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The precise monitoring of H2S has aroused immense research interest in the biological and biomedical fields since it is exposed as a third endogenous gasotransmitter. Hence, there is an urgent requisite to explore an ultrasensitive and economical H2S detection system. Herein, we report a simple strategy to configure an extremely sensitive electrochemical sensor with a 2D nanosheet-shaped layered double hydroxide (LDH) wrapped carbon nanotubes (CNTs) nanohybrid (CNTs@LDH), where a series of CNTs@CuMn-LDH nanohybrids with varied amounts of LDH nanosheets grafted on a conductive CNTs backbone has been synthesized via a facile coprecipitation approach. Taking advantage of the unique core–shell structure, the integrated electrochemically active CuMn-LDH nanosheets on the conductive CNTs scaffold, the maximum interfacial collaboration, and the superior specific surface area with a plethora of surface active sites and ultrathin LDH layers, the as-prepared CNTs@CuMn-LDH nanoarchitectures have exhibited superb electrocatalytic activity toward H2S oxidation. Under the optimum conditions, the electrochemical sensor based on the CNTs@CuMn-LDH nanohybrid shows remarkable sensing performances for H2S determination in terms of a wide linear range and a low detection limit of 0.3 nM (S/N = 3), high selectivity, reproducibility, and durability. With marvelous efficiency achieved, the proposed sensing platform has been practically used in in situ detection of abiotic H2S efflux produced by sulfate reducing bacteria and real-time in vitro tracking of H2S concentrations from live cells after being excreted by a stimulator which in turn might serve as early diseases diagnosis. Thus, our core–shell hybrid nanoarchitectures fabricated via structural integration strategy will open new horizons in material synthesis, biosensing systems, and clinical chemistry.

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temperature range. Simultaneously, the average thermoelectric figure of merit (ZT) is even enhanced a little in spite of the increased corresponding thermal conductivity. We further calculated the engineering power factor (PF)eng, output power, engineering figure of merit (ZT)eng and leg efficiency by taking into account of the Thomson effect. Assuming Tc = 300 K and Th = 548 K, leg length ~2 mm, an output power of ~1.77 W cm-2 and leg efficiency η of ~10.1% are finally obtained for the optimized composition MgAg0.97Sb0.995.

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The preparation of ordered metal organic frameworks (MOFs) will be a critical process for MOF-based nanoelectrodes in the future. In this work, we develop a novel approach to fabricating a type of MOF electrode based on flexible amino-functionalized graphene paper modified with 2D oriented assembly of Cu3(btc)2 nanocubes via facile interfacial synthesis and an effective dip-coating method. One interesting finding is that 2D arrays of Cu3(btc)2 nanocubes at oil-water interfaces can be transferred on amino-functionalized graphene paper, leading to a densely packed monolayer of Cu3(btc)2 nanocubes with a uniform size loaded on the paper electrode. The electrode demonstrates a variety of excellent sensing performances toward sweat lactate and glucose and has been applied in a non-enzymatic electrochemical biosensing platform for the first time. The modular nature of this approach to assembling MOF nanocrystals will provide new insight into the design of MOF-based electrodes for a wide range of applications in biosensing instruments, wearable electronics, and lab-on-a-chip devices.

Human sweat contains vast physiological information, which has been a promising resource for on‐body and real‐time health monitoring. Wearable sweat sensors have recently attracted an ever‐increasing interest due to their promising capabilities for continuously tracking changes in health status. However, the commercialization of sweat sensors is seriously hindered by drawbacks of materials including high manufacturing and consumables costs, complex integration technology, as well as limited electrochemical signal transduction. In this review, sweat sensing principles are elaborately interpreted, and the latest advances in functional materials for biomarkers sensing in sweat are systematically summarized. Subsequently, the complex structure–activity relationships between various functional materials and sensing capabilities are further elucidated by coupling chemical structures, geometrics, electrochemical properties, and approaches for materials manufacturing. Furthermore, the integration of each component into sensing device for sweat detection and analysis is also discussed. Finally, challenges and opportunities for wearable sweat sensors are delineated in the development of future personalized and predictive healthcare.