Nonaqueous rechargeable lithium–oxygen batteries (LOBs) are one of the most promising candidates for future electric vehicles and wearable/flexible electronics. However, their development is severely hindered by the sluggish kinetics of the ORR and OER during the discharge and charge processes. Here, we employ MOF-assisted spatial confinement and ionic substitution strategies to synthesize Ru single atoms riveted with nitrogen-doped porous carbon (Ru SAs-NC) as the electrocatalytic material. By using the optimized Ru0.3 SAs-NC as electrocatalyst in the oxygen-breathing electrodes, the developed LOB can deliver the lowest overpotential of only 0.55 V at 0.02 mA cm–2. Moreover, in-situ DEMS results quantify that the e–/O2 ratio of LOBs in a full cycle is only 2.14, indicating a superior electrocatalytic performance in LOB applications. Theoretical calculations reveal that the Ru–N4 serves as the driving force center, and the amount of this configuration can significantly affect the internal affinity of intermediate species. The rate-limiting step of the ORR on the catalyst surface is the occurrence of 2e– reactions to generate Li2O2, while that of the OER pathway is the oxidation of Li2O2. This work broadens the field of vision for the design of single-site high-efficiency catalysts with maximum atomic utilization efficiency for LOBs.

Conductive polymer hydrogels are receiving considerable attention in applications such as soft robots and human-machine interfaces. Herein, a transparent and highly ionically conductive hydrogel that integrates sensing, UV-filtering, water-retaining, and anti-freezing performances is achieved by the organic combination of tannic acid-coated hydroxyapatite nanowires (TA@HAP NWs), polyvinyl alcohol (PVA) chains, ethylene glycol (EG), and metal ions. The highly ionic conductivity of the hydrogel enables tensile strain, pressure, and temperature sensing capabilities. In particular, in terms of the hydrogel strain sensors based on ionic conduction, it has high sensitivity (GF = 2.84) within a wide strain range (350%), high linearity (R 2 = 0.99003), fast response (≈50 ms) and excellent cycle stability. In addition, the incorporated TA@HAP NWs act as a nano-reinforced filler to improve the mechanical properties and confer a UV-shielding ability upon the hydrogel due to its size effect and the characteristics of absorbing ultraviolet light waves, which can reflect and absorb short ultraviolet rays and transmit visible light. Meanwhile, owing to the water-locking effect between EG and water molecules, the hydrogel exhibits freezing resistance at low temperatures and moisture retention at high temperatures. This biocompatible and multifunctional conductive hydrogel provides new ideas for the design of novel ionic skin devices.

Multiplexed detection of extracellular vesicle (EV)-derived microRNAs (miRNAs) plays a critical role in facilitating disease diagnosis and prognosis evaluation. Herein, we developed a highly specific nucleic acid detection platform for simultaneous quantification of several EV-derived miRNAs in constant temperature by integrating the advantages of a clustered regularly interspaced short palindromic repeats/CRISPR associated nucleases (CRISPR/Cas) system and rolling circular amplification (RCA) techniques. Particularly, the proposed approach demonstrated single-base resolution attributed to the dual-specific recognition from both padlock probe-mediated ligation and protospacer adjacent motif (PAM)-triggered cleavage. The high consistency between the proposed approach RCA-assisted CRISPR/Cas9 cleavage (RACE) and reverse transcription quantitative polymerase chain reaction (RT-qPCR) in detecting EV-derived miRNAs’ abundance from both cultured cancer cells and clinical lung cancer patients validated its robustness, revealing its potentials in the screening, diagnosis, and prognosis of various diseases. In summary, RACE is a powerful tool for multiplexed, specific detection of nucleic acids in point-of-care diagnostics and field-deployable analysis.

The rational design of excellent electrocatalysts is significant for triggering the slow kinetics of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in rechargeable metal–air batteries. Hereby, we report a bifunctional catalytic material with core–shell structure constructed by Co3O4 nanowire arrays as cores and ultrathin NiFe-layered double hydroxides (NiFe LDHs) as shells (Co3O4@NiFe LDHs). The introduction of Co3O4 nanowires could provide abundant active sites for NiFe LDH nanosheets. Most importantly, the deposition of NiFe LDHs on the surface of Co3O4 can modulate the surface chemical valences of Co, Ni, and Fe species via changing the electron donor and/or electron absorption effects, finally achieving the balance and optimization of ORR and OER properties. By this core–shell design, the maximum ORR current densities of Co3O4@NiFe LDHs increase to 3–7 mA cm–2, almost an order of magnitude increases compared to pure NiFe LDH (0.45 mA cm–2). Significantly, an OER overpotential as low as 226 mV (35 mA cm–2) is achieved in the designed core–shell catalyst, which is comparable to and/or even better than those of commercial Ir/C. Hence, the primary zinc–air battery employing Co3O4@NiFe LDH as an air electrode achieves a high specific capacity (667.5 mA h g–1) and first-class energy density (797.6 W h kg–1); the rechargeable battery can show superior reversibility, excellent stability, and voltage gaps of ∼0.8 V (∼60% of round-trip efficiency) in >1200 continuous cycles. Furthermore, the flexible quasi-solid-state zinc–air battery with bendable ability holds practical potential in portable and wearable electronic devices.

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Recently, near‐infrared light (NIR) photocatalysts, such as up‐converting materials, Bi2WO6, Cu2(OH)PO4, and carbon quantum dots, have been found and are attracting attention for environmental cleaning and energy conversion, because NIR light constitutes nearly half of the energy output. However, the photocatalytic efficiency is low for these new types of NIR photocatalysts, which has limited their widespread application owing to their insufficient NIR‐light absorption. In this work, we use gold (Au) nanorods to enhance the NIR‐light absorption of Bi2WO6, a typical visible and novel NIR‐light photocatalyst, thus the enhancement of its NIR‐light photocatalytic and photoelectrochemical properties are achieved. This can be attributed to the surface plasmon resonance (SPR) effects and wide‐range NIR light harvesting of the Au nanorods. The present work provides key guidelines for the improvement of NIR‐light photocatalysts and could also help design and prepare novel photocatalysts.

This article seeks to derive insight on battery charging control using electrochemistry models. Directly using full order complex multi-partial differential equation (PDE) electrochemical battery models is difficult and sometimes impossible to implement. This article develops an approach for obtaining optimal charge control schemes, while ensuring safety through constraint satisfaction. An optimal charge control problem is mathematically formulated via a coupled reduced order electrochemical-thermal model which conserves key electrochemical and thermal state information. The Legendre-Gauss-Radau (LGR) pseudo-spectral method with adaptive multi-mesh-interval collocation is employed to solve the resulting nonlinear multi-state optimal control problem. Minimum time charge protocols are analyzed in detail subject to solid and electrolyte phase concentration constraints, as well as temperature constraints. The optimization scheme is examined using different input current bounds, and an insight on battery design for fast charging is provided. Experimental results are provided to compare the tradeoffs between an electrochemical-thermal model based optimal charge protocol, an electro-thermal-aging model based balanced charge protocol, and a traditional charge protocol.

A 4.5 V “dual carbon” LIC device is constructed based on all nitrogen doped graphene nanostructures. It could achieve an ultrahigh energy density of 187.9 W h kg−1 at a high power density of 2250 W kg−1 due to the alleviating kinetic mismatch.