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Aqueous zinc‐iodine (Zn─I2) battery is a promising energy storage system due to its inherent safety, high theoretical capacity, sustainability, and cost‐effectiveness. However, the shuttle effect of polyiodide severely affects the stable loading of active iodine and even accelerates the corrosion of the Zn anode, thus impeding its further advancement. Herein, a unique trimethylsulfonium cation (TMS+) with strong adsorption is proposed to stabilize both the iodine cathode and Zn anode. Benefiting from the robust interaction between TMS+ and polyiodide, the electrolyte can effectively immobilize large‐capacity iodine in the form of oily precipitate, thus avoiding the shuttle effect of polyiodide and the Zn corrosion. Additionally, TMS+ can be preferentially adsorbed on various Zn facets, inducing an electrostatic shielding effect to inhibit Zn dendrite growth. Consequently, Zn anode can be stably cycled over 3400 h at 5 mA cm−2/5 mAh cm−2, and a large areal capacity of 2.71 mAh cm−2 as well as long‐life stability over 6400 cycles is achieved for Zn─I2 battery. Furthermore, cation adsorption engineering is practically utilized in pouch cells, realizing superior fast‐charging stability over 790 cycles. This electrolyte modification with dual stabilizations is anticipated to be applied to other metal‐iodine batteries as a cost‐effective, facile, and safe strategy. [ABSTRACT FROM AUTHOR]

For microelectronic devices, the on‐chip microsupercapacitors with facile construction and high performance, are attracting researchers' prior consideration due to their high compatibility with modern microsystems. Herein, we proposed interchanging interdigital Au‐/MnO2/polyethylene dioxythiophene stacked microsupercapacitor based on a microfabrication process followed by successive electrochemical deposition. The stacked configuration of two pseudocapacitive active microelectrodes meritoriously leads to an enhanced contact area between MnO2 and the conductive and electroactive layer of polyethylene dioxythiophene, hence providing excellent electron transport and diffusion pathways of electrolyte ions, resulting in increased pseudocapacitance of MnO2 and polyethylene dioxythiophene. The stacked quasi‐solid‐state microsupercapacitors delivered the maximum specific capacitance of 43 mF cm−2 (211.9 F cm−3), an energy density of 3.8 μWh cm−2 (at a voltage window of 0.8 V) and 5.1 μWh cm−2 (at a voltage window of 1.0 V) with excellent rate capability (96.6% at 2 mA cm−2) and cycling performance of 85.3% retention of initial capacitance after 10 000 consecutive cycles at a current density of 5 mA cm−2, higher than those of ever reported polyethylene dioxythiophene and MnO2‐based planar microsupercapacitors. Benefiting from the favorable morphology, bilayer microsupercapacitor is utilized as a flexible humidity sensor with a response/relaxation time superior to those of some commercially available integrated microsensors. This strategy will be of significance in developing high‐performance on‐chip integrated microsupercapacitors/microsensors at low cost and environment‐friendly routes. [ABSTRACT FROM AUTHOR]

Miniaturized energy storage devices with superior performance and compatibility with facile fabrication are highly desired in smart microelectronics. Typical fabrication techniques are generally based on powder printing or active material deposition, which restrict the reaction rate due to the limited optimization of electron transport. Herein, we proposed a new strategy for the construction of high-rate Ni-Zn microbatteries based on a 3D hierarchical porous nickel (Ni) microcathode. With sufficient reaction sites from the hierarchical porous structure as well as excellent electrical conductivity from the superficial Ni-based activated layer, this Ni-based microcathode is featured with fast-reaction capability. By virtue of facile electrochemical treatment, the fabricated microcathode realized an excellent rate performance (over 90% capacity retention when the current density increased from 1 to 20 mA cm−2). Furthermore, the assembled Ni-Zn microbattery achieved a rate current of up to 40 mA cm−2 with a capacity retention of 76.9%. Additionally, the high reactivity of the Ni-Zn microbattery is also durable in 2000 cycles. This 3D hierarchical porous Ni microcathode, as well as the activation strategy, provides a facile route for the construction of microcathodes and enriches high-performance output units for integrated microelectronics. [ABSTRACT FROM AUTHOR]

