtering variants requiring only local communication between neighboring vehicles. We theoretically guarantee the performance of our decentralized active sensing algorithms. When they are used to gather informative data for mobility demand prediction, they can achieve a dual effect of fleet rebalancing to service mobility demands. Empirical evaluation on real-world datasets shows that our algorithms are significantly more time-efficient and scalable in the size of data and fleet while achieving predictive performance comparable to that of state-of-the-art algorithms. [ABSTRACT FROM PUBLISHER]

Transition metal sulfides are favorable candidates for anode materials in sodium-ion batteries (SIBs), but they are difficult to fully utilize owing to the agglomeration caused by high interfacial energy at the nanoscale during the process of nanoization or compounding with carbon materials. Herein, we make full use of the advantages of the porous structure of electrode membrane (EM) to obtain a new composite electrode material with nickel monosulfide (NiS) nanoparticles uniformly spread in the membrane pores through covalent bonds. The developed 3D hierarchical porous structure and high specific area of membrane matrix provide strong space for the exposure of NiS active sites, and the NiS nanolayers loaded in the membrane pores also exhibit high porosity, thereby greatly improving its utilization. Compared with pure NiS electrode, it exhibits excellent sodium storage performance during long-term cycles and delivers an inspiring reversible capacitance of 658.3 mA h g−1 at 50 mA g−1. Moreover, the designed composite electrode exhibits excellent flexibility and structural stability before and after long cycles. The favorable performance is the result of the synergy between the 3D hierarchical porous structure and the high utilization of NiS. Considering that the unique porous structure of membrane technology can provide a positive effect on the improvement of NiS utilization, this research provides a simple and feasible design idea for SIBs composite electrodes with high utilization of nano-active materials by porous structural materials. [Display omitted] • Flexible composite anodes are prepared with NiS spread in the 3D hierarchical pores of electrode membrane by C-S bonds. • NiS exhibits high utilization for Na+ storage owing to the exposure of active sites by the membrane porous structure. • The maximum reversible capacity in SIBs is 658.3 mA h g−1 at 50 mA g−1. • This paper provides an idea for SIBs composite anodes with high utilization of nano-active materials by porous structure. [ABSTRACT FROM AUTHOR]