Based on the triboelectrification and electrostatic induction coupling, triboelectric nanogenerators (TENGs) can convert mechanical energy into electrical energy, showing a promising potential in the fields of micro/nano energy and self-powered sensors applications. However, the devices are prone to malfunction due to fatigue and damage, limiting their development and applications. In this review, according to the working modes and operational malfunctions as well as the possible solutions, it is proposed that a robust TENG device can be constructed from three perspectives: self-healing friction layers, self-healing electrodes, and self-healing whole devices. Based on the structure, suitable environment, and self-healing materials, the design ideas and fabrication approaches of self-healing TENGs in recent years are summarized in detail. Finally, the development of self-healing TENGs in energy harvesting and self-powered sensors is outlined. It is the wish to provide insights and guidance for the application design of self-healing TENGs in the future.

The employment of intermediate layer technology to improve the mechanical stability of superhydrophobic coatings (SHCs) is an acknowledged tool, but the mechanism by which intermediate layers, especially different ones, affect superhydrophobic composite coatings is not clear. In this work, a series of SHCs based on the strengthening of the intermediate layer were fabricated by employing polymers with different elastic moduli such as polydimethylsiloxane (PDMS), polyurethane (PU), epoxy (EP) resin, as well as graphite/SiO2 hydrophobic components. Following that, the effect of different elastic modulus polymers as an intermediate layer on the durability of SHCs was investigated. From the perspective of elastic buffering, the strengthening mechanism of elastic polymer-based SHCs was clarified. Furthermore, from the perspective of self-lubrication, the wear resistance mechanism of self-lubricating hydrophobic components in the SHCs was elucidated. Also, the prepared coatings exhibited excellent acid and alkali resistance, self-cleaning, anti-stain, and corrosion resistance. This work confirms that low-elastic-modulus polymers can also play the role of buffering external impact energy by elastic deformation even as an intermediate layer, and provides theoretical guidance for the development of SHCs with robustness.

Self-healing triboelectric nanogenerators (TENGs) are new, stable and durable energy harvesters. Polyimide (PI) is a promising negatively charged material that has been widely developed as a negative friction material for TENGs, but self-healing PI-based TENGs are currently vacant. Here, we reported a self-healing TENG device fabricated by self-healing PI for energy harvesting and motion sensing. The designed and fabricated PI-based TENGs exhibited excellent intrinsic self-healing and shape tailorability properties. The self-healing properties are derived from the dynamic disulfide bond exchange and flexible PDMS fragments in the PI backbone, which can recover its damage and output performance at 100 degrees C for 3 h. The output performance of the fabricated 6FDA-4PDA-PDMS-PI-based TENG was double that of the normal PI-based TENG due to CF3 electron-absorbing groups and siloxane fragments in the PI backbone. Finally, the applications of self-healing PI-based TENGs to harvest energy to drive commercial electronic devices and joint motion sensing were demonstrated. This work provides theoretical guidance for the fabrication of self-healing TENGs with reliable output performance and practical applications, contributing to the future of sustainable energy and wearable electronics.

Inspired by the lotus leaf effect,non-wetting artificial superhydrophobic surfaces demonstrate an enor-mous potential in numerous fields.However,limited by poor stability and durability,superhydrophobic surfaces are rarely available for practical applications.In this review,based on the wettability mechanisms and failure modes of superhydrophobic surfaces,it is proposed that the construction of highly stable superhydrophobic materials can be approached from four aspects,including structural design,chemical bonding,interfacial-strengthening of hydrophobic materials and substrates,and self-healing.We intro-duced in detail the design ideas,strengthening approaches,and characterization tools of highly stable su-perhydrophobic materials from the perspective of multi-strategy design and strengthening,and provided corresponding insights.Eventually,the development,current status,and prospects of highly stable and multifunctional superhydrophobic materials were also presented in detail.Recent advances and develop-ment prospects of durable superhydrophobic materials were summarized and discussed in this review,providing certain insights and design guidelines for the fabrication of stable superhydrophobic materials.

Synergistic self-healing materials and inorganic particles to create self-healing superhydrophobic surfaces for improving their robustness is a common technique, but the suitability between the two is rarely mentioned. In this work, we developed a multifunctional superhydrophobic coating with room-temperature stability, mechanical stability, self-healing, and NIR stimuli response, in which self-healing polyurethane (PU) serves as the interface reinforcement layer and poly(dopamine) (PDA)-coated flower-like ZnO composite particles serve as the hydrophobic layer. A series of temperature-dependent self-healing PU materials were designed and synthesized by regulating the ratio of hard and soft chain segments in PU, and the relationship between the healing temperature of PU and the hydrophobic stability of the composite coatings was investigated. Based on dynamic hydrogen and disulfide bonds, PUs displayed excellent self-healing performance. Thanks to the self-healing and interfacial strengthening effect of PU and the photothermal properties of PDA, the composite coating exhibits not only excellent mechanical stability but also rapid self-healing ability in response to NIR stimuli. Furthermore, the smart coating demonstrated superior self-cleaning and corrosion resistance. This work provides a reference for developing strong and stable water-repellent reversible superhydrophobic coatings with great potential and promising future.