Miniaturized powering devices with both sufficient capacity as well as fast charging capability are anticipated to support microelectronics with multi-functions. However, most reported miniaturized energy storage devices only display limited performances around capacity or rate performance, and it remains challenging to develop high-rate microdevices with large capacities. Herein, a reconstructed NiCo alloy is proposed as a promising microcathode for a Ni-Zn microbattery with a high-rate performance and large capacity. With the reconstructed layer compactly adhered on the metal substrate, the activated NiCo alloy demonstrates an excellent conductivity close to metals. Meanwhile, the abundant alloying defect contributes to a relatively higher reconstruction depth up to 20 nm. Both the superior electron transport and the higher reaction depth facilitate the simultaneous excellent performance in the reaction rate and capacity. As a consequence, the microcathode achieves a large capacity up to 1.51 mAh cm−2, as well as an excellent rate performance with a capacity retention of 82.9% when the current density is expanded to 100 mA cm−2. More surprisingly, such excellent performance can shift towards the full Ni-Zn microbattery, and the fast-charging capability based on large capacity can stably maintain 7000 cycles. This unique strategy of reconstructed NiCo alloy microcathode provides a new direction for the construction of high-performance output units. [ABSTRACT FROM AUTHOR]

Two-dimensional MXenes have become a crucial topic in the field of ion transportation owing to their excellent electrochemical performance. Herein, a strategy for preparing a layered MXene–graphene oxide (GO) membrane via vacuum filtration is proposed, which endows the delaminated two-dimensional MXene–GO membrane (MGOm) with excellent electrical conductivity and chemical stability, achieving an excellent voltage-gated ion transport behavior. Owing to the presence of charges or dipoles within the membrane's channel, the movement of electrons or dipoles under the influence of membrane potential is possible. By varying the transmembrane potential, the transition between the closed and open states of the voltage-gated ion channel can be adjusted. When a negative potential is applied at osmotic pressure, the force between the charged MGOm sheet and the cation (K+) is enhanced, promoting ion permeation. Conversely, the application of positive potential attenuates electrostatic attraction, resulting in a decrease in ion permeability. In addition, the effects of MXene and GO with different modulation ratios on the voltage-gated ion transport have shown that when the modulation ratio of MXene : GO is 7 : 3, the optimal ion permeation rate is achieved. In conclusion, the conductive film with voltage-gated nanochannels is a promising alternative for ion transportation, opening up new avenues for the further exploration of MXene materials in energy storage devices. [ABSTRACT FROM AUTHOR]

In this work, we demonstrated a novel and low-cost full-range optical coherence tomography (FROCT) method. In comparison with the off-pivot approach, which needs precise control of the deflecting distance and should be adjusted for different situations, our proposed method is more flexible without regulating the system itself. Different from the previous systems reported in the literature, which used a high-cost piezo-driven stage to introduce the phase modulation, our system utilizes a cost-effective voice coil motor for retrieving the complex-valued spectral signal. The complex-valued data, with a twofold increase in the accessible depth range, can be calculated using an algorithm based on the Hilbert transform and Dirac delta function. To confirm the effectivity of our method, both simulation and experiments were performed. In particular, for the in vivo experiment, we presented the FROCT result of a fingernail fold, demonstrating the availability of in vivo imaging. Since the key element of our system is a low-cost voice coil motor, which is flexible and more accessible for most of the clinics, we believe that it has great potential to be a clinical modality in the future. [ABSTRACT FROM AUTHOR]

The aspheric light emitted from a pinhole restrains the reconstruction quality of a digital in-line hologram. Herein, the Fresnel-diffracted spot from the first step converging spherical wave diffracted at a rough circular aperture is collimated and expanded to generate an even plane wave, which is converged again by an objective lens and matching a minimum aperture while the central spot is varying from light to dark. We observed that the collected background hologram is filled with a round spot with high contrast as an ideal spherical wave. The resolution board and biology experimental results demonstrated a distinctively reconstructed image without any image processing in a single exposure. The adjustable field of view and magnification, single exposure, and noncontact make it suitable for an online microscope. [ABSTRACT FROM AUTHOR]