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The exploration of solid-state lithium metal batteries (SLMBs) with high-performance hybrid polymer electrolytes is in demand for the development of novel energy-storage systems with enhanced safety and high theoretical energy densities. In this study, for the first time, we report the synthesis of P(dodecafluoroheptyl methacrylate-co-methyl methacrylate) (P(DFMA-co-MMA)) as a polymer matrix to provide adsorption sites for Li+. Moreover, succinonitrile was introduced to suppress polymer crystallization, and the long fluorocarbon chains connected in series provided long-range channels for Li+ transmission. The resultant long-chain-fluorocarbon-driven hybrid solid polymer electrolyte (LFSPE) membranes could afford an exceptional ion conductivity of 6.78 × 10−4 S cm−1 at 25 °C, with a wide electrochemical stable window (0–4.713 V vs. Li/Li+) and high lithium-ion transference number (0.47). The poly(diallyl dimethyl ammonium)-bis(trifluoromethanesulfonyl)imide (PDDA-TFSI) interlayer was exploited to inhibit the side reactions on the Li metal surface and promote homogeneous Li plating. Thus, steady Li plating/stripping in LFSPE could be achieved under an areal capacity of 0.2 mA h cm−2 for 2000 h. The LiFePO4 (LFP), LiCoO2 (LCO) and LiNi0.8Co0.1Mn0.1O2 (NCM811) cells using the modified SLMB design scheme exhibited excellent rate capacity (specific capacity of 138.8, 109.6 and 145.8 mA h g−1 at 1C, respectively) and long-term cycling stability (98.8% capacity retention after 500 cycles for LFP; 81.4% and 71.9% capacity retention after 300 cycles for LCO and NCM811, respectively). This work offers a novel and effective SLMB system with high safety based on a hybrid solid polymer electrolyte. [ABSTRACT FROM AUTHOR]

Developing efficient catalysts for the oxygen evolution reaction (OER) is critical to supplying renewable and clean energy. In heterogeneous catalysis, a strategy with a second active site has been developed to improve OER catalytic performance. Here we propose the design of dual-active sites consisting of two adjacent TMN4(OH) (TM = Cr/Mn/Fe/Co/Ni/Cu) sites confined to a nanotube and use first-principles calculations to investigate their OER mechanisms. It was found that the OER pathway including the chemical step of O2 generation from direct O–O coupling (*O + *O → 2* + O2, ΔG5) can be carried out on the TMN4(OH) dual-active sites. It associates with a newly linear OER activity trend function, with ΔG5 as the descriptor. Importantly, the potential-independent process should occur under mild conditions, which limits ΔG5 to be relatively negative. This law of thermodynamic feasibility gives an optimal overpotential (0.18 V) for the FeN4(OH) dual-active sites. Besides, the ΔG5 descriptor is only related to the binding energy of *O, implying a facile route to achieve optimal activity. Our proposed dual-active-sites catalysis provides new insights into the fundamental understanding of OER mechanisms and theoretical guidelines for the accelerated discovery of efficient OER catalysts. [ABSTRACT FROM AUTHOR]

The enzyme–inorganic hybrid nanoflowers have attracted wide attention due to their high surface area, enhanced enzymatic activity, and excellent stability for enzyme immobilization. However, difficulties of separation limit their application in the field of food processing. In this work, novel magnetic lipase–Cu3(PO4)2 nanoflowers (lipase@MNFs) were successfully synthesized by the coprecipitation method. The lipase@MNFs are composed of a flower-like copper phosphate skeleton and magnetic ferroferric oxide core with lipase as the coupling agent. The magnetic nanoflowers can be separated quickly from the reaction system under an external magnetic field. Compared with free lipase (∼84.00 U g−1), the lipase@MNFs exhibited higher enzymatic activity (92.63 U g−1, at 37 °C and pH 7.4) and better thermal and pH stability (at 60 °C and pH 10.0). In addition, the magnetic nanoflowers have been applied in the solvent-free biosynthesis of benzyl acetate through benzyl alcohol and vinyl acetate. These results suggest that the design of magnetic nanoflowers opens up a new way to improve the catalytic activity and stability of lipase, and simplify the enzyme separation. The magnetic nanoflowers have potential applications in various enzymatic industrial processes. [ABSTRACT FROM AUTHOR]

A crucial obstacle to photoelectrochemical (PEC) water splitting is the scarcity of p-type photocathodes with superior charge separation ability. Nanocrystals with well-defined anisotropic shapes offer an exciting opportunity for tailoring the PEC performance of semiconductors. In this paper, various SnS nanostructures with different dimensions were controllably synthesized using a colloidal injection method. Through controlling the roles of 1-dodecanethiol (DDT) and thioacetamide for nanocrystal nucleation and growth, different morphologies of SnS nanostructures were fabricated. 0-D SnS nanoparticles (NPs) were fabricated by the hot-injection method, while temperature-controlled cool-injection facilitated the formation of 1-D SnS nanorods (NRs) and 2-D SnS nanosheets (NSs). Due to the efficient charge transfer and separation, photocathodes fabricated from 1-D nanorods exhibited much superior activity than 0-D nanoparticles and 2-D nanosheets. Our research demonstrates the enormous potential of dimensional tailoring of anisotropic SnS nanostructures for PEC activity. [ABSTRACT FROM AUTHOR]

More efforts are being made in hybridizing TiO2 photocatalysts with graphene-analogue g-C3N4. However, a fundamental understanding of the interfacial behavior of charge carriers is still lacking. In this paper, the impact of exposed facets and structural defects on the charge transfer mechanism around heterostructured interfaces was investigated. Due to the electron-rich feature and the relatively lower CB position, integrating g-C3N4 with 101-TiO2 facilitated the Z-scheme recombination of electrons in the CB of 101-TiO2 and holes in the VB of g-C3N4. Creating oxygen vacancies in TiO2 resulted in the 4- and 24-fold increased photoactivity than blank TiO2 and g-C3N4. 001-Facets of TiO2 however were prone to accept electrons from the CB of g-C3N4, forming the conventional Type II junction with poor photoreduction ability. For 001-TiO2/g-C3N4 heterojunctions, nitrogen vacancies in g-C3N4 played a more important role in separating the charge carriers. Our discovery provides an efficient way to design high-performance TiO2-based heterostructured photocatalysts through facet and defect engineering. [ABSTRACT FROM AUTHOR]