Co-working by lotus-leaf effect and self-healing shows a great potential against marine corrosion as it could form a barrier capable of water repelling and microdefect healing on the substrate. We developed a firm and self-healing superhydrophobic coating (SHC) technology, in which carbon steel substrate was first coated with fluoroethylene vinyl ether resin/polycaprolactone (FEVE/PCL) hybrid resin, and then sprayed with SiO2. Results showed that the hybrid resin could strengthen the interface between the SiO2 layer and the substrate and could heal microdefect due to the thermal exudation effect of PCL, and consequently form a corrosion barrier. The SHC exhibited great water resistance, stability, and durability. This dual-layered coating performed excellently in corrosion prevention. With the thermal exudation effect of PCL, the dual-layered coating could quickly recover its superhydrophobicity and corrosion resistance under thermal stimuli, making it possible to protect metal substrate persistently. Therefore, this approach provides an easy technique against marine corrosion with water repelling and scratch-healing ability, and shall be promising for long-term corrosion protection.

Discovery of intrinsic two-dimensional (2D) magnetic materials is crucial for understanding the fundamentals of 2D magnetism and realizing next-generation magnetoelectronic and magneto-optical devices. Although significant efforts have been devoted to identifying 2D magnetism by exfoliating bulk magnetic layered materials, seldom studies are performed to synthesize ultra-thin magnetic materials directly for non-layered magnetic materials. Here, we report the successful synthesis of a new type of theoretically proposed 2D metallic ferromagnet 1T FeS2, through the molten-salt-assisted chemical vapor deposition (CVD) method. The long-range 2D ferromagnetic order is confirmed by the observation of a large anomalous Hall effect (AHE) and a hysteretic magnetoresistance. The experimentally detected out-of-plane ferromagnetic ordering is theoretically suported with Stoner criterion. Our findings open up new possibilities to search novel 2D ferromagnets in non-layered compounds and render opportunities for realizing realistic ultra-thin spintronic devices.

The coalescence-induced droplet self-jumping behavior on superhydrophobic surfaces (SHS) provides a new idea for atmospheric corrosion prevention. Although the influence on droplet self-jumping on different scales in single structure has been well understood, the mechanism of composite structures on droplet self-jumping, especially the process of atmospheric corrosion prevention is still unclear. Therefore, SHS that composite structured on micron-scale and nano-scale were designed on copper substrate at given salt solution concentration using hydrothermal method; and the difference of their droplet self-jumping behavior on surface was explored in energy perspective. Results showed that the nano-scale composite structured SHS was more conducive to droplet self-jumping for having smaller top layer structures and interfacial adhesion ( E int ). Furthermore, the nano-scale composite structured SHS exhibited superior corrosion protection performance due to the wetting transition by droplet self-jumping. This study provides theoretical guidance for the development of corrosion prevention with composite structured SHS based on coalescence-induced droplet self-jumping behavior.

Bioinspired superhydrophobic surfaces (SHS) have potential application prospects in many fields, but weak mechanical stability of the microstructures has become the main bottleneck. In this work, the water-glass strengthened the interfacial force between the inorganic SiO 2 and ZnO particles and the substrate through chemical reaction rather than physical embedding, which obtains a robust superhydrophobic surface. Based on surface characterization and analysis, the mechanism of the water-glass that played a role of enhancing the interface between the particles and the substrate in the coating was explored and proposed. Furthermore, the effect of the treatment temperature on the surface structure of the water-based paint during the spraying process was studied. Through simulating different environments, the anti-acid and -alkali resistance and anti-aging ability were tested in the full pH range or under strong UV irradiation, showing an excellent performance. Different mechanical stability tests confirmed that the silicate network structure enhances the binding force between the particles, improving the robustness of the superhydrophobic surface. This work may provide a new insight for the construction of superhydrophobic surfaces with enhanced interfaces.

Weyl nodes and Fermi arcs in type-II Weyl semimetals (WSMs) have led to lots of exotic transport phenomena. Recently, Mo_0.25W_0.75Te_2 has been established as a type-II WSM with Weyl points located near Fermi level, which offers an opportunity to study its intriguing band structure by electrical transport measurements. Here, by selecting a special sample with the thickness gradient across two- (2D) and three-dimensional (3D) regime, we show strong evidences that Mo_0.25W_0.75Te_2 is a type-II Weyl semimetal by observing the following two dimensionality-dependent transport features: 1) A chiral-anomaly-induced anisotropic magneto-conductivity enhancement, proportional to the square of in-plane magnetic field (B_in^2); 2) An additional quantum oscillation with thickness-dependent phase shift. Our theoretical calculations show that the observed quantum oscillation originates from a Weyl-orbit-like scenario due to the unique band structure of Mo_0.25W_0.75Te_2. The in situ dimensionality-tuned transport experiment offers a new strategy to search for type-II WSMs.

Superhydrophobic surfaces (SHS) have potential application prospects in many fields for the lotus effect. The microdroplet self-propelling effect is a newly discovered mechanism of SHS phenomena, which provides more possibilities for SHS applications. In this study, the ZnO-nanoneedle array was designed and constructed by an electrodeposition method. Based on surface characterization and analysis, the nucleation, growth, and merging process of SHS surface droplets under simulated condensation conditions were studied. The correlation between the surface microstructure and the jumping behavior was established, and the self-propelling mechanism was analyzed from an energy perspective. Based on electrochemical data, the contribution of self-propelling behavior to the atmospheric corrosion protection performance of SHS was analyzed, which confirms that the droplet self-propelling behavior, as a new SHS atmospheric corrosion protection mechanism, has potential applications in atmospheric corrosion protection in the future.

Recently, new states of matter like superconducting or topological quantum states were found in transition metal dichalcogenides (TMDs) and manifested themselves in a series of exotic physical behaviors. Such phenomena have been demonstrated to exist in a series of transition metal tellurides including MoTe2, WTe2, and alloyed MoxW1-xTe2. However, the behaviors in the alloy system have been rarely addressed due to their difficulty in obtaining atomic layers with controlled composition, albeit the alloy offers a great platform to tune the quantum states. Here, we report a facile CVD method to synthesize the MoxW1-xTe2 with controllable thickness and chemical composition ratios. The atomic structure of a monolayer MoxW1-xTe2 alloy was experimentally confirmed by scanning transmission electron microscopy. Importantly, two different transport behaviors including superconducting and Weyl semimetal states were observed in Mo-rich Mo0.8W0.2Te2 and W-rich Mo0.2W0.8Te2 samples, respectively. Our results show that the electrical properties of MoxW1-xTe2 can be tuned by controlling the chemical composition, demonstrating our controllable CVD growth method is an efficient strategy to manipulate the physical properties of TMDCs. Meanwhile, it provides a perspective on further comprehension and sheds light on the design of devices with topological multicomponent TMDC materials.

Improving the mechanical stability and oil stability of slippery liquid infused porous surface (SLIPS) is very urgent to its long-term application in preventing bacteria settlement and mitigating the following microbiologically influenced corrosion (MIC) for metallic material in marine environment. Herein, a robust superhydrophobic surface was first fabricated through spraying SiO2 nanoparticles on the natural resin shellac adhesive. The superhydrophobic surface could retain superhydrophobicity after 160 sandpaper abrasion cycles (abrasive length of 64 m), which was attributed to the strong binding force between SiO2 nanoparticles and shellac via hydrogen bonding. Thus, a robust SLIPS was fabricated through infusing lubricant oil into abrasion-resistant superhydrophobic surface. And the fabricated slippery surface exhibited stable slippery performance after spin treatment and damaged by a scratch. Furthermore, scanning kelvin probe (SKP) test verified the scratch was able to heal through the self-healing performance of lubricant oil. Finally, the bacterial settlement and electrochemical experiment results indicated the SLIPS could effectively mitigate sulfate reducing bacteria (SRB) settlement and following MIC after immersing in SRB solution for 14 days. This facile method provides a guidance to fabricate robust slippery surface for its long term application.

Many proposals for exploring topological quantum computation are based on superconducting quantum devices constructed on materials with strong spin-orbit coupling (SOC). For these devices, full control of both the magnitude and the spatial distribution of the supercurrent is highly demanded, but has been elusive up to now. We constructed a proximity-type Josephson junction on nanoplates of Bi2O2Se, a new emerging semiconductor with strong SOC. Through electrical gating, we show that the supercurrent can be fully turned ON and OFF, and its real-space pathways can be configured either through the bulk or along the edges. Our work demonstrates Bi2O2Se as a promising platform for constructing multifunctional hybrid superconducting devices as well as for searching for topological superconductivity.

Two-dimensional transition metal dichalcogenides MX 2 ( M = W, Mo, Nb, and X = Te, Se, S) with strong spin–orbit coupling possess plenty of novel physics including superconductivity. Due to the Ising spin–orbit coupling, monolayer NbSe 2 and gated MoS 2 of 2 H structure can realize the Ising superconductivity, which manifests itself with in-plane upper critical field far exceeding Pauli paramagnetic limit. Surprisingly, we find that a few-layer 1 T d structure MoTe 2 also exhibits an in-plane upper critical field which goes beyond the Pauli paramagnetic limit. Importantly, the in-plane upper critical field shows an emergent two-fold symmetry which is different from the isotropic in-plane upper critical field in 2 H transition metal dichalcogenides. We show that this is a result of an asymmetric spin–orbit coupling in 1 T d transition metal dichalcogenides. Our work provides transport evidence of a new type of asymmetric spin–orbit coupling in transition metal dichalcogenides which may give rise to novel superconducting and spin transport properties.

Ziyi Liu,1,2 Wei Wu,1,3,4,* Zhenzheng Zhao,1 Hengcan Zhao,1,4 Jian Cui,1 Pengfei Shan,1 Jiahao Zhang,1,4 Changli Yang,1,5 Peijie Sun,2 Yuan Wei,1,4 Shiliang Li,1,3 Jinggeng Zhao,2 Yu Sui,2 Jinguang Cheng,1,3 Li Lu,1,5,3 Jianlin Luo,1,5,3,† and Guangtong Liu1,3,‡ 1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China 2Department of Physics, Harbin Institute of Technology, Harbin, Heilongjiang 150001, China 3Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China 4University of Chinese Academy of Sciences, Beijing 100049, China 5Collaborative Innovation Center of Quantum Matter, Beijing 100871, China

The strong spin$-$orbit coupling (SOC) and numerous crystal phases in few$-$layer transition metal dichalcogenides (TMDCs) MX$_2$ (M$=$W, Mo, and X$=$Te, Se, S) has led to a variety of novel physics, such as Ising superconductivity and quantum spin Hall effect realized in monolayer 2H$-$ and Td$-$MX$_2$, respectively. Consecutive tailoring of the MX$_2$ structure from 2H to Td phase may realize the long$-$sought topological superconductivity in one material system by incorporating superconductivity and quantum spin Hall effect together. In this work, by combing Raman spectrum, X-ray photoelectron spectrum (XPS), scanning transmission electron microscopy imaging (STEM) as well as electrical transport measurements, we demonstrate that a consecutively structural phase transitions from Td to 1T$'$ to 2H polytype can be realized as the Se-substitution concentration increases. More importantly, the Se$-$substitution has been found to notably enhance the superconductivity of the MoTe$_2$ thin film, which is interpreted as the introduction of the two$-$band superconductivity. The chemical constituent induced phase transition offers a new strategy to study the s$_{+-}$ superconductivity and the possible topological superconductivity as well as to develop phase$-$sensitive devices based on MX$_2$ materials.

We report the discovery of superconductivity in high-quality single crystals of transition-metal pnictides WP grown by chemical vapor transport method. Bulk superconductivity is observed at T-c similar to 0.8 K at ambient pressure by electrical resistivity, ac magnetic susceptibility, and specific-heat measurements. The effects of magnetic field on the superconducting transitions are studied, leading to a large anisotropy parameter around 2 with the in-plane and out-of-plane upper critical fields of mu H-0(c2,parallel to) = 17.2 mT and mu H-0(c2,perpendicular to) = 8.5 mT, respectively. The low value of electron-phonon coupling estimated from the normal-state resistivity and specific-heat measurements suggest that WP is a weak-coupling BCS superconductor. Our finding demonstrates that WP is the first superconductor among 5d-transition metal pnictides with MnP-type structure at ambient pressure, which will help in the search for new superconductors in transition-metal pnictides.

We report on magnetoresistance, Hall effect, and quantum Shubnikov–de Haas oscillation (SdH) experiments in NbIrTe 4 single crystals, which was recently predicted to be a type-II Weyl semimetal. NbIrTe 4 manifests a non-saturating and parabolic magnetoresistance at low temperatures. The magneto-transport measurements show that NbIrTe 4 is a multiband system. The analysis of the SdH oscillations reveals four distinct oscillation frequencies. Combined with the density-functional theory calculations, we show that they come from two types of Fermi surfaces: electron pocket E 1 and hole pocket H 2 .