The fabrication of non‐noble element electrocatalysts with comparable catalytic activity with Pt‐based materials is in great requirements for water splitting to achieve sustainable hydrogen production. Cu2S/MoS2 heterojunction nanorod arrays on copper foam were prepared for this purpose. The nitrogen doping was achieved in situ. HRTEM, SEM, XPS and EDX verified the heterojunction interfacial texture and the defect‐rich nanoarray configuration. The heterojunction interfacial texture, the defect rich configuration and the outward active sites optimized the structure required as a high‐efficient hydrogen evolution reaction (HER) electrocatalyst. As a result, the charge transfer resistance of the nanoarrays was estimated to be 5.4 Ω at −200 mV versus RHE, even lower than both the precursors. The electrochemical double layer capacitance was 49.95 mF cm−2, which was higher than both the precursors. The Cu2S/MoS2 heterojunction nanoarrays‐like electrocatalyst exhibited significant performance with a low overpotential (91 mV at 10 mA cm−2) and a small Tafel slope (41 mV dec−1) in alkaline electrolyte with 85.3 % retained ability after 1000 cycle runs. This work paves a road for developing high‐performance HER electrocatalysts.

The stepwise electrodeposition of Ni/Ni(OH)2 dual composition resulted in 3D hierarchical nanoarrays with a papillae-like hybrid crystal structure.

robots, [3] actuators, [4] etc. Among them, zwitterionic hydrogels have recently attracted tremendous attention due to their exceptional electrical properties and special biological functions, boosting progress in energy storage and biomedical applications. [5] In particular, polybetaines, bearing a pair of cationic and anionic groups in their repeating units, exhibit equal charge stoichiometry and uniform charge distribution at the molecular level. The homogenously distributed dynamic ionic bonds within the polybetaine hydrogels contribute to an efficient and rapid self-healing capability, which allows for significant deformations and autorecovery after injury during their service life. Such characteristics make polybetaine hydrogels uniquely competitive in a wide range of applications. [6] The humidity and temperature in living environment varies greatly, roughly 30-90% relative humidity (RH) and −20 to 40 °C, [7] therefore, wide-humidity range applicable and freeze-resistant hydrogels are very crucial in order to achieve reliable applications at ambient conditions. Hydrogels tend to dry out when exposed to dry environments, [8] freeze at low temperatures, [9] and swell due to water absorption in high humidity environments, [10] all of which severely affect their properties, thus limiting further applications of hydrogels in flexible electronic devices. Various methods have been reported to improve the water retention and freezing tolerance of hydrogels. Encapsulating the hydrogels can effectively prevent the Hydrogels have entered the spotlight for applications in soft electronics. It is essential and challenging to obtain hydrogels that can function properly under varying environmental circumstances, that is, 30-90% relative humidity (RH) and −20 to 40 °C due to their intrinsic nature to lose and absorb water upon variations in humidity and temperature. In this work, a green solvent, solketal, is introduced into poly 3-dimethyl-2-(2-methylprop-2-enoyloxy)ethyl azaniumyl propane-1-sulfonate (poly(DMAPS)) zwitterionic hydrogels. Compared to glycerol, solketal endows hydrogels with greater possibility for further modification as well as improved water content and mechanical performance consistency over 30-90% RH. Encouragingly, the optimized hydrogel demonstrates its unique merits as a dielectric layer in iontronic sensors, featuring non-leaky ions, high sensitivity (1100 kPa −1 ), wide humidity, and temperature range applicability. A wide-humidity range healable and stretchable electrode is attained by combining the hydrogel substrate with Ag paste. A full-device healable and highly-sensitive sensor is developed. This study is a pioneering work that tackles the broad humidity range applicability issue of hydrogels, and demonstrates the ion-leakagefree ionic skins with zwitterionic dielectrics. The outcomes of the study will considerably promote advancements in the fields of hydrogel electronics and iontronic sensors.

Smart windows nowadays undertake the esteemed obligation of reducing energy consumption as well as upgrading living experience. This project aims to devise a smart window that responds to both electricity and heat, with the intention of achieving energy efficiency, privacy preservation, and enhanced decorative attributes. Through the implementation of a novel electrochromic material design, coupled with the optimization of electrochromic devices (ECDs), a high‐performance ECD is obtained, demonstrating coloring/bleaching time of 0.53/0.16 s, a transmittance modulation of 78% (from 99% to 21%), and superior performance in six dimensions. Furthermore, temperature‐responsive units and an ionic liquid are incorporated into the electrolyte system to create a novel thermochromic gel electrolyte with transmittance modulation from 80% to 0%, and excellent thermal insulation (6.4 °C reduction). Ultimately, an electro‐ and thermochromic device is developed, featuring an ultrafast color‐switching speed of 0.82/0.60 s and multiple working modes. Overall, this work showcases a prospective design pathway for the development of next‐generation ultrafast‐switching, and energy‐efficient intelligent windows.