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The balance between degradability and drug release kinetics is a major challenge for the development of drug delivery systems. Here we develop hierarchically structured nanoparticles comprising multiple noncontact silica shells using an amorphous calcium carbonate template. The system could be degraded in a sequential fashion on account of the molecularly engineered multishelled structures. The hydrolysis rate of drug-containing cores is inversely correlated with the nanoparticle concentration due to the shielding effect of the hierarchical nanostructure and could be exploited to regulate the release kinetics. Specifically, multishelled nanospheres show a low drug release rate with high doses that increases steadily as the concentration decreases due to continuous degradation, thus stabilizing the local drug concentration for effective tumor therapy. Moreover, the nanoparticles could be eventually degraded completely, which may reduce their health risks. This kind of hierarchically structured silica-based nanoparticle could serve as a sustainable drug depot and provides a new avenue for tumor treatment.

The photothermoelectric effect, directly converting light energy into electrical energy, shows promising prospects in self-powered broad-band optical detection, which can extend to various applications, such as sensing, optoelectronic communications, and wide-temperature-range measurements. However, the low photosensitivity, narrow-band response, and rapid performance degeneration under continuous illumination restrict its broad application. Herein, we propose a simple bottom-up strategy to manipulate nanowires (NWs) into a well-defined multilayer Te-Ag

High-performance functional fibers play a critical role in various indispensable fields, including sensing, monitoring, and display. It is desirable yet challenging to develop conductive fibers with excellent mechanical properties for practical applications. Herein, inspired by the exquisite fascicle structure of skeletal muscle, we constructed a high-performance bacterial cellulose (BC)/carbon nanotube (CNT) conductive fiber through in situ biosynthesis and enhancement of structure and interaction. The biosynthesis strategy achieves the in situ entanglement of CNTs in the three-dimensional network of BC through the deposition of CNTs during the growth of BC. The structure enhancement through physical wet drawing and the interaction enhancement through chemical treatment facilitate orientation and bridging of components, respectively. Owing to the ingenious design, the obtained composite fibers integrate high strength (939 MPa), high stiffness (52.3 GPa), high fatigue resistance, and stable electrical performance, making them competitive for constructing fiber-based smart devices for practical applications.

Picturing the atomic migration pathways of catalysts in a reactive atmosphere is of central significance for uncovering the underlying catalytic mechanisms and directing the design of high-performance catalysts. Here, we describe a reduction-controlled atomic migration pathway that converts nanoparticles to single atom alloys (SAAs), which has remained synthetically challenging in prior attempts due to the elusive mechanism. We achieved this by thermally treating the noble-metal nanoparticles M (M = Ru, Rh, Pd, Ag, Ir, Pt, and Au) on metal oxide (CuO) supports with H

Humans rely increasingly on sensors to address grand challenges and to improve quality of life in the era of digitalization and big data. For ubiquitous sensing, flexible sensors are developed to overcome the limitations of conventional rigid counterparts. Despite rapid advancement in bench-side research over the last decade, the market adoption of flexible sensors remains limited. To ease and to expedite their deployment, here, we identify bottlenecks hindering the maturation of flexible sensors and propose promising solutions. We first analyze challenges in achieving satisfactory sensing performance for real-world applications and then summarize issues in compatible sensor-biology interfaces, followed by brief discussions on powering and connecting sensor networks. Issues en route to commercialization and for sustainable growth of the sector are also analyzed, highlighting environmental concerns and emphasizing nontechnical issues such as business, regulatory, and ethical considerations. Additionally, we look at future intelligent flexible sensors. In proposing a comprehensive roadmap, we hope to steer research efforts towards common goals and to guide coordinated development strategies from disparate communities. Through such collaborative efforts, scientific breakthroughs can be made sooner and capitalized for the betterment of humanity. Agency for Science, Technology and Research (A*STAR) National Research Foundation (NRF) Submitted/Accepted version Y.L., Z.L., M.Z., and X.C. acknowledge the National Research Foundation, Singapore (NRF) under NRF’s Medium Sized Centre: Singapore Hybrid-Integrated Next-Generation μElectronics (SHINE) Centre funding programme, and AME programming funding scheme of Cyber Physiochemical Interface (CPI) project (no. A18A1b0045). Y.L. acknowledges National Natural Science Foundation of China (62201243). C.J. acknowledges funding support from the National Key R&D Program of China (no. 2019YFA0706100), the National Natural Science Foundation of China (82151305), Lingang Laboratory (LG-QS-202202-09). T.Q.T. and N.E.L. acknowledge support by the Basic Science Research Program (no. 2020R1A2C3013480) through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT. A.F. acknowledges the AFOSR (grant FA9550-22-1-0423). Y.L. and Y.Z. would like to acknowledge the NSF (award no. 2134664) and NIH (award no. R01HD108473) for financial support. X.F. acknowledges the support from the National Natural Science Foundation of China (grant no. U20A6001). L.Y. would like to thank the A*STAR Central Research Fund (CRF) and the AME Programmatic A18A1b0045 (Cyber Physiochemical Interfaces) for funding support. C.F.G. acknowledges the National Natural Science Foundation of China (no. T2225017). T.Q.T. acknowledges the Brain Pool Program (No. 2020H1D3A2A02111068) through the National Research Foundation (NRF) funded by the Ministry of Science. Z.L. acknowledges the support from RIE2020 AME Programmatic Grant funded by A*STAR-SERC, Singapore (Grant No. A18A1b0045). X.G. acknowledges funding support through the Shanghai Science and Technology Commission (grant no. 19JC1412400), the National Science Fund for Excellent Young Scholars (grant no. 61922057). C.D. acknowledges National Science Foundation CAREER: Conformable Piezoelectrics for Soft Tissue Imaging (grant no. 2044688) and MIT Media Lab Consortium funding. D.K. and O.G.S. acknowledge Leibniz Association and the German Research Foundation DFG (Gottfried Wilhelm Leibniz Program SCHM 1298/22-1, KA5051/1-1 and KA 5051/3-1), as well as the Leibniz association (Leibniz Transfer Program T62/2019). C.W. acknowledges the National Key Research and Development Program of China (grant no. 2021YFA1202600), National Natural Science Foundation of China (grant no. 62174082). A.V.-Y.T., E.Z., Y.Z., X.Z., and J.P. acknowledge the National Research Foundation, Singapore (NRF) under NRF’s Medium Sized Centre: Singapore Hybrid-Integrated Next-Generation μElectronics (SHINE) Centre funding programme, and AME programming funding scheme of Cyber Physiochemical Interface (CPI) project (no. A18A1b0045). R.Z. acknowledges National Natural Science Foundation of China (grant no. 51735007) and Beijing Natural Science Foundation (grant no. 3191001). N.M. acknowledges the support by JST PRESTO Grant Number JPMJPR20B7 and JST Adaptable and Seamless Technology transfer Program through Target-driven R&D (ASTEP) grant number JPMJTM22BK. C.P. acknowledges the Korean government (Ministry of Science and ICT, MSIT) (2022R1A4A3032923). M.W. acknowledges the National Key R&D Program of China under Grant (2021YFB3601200). X.Z. acknowledges National Natural Science Foundation of China (no. 62074029). S.X. acknowledges the 3M nontenured faculty award. T.-W.L. and D.-G.S. acknowledge the Pioneer Research Center Program through the National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning (grant no. NRF-2022M3C1A3081211). C.T.L. would like to acknowledge support from the Institute for Health Innovation and Technology (iHealthtech), the MechanoBioEngineering Laboratory at the Department of Biomedical Engineering and the Institute for Functional Intelligent Materials (I-FIM) at the National University of Singapore (NUS). C.T.L. also acknowledges support from the National Research Foundation and A*STAR, under its RIE2020 Industry Alignment Fund − Industry Collaboration Projects (IAF-ICP) (grant no. I2001E0059) − SIA-NUS Digital Aviation Corp Lab and the NUS ARTIC Research (grant no. HFM-RP1). X.Y. acknowledges funding support by City University of Hong Kong (grant no. 9667221). T.X. and X.Z. acknowledge National Natural Science Foundation of China (22234006). B.C.K.T. acknowledges Cyber-Physiochemical Interfaces CPI, A*STAR A18A1b0045. H.G. acknowledges a research start-up grant (002479-00001) from Nanyang Technological University and the Agency for Science, Technology and Research (A*STAR) in Singapore. W.G. acknowledges National Science Foundation grant 2145802. D.J.L. acknowledges support from the US National Science Foundation grant number CBET-2223566. G.Y. acknowledges support from The Welch Foundation award F-1861, and Camille Dreyfus Teacher-Scholar Award. M.D.D. acknowledges funding support from NSF (grant no. EEC1160483). J.-H.A acknowledges the National Research Foundation of Korea (NRF-2015R1A3A2066337). J.C. acknowledges the Henry Samueli School of Engineering & Applied Science and the Department of Bioengineering at the University of California, Los Angeles for startup support and a Brain & Behavior Research Foundation Young Investigator Grant. K.T. acknowledges JST AIP Accelerated Program (no. JPMJCR21U1) and JSPS KAKENHI (grant no. JP22H00594). P.S.W. acknowledges the National Science Foundation (CMMI1636136) for support. A.M.A., M.C.H., and P.S.W. thank the National Institute on Drug Abuse (DA045550) for support. S.M. and X.C. appreciated the support from the Smart Grippers for Soft Robotics (SGSR) Programme under the National Research Foundation, Prime Minister’s Office, Singapore under its Campus of Research Excellence and Technological Enterprise (CREATE) programme.

Skin-mountable capacitive-type strain sensors with great linearity and low hysteresis provide inspiration for the interactions between human and machine. For practicality, high sensing performance, large stretchability, and self-healing are demanded but limited by stretchable electrode and dielectric and interfacial compatibility. Here, we demonstrate an extremely stretchable and self-healing conductor via both hard and soft tactics that combine conductive nanowire assemblies with double dynamic network based on π-π attractions and Ag-S coordination bonds. The obtained conductor outperforms the reported stretchable conductors by delivering an elongation of 3250%, resistance change of 223% at 2000% strain, high durability, and multiresponsive self-healability. Especially, this conductor accommodates large strain of 1500% at extremely knotted and twisted deformations. By sandwiching hydrogel conductors with a newly developed dielectric, ultrahigh stretchability and omni-healability are simultaneously achieved for the first time for a capacitive strain sensor inspired by metal-thiolate coordination chemistry, showing great potentials in wearable electronics and soft robotics.

Softness, adhesion, stretchability, and fast recovery from large deformations are essential properties for conductive elastomers that play an important role in the development of high-performance soft electronics. However, it remains an ongoing challenge to obtain conductive elastomers that combine these properties. We have fabricated a super soft (Young's modulus 2.3-12 kPa), highly stretchable (up to 1500% strain), and underwater adhesive silicone conductive elastomer composite (SF-C-PDMS) by incorporating dimethyl silicone oil as a lubricating agent in a cross-linked molecular network. The resultant SF-C-PDMS not only exhibits superior softness but also can readily recover after a strain of 1000%. The initial resistance only decreases by 8% after 100000 cycles of tensile fatigue test (100% strain, 0.5 Hz, 15 mm/s). This multifunctional silicone conductive elastomer composite is obtained in a one-step preparation at room temperature using commercially available materials. Moreover, we illustrate the capabilities of this composite in motion sensing.

Additive manufacturing (AM) is the key to creating a wide variety of 3D structures with unique and programmable functionalities. Direct ink writing is one of the widely used AM technologies with numerous printable materials. However, the extrude-based method is limited by low fabrication resolution, which is confined to printing macrostructures. Herein, a new AM strategy is reported, using a low-cost extrusion 3D printer, to create 3D microarchitectures at the macroscopic level through controlled desiccation of preprinted hydrogel scaffolds followed by infilling objective components. A printable hydrogel with a high-water content ensures maximum shrinkage (≈99.5% in volume) of the printed scaffolds to achieve high resolution. Stable covalent cross-linking and a suitable drying rate enable uniform shrinkage of the scaffolds to retain their original architectures. Particularly, this method can be adapted to produce liquid-metal-based 3D circuits and nanocomposite-based microrobots, indicating its capability to fabricate functional and complex 3D architectures with micron-level resolution from different material systems.

Direct and rapid printing and surface patterning of hydrogel thin films are of great significance in the construction of advanced electronic devices, yet they are greatly underdeveloped due to the intrinsic contradiction between mechanical strength and self-healability as well as recyclability. Here, we present a universal and rapid slipping-directed route with a newly developed water-soluble star polymer hydrogel for direct and reproducible printing and patterning of freestanding functional thin films with precisely controlled thicknesses, components, and surface structures on a large scale. The resulting thin films combine the features of large transmittance (93%), tough mechanical strength (114 MPa), multiresponsive self-healability, recyclability, and remarkable multifunctionality. With the unique humidity-sensitive properties as motivation, diverse humidity-sensing devices including an actuating switch, a supercapacitive sensor, and a noncontact electronic skin are facilely constructed through the humidity-induced transverse, longitudinal, and patterning assembly techniques, respectively. The method presented here is universal and efficient in the fabrication and assembly of thin films with controlled configuration and functionality for advanced flexible electronics.

Widely used disposable plastic tableware is usually buried or directly discharged into the natural environment after using, which poses potential threats to the natural environment and human health. To solve this problem, nondegradable plastic tableware needs to be replaced by tableware composed of biodegradable structural materials with both food safety and the excellent mechanical and thermal properties. Here, a food-safe sargassum cellulose nanofiber (SCNF) is extracted from common seaweed in an efficient and low energy consuming way under mild reaction conditions. Then, by assembling the SCNF into a dense bulk material, a strong sargassum cellulose nanofiber structural material (SCNSM) with high strength (283 MPa) and high thermal stability (160 °C) can be prepared. The SCNSM also possesses good machinability, which can be processed into tableware with different shapes, e.g., knives and forks. The overall performance of the SCNSM-based tableware is better than commercial plastic, wood-based, and poly(lactic acid) tableware, which shows great application potential in the tableware field.

Conductive and adhesive hydrogels are promising materials for designing bioelectronics. To satisfy the high conductivity of bioelectronic devices, metal nanomaterials have been used to fabricate composite hydrogels. However, the fabrication of a conductive-nanomaterial-incorporated hydrogel with high performance is a great challenge because of the easy aggregation nature of conductive nanomaterials making processing difficult. Here, we report a kind of adhesive aero-hydrogel hybrid conductor (AAHC) with stretchable, adhesive and anti-bacteria properties by in situ formation of a hydrogel network in the aerogel-silver nanowires (AgNWs) assembly. The AgNWs with good conductivity are well-integrated on the inner-surface of shape-memory chitosan aerogel, which created a conductive framework to allow hydrogel back-filling. Reinforcement by the aerogel-silver makes the hybrid hydrogel tough and stretchable. Functional groups from the hydrogel allow strong adhesion to wet tissues through molecular stitches. The inherent bacteria-killing ability of silver ions endows the conductive hydrogel with excellent anti-bacteria performance. The proposed facile strategy of aerogel-assisted assembly of metal nanomaterials with hydrogel opens a new route to incorporate functional nanoscale building blocks into hydrogels.

Compared with raw rectorite microplatelets (RMs), rectorite nanosheets (RNs) have considerably greater application prospects in the preparation of advanced composite materials because of their larger aspect ratio, higher surface reactivity, and intrinsically superior mechanical and physical properties. However, the difficulty in the efficient preparation of RNs significantly limits their large-scale applications. Here, a scalable poly(vinylpyrrolidone)-assisted stirring approach is developed to prepare ultrathin RNs from the abundant natural RMs. A higher production rate (≈0.675 g h

As a typical p-type semiconductor, tellurium (Te) has been widely studied for the construction of photodetectors. However, only the positive photoconductance of Te-based photodetectors based on the photoconductive effect has been observed in the reported literature. Herein, an unusual but interesting phenomenon, in that tellurium nanowires (NWs) behave with negative photoresponse to positive photoresponse under enlarged optical intensities from the UV to VIS-IR region is reported. According to the experiments and simulations, adsorbed oxygen on the surface of Te NWs plays a significant role in the abnormal photoresponse. The inverse photoconductance can be attributed to the competition between the photoconductive effect and the oxygen desorption effect. Moreover, the influence of the size and layers of Te NWs is also discussed. This inverse photoconductance phenomenon is further explored by introducing the Te-Au heterojunction system. Hot-electron injection at the Te-Au heterojunction interface induces a more obvious tendency to behave with a negative photoresponse. These findings will be beneficial for potential applications of Te-NW-based photodetectors.

Realizing autonomous self-healing and high stretchability of flexible supercapacitors over a wide temperature range remains a big challenge because of simultaneous incorporation of self-healing, stretchable and temperature-tolerant elements into a device as well as unfavorable electrochemical kinetics in harsh conditions. Here, we demonstrate for the first time an autonomous self-healing and intrinsically stretchable supercapacitor that can work at all-climate environments assembled by universally self-healing and highly stretchable organohydrogel electrodes with record-high temperature-invariant conductivity of ∼965 S/cm. Benefiting from multiple hydrogen bonding and dynamic metal coordination combined with electrochemistry-favorable components and integrated device configuration, the supercapacitor exhibits outstanding long-term stability, high stretchability, instantaneous and complete capacitive self-healability, and real-time mechanical healing at harsh temperatures from -35 to 80 °C. The superiorities in stretchability, self-healability, and all-climate tolerance enable the supercapacitor presented here as the best performer among the flexible supercapacitors reported to date.

Introducing heating function to oil sorbents opens up a new pathway to the fast cleanup of viscous crude oil spills in situ. The oil sorption speed increases with the rise of the temperature, thus oil sorbents with high heating temperature are desirable. Besides, the oil sorbents also need to be produced environment-friendly. Here we present carbonized melamine-formaldehyde sponges (CMSs) that exhibited superior heating performance and the CMSs could be massively fabricated through a non-polluting pyrolysis process. The conductive CMSs could be heated over 300 °C with a low applied voltage of 6.9 V and keep above 250 °C for 30 min in the air without obvious damage. Such high heating performance enabled heating up the oil spills with a high rate of 2.65 °C·s−1 and 14% improvement of oil sorption coefficient compared with the state-of-the-art value. We demonstrated that one joule-heated CMS could continuously and selectively collect viscous oil spills (9,010 mPa·s) 690 times its own weight in one hour. The CMSs will be a highly competitive sorbent material for the fast remediation of future crude oil spills.

Siloxane rubber shows attractive properties of high stability, elasticity and transparency. Besides, the regulation of its properties renders it widely used in many application fields. However, most of the reported performance improvement methods of siloxane rubber focus on the change of chemical composition of siloxane rubber, including the design of molecular chain and the introduction of other compounds, etc. Such a strategy is still faced with many limitations in practical application. In this work, on the premise of not changing the chemical composition of siloxane rubber, we propose a facile solvothermal polymerization process to change the structure of cross-linking networks, so as to obtain the siloxane rubber with controllable mechanical properties. Compared to the normal curing method, we realized polydimethylsiloxane elastomer (PDMS) with maximum elongation of more than 3,000% (> 10 times of normally cured one) and tensile modulus lower than 0.15 MPa (< 1/10 of normally cured one). In addition to superior stretchability, it gains extra high softness, stickiness and sensitive response to organic solvents. Based on our solvothermal cured PDMS, its applications in oil collection and organic solvent sensor have been demonstrated. It is expected that this method can be readily utilized widely and shows great application potentials.

Nowadays, energy saving and fire protection are non-negligible properties in green buildings. Designing sustainable materials that integrate energy-saving cooling and fire protection performance is...

Suppressing the polysulfide shuttle effect and promoting the conductivity of electrode materials have become efficient ways to achieve high cycling stability for Li–S batteries. However, this still remains a challenge. New multicore closely packed ultrathin-MnO2@N-doped carbon-gear yolk–shell micro-nanostructures are explored as the S host material to trap polysulfides and enhance conductivity. Such composites can accommodate S mass-loading up to 80 wt% via a valid sulfur solution infiltration approach. The cooperation of ultrathin-MnO2 yolks with N-doped carbon internal gear shells can well suppress the polysulfide shuttle effect by strong chemical interactions and physical confinement as well as enhanced conductivity for excellent Li–S battery properties, which enable an initial gravimetric capacity of 1245 mA h g−1 and a low decay rate of 0.03% per cycle over 1000 cycles at 1C. In particular, the composite delivers an initial gravimetric capacity of 1097.8 mA h g−1 and volumetric capacity of 1059.6 mA h cm−3 at 2C rate. Specifically, the electrochemical performance of the designed composite at different electrolyte/S ratios is firstly investigated in this study, and is a promising approach with the high-performance cathode material for Li–S batteries.

Undoubtedly humidity is a non-negligible and sensitive problem for cellulose, which is usually regarded as one disadvantage to cellulose-based materials because of the uncontrolled deformation and mechanical decline. But the lack of an in-depth understanding of the interfacial behavior of nanocellulose in particular makes it challenging to maintain anticipated performance for cellulose-based materials under varied relative humidity (RH). Starting from multiscale mechanics, we herein carry out first-principles calculations and large-scale molecular dynamics simulations to demonstrate the humidity-mediated interface in hierarchical cellulose nanocrystals (CNCs) and associated deformation modes. More intriguingly, the simulations and subsequent experiments reveal that water molecules (moisture) as the interfacial media can strengthen and toughen nanocellulose simultaneously within a suitable range of RH. From the perspective of interfacial design in materials, the anomalous mechanical behavior of nanocellulose with humidity-mediated interfaces indicates that flexible hydrogen bonds (HBs) play a pivotal role in the interfacial sliding. The difference between CNC-CNC HBs and CNC-water-CNC HBs triggers the humidity-mediated interfacial slipping in nanocellulose, resulting in the arising of a pronounced strain hardening stage and the suppression of strain localization during uniaxial tension. This inelastic deformation of nanocellulose with humidity-mediated interfaces is similar to the Velcro-like behavior of a wet wood cell wall. Our investigations give evidence that the humidity-mediated interface can promote the mechanical enhancement of nanocellulose, which would provide a promising strategy for the bottom-up design of cellulose-based materials with tailored mechanical properties.

Lightweight yet strong paper with high toughness is desirable especially for impact protection. Herein we demonstrated electrically conductive and mechanically robust paper (AP/PB-GP) made of reduced graphene oxide via interfacial crosslinking with 1-aminopyrene (AP) and 1-pyrenebutyrat (PB) small molecules. The AP/PB-GP with thickness of over ten micrometer delivers a record-high toughness (∼69.67 ± 15.3 MJ m−3 in average), simultaneously with superior strength (close to 1 GPa), allowing an impressive specific penetration energy absorption (∼0.17 MJ kg−1) at high impact velocities when used for ballistic impact protection. Detailed interfacial and structural analysis reveals that the reinforcement is synergistically determined by π-π interaction and H-bonding linkage between adjacent graphene lamellae. Especially, the defective pores within the graphene platelets benefit the favorable adsorption of the pyrene-containing molecules, which imperatively maximizes the interfacial binding, facilitating deflecting crack and plastic deformation under loading. Density functional theory simulation suggests that the coupling between the polar functional groups, e.g., −COOH, at the edges of graphene platelets and −NH2 and −COOH of AP/PB are critical to the formation of hydrogen bonding network.

Magnesium calcite (Mg-calcite) mesocrystal is widespread in the biominerals with specific functions. Until now, it remains challenging to obtain Mg-calcite mesocrystals without organic additives and the formation mechanism of Mg-calcite mesocrystals in the ocean is not clear yet. We report here the synthesis of corn-like Mg-calcite mesocrystals from pure amorphous calcium carbonate (ACC) via a facile method only by using Ca2+ and Mg2+. The obtained Mg-calcite is composed of many nanocubes with common crystallographic orientation, which shows very good single crystal feature. In the crystallizing procedure, the ACC nanospheres rapidly agglomerate into Mg-calcite corn-like mesocrystal by oriented attachment (OA) in a certain direction, which belongs to the non-classical nucleation. By this method, the molar ratio of Ca2+ and Mg2+ plays a vital role in the whole crystallization procedure, which may shed a new light on disclosing the mechanism behind for the effect of seawater in the formation of biological Mg-calcite in nature.

Interfacial solar steam generation (ISSG) utilizing local heating technology for evaporation at the water-to-steam interface is drawing great attention because of its high efficiency of solar-thermal conversion for a sustainable and eco-friendly drinking water regeneration process. Here, inspired by the structure of penguin feathers and polar bear hairs that both have macropores to trap air for thermal insulation, we report a bionic solar evaporator (BSE) with macroporous skeleton for partial thermal management and macro patulous channels for abundant water transportation and rapid steam extraction. Meanwhile, the 3D hierarchical isotropic truss structures can induce multiple light reflections to enable omnidirectional light absorption, and bimodal pores facilitate ion diffusion to suppress salt deposits. This BSE exhibits an evaporation rate of 2.3 kg m

Summary Plastics play a critical role in daily life but possess a considerably increasing negative impact on the environment and human health. Fabrication of biodegradable and eco-friendly alternatives with competitive properties for plastic substitute is urgently needed. Here, inspired by the hierarchical structure of nacre, we firstly developed a high-performance nacre-inspired composite with high transmittance (83.4% at 550 nm) and high haze (88.8% at 550 nm) via an aerosol-assisted biosynthesis process combined with the hot-press technique. The nacre-inspired composite film combines higher strength (482 MPa) and toughness (17.71 MJ m−3) than most other nacre-inspired films, and can be folded into various shapes without visible failure after unfolding. Moreover, compared with most commercial plastic films, it exhibits a lower thermal expansion coefficient (∼3 ppm K−1) and higher maximum service temperature besides better mechanical properties, which makes it a promising alternative to plastics in many technical fields.

Although nickel-based catalysts display good catalytic capability and excellent corrosion resistance under alkaline electrolytes for water splitting, it is still imperative to enhance their activity for real device applications. Herein, we decorated Ni0.85Se hollow nanospheres onto reduced graphene oxide (RGO) through a hydrothermal route, then annealed this composite at different temperatures (400 °C, NiSe2-400 and 450 °C, NiSe2-450) under argon atmosphere, yielding a kind of NiSe2/RGO composite catalysts. Positron annihilation spectra revealed two types of vacancies formed in this composite catalyst. We found that the NiSe2-400 catalyst with dual Ni-Se vacancies is able to catalyze the oxygen evolution reaction (OER) efficiently, needing a mere 241 mV overpotential at 10 mA·cm−2. In addition, this catalyst exhibits outstanding stability. Computational studies show favorable energy barrier on NiSe2-400, enabling moderate OH− adsorption and O2 desorption, which leads to the enhanced energetics for OER.

Printable elastic conductors promote the wide application of consumable electronic textiles (e-textiles) for pervasive healthcare monitoring and wearable computation. To assure a clean appearance, the e-textiles require a washing process to clean up the dirt after daily use. Thus, it is crucial to develop low-cost printable elastic conductors with strong adhesion to the textiles. Here, we report a composite elastic conductor based on Ag nanowires (NWs) and polyurethane elastomer. The composite could be dispersed into ink and easily printed onto textiles. One-step print could form robust conductive coatