Human eyes possess exceptional image sensing characteristics such as spectacularly wide field of view (FOV), high resolution and sensitivity with low aberration. Biomimetic eyes with the same superior characteristics are highly desirable in many technological applications. However, the spherical nature of biological eyes, particularly the core component of retina, poses an enormous challenge for fabrication of biomimetic eyes. Herein, we demonstrate a unique biomimetic electrochemical eye using a hemispherical retina made of high-density array of nanowires mimicking photoreceptors on a real retina. The device design has a high degree of structural similarity to a real human eye with potency to achieve a high imaging resolution when individual nanowires are electrically addressed. Meanwhile, image sensing function of our biomimetic eye device is also demonstrated. The work here may lead to a new generation of photosensing and imaging devices based on a bioinspired design that can benefit a wide spectrum of technological applications.

A combined treatment using medication and electrostimulation increases its effectiveness in comparison with one treatment alone. However, the organic integration of two strategies in one miniaturized system for practical usage has seldom been reported. This article reports an implantable electronic medicine based on bioresorbable microneedle devices that is activated wirelessly for electrostimulation and sustainable delivery of anti-inflammatory drugs. The electronic medicine is composed of a radio frequency wireless power transmission system and a drug-loaded microneedle structure, all fabricated with bioresorbable materials. In a rat skeletal muscle injury model, periodic electrostimulation regulates cell behaviors and tissue regeneration while the anti-inflammatory drugs prevent inflammation, which ultimately enhance the skeletal muscle regeneration. Finally, the electronic medicine is fully bioresorbable, excluding the second surgery for device removal.

In the process of upgrading energy storage structures, sodium‐ion batteries (SIBs) are regarded as the most promising candidates for large‐scale grid storage systems. However, the difficulty in further improving their specific capacity and lifespan has become a major obstacle to promoting extensive application. Herein, by optimizing synthesis conditions, a biphasic‐Na2/3Ni1/3Mn2/3O2 cathode that exhibits an ultrahigh capacity of ≈200 mAh g‐1 without the involvement of anion redox reactions is successfully synthesized. Nevertheless, there is significant electrochemical performance degradation because of failure at the cathode‐electrolyte interface as revealed by comprehensive analyses. Further in‐depth research proves that the surface side reactions that occur at high operating voltages and the transition metal dissolution that occurs in low voltage are the root causes of electrode surface failure. Therefore, the metal oxide atomic layer deposition (ALD) protective layer is deliberately chosen to suppress such failures. The coating effectively blocks corrosion of the cathode material by the electrolyte and successfully anchors the transition metal ions on the particle surface. As a result, the cycle stability and rate performance of the electrode are improved considerably. This surface engineering strategy could provide concepts with broad applicability for suppressing the failure of sodium layered cathodes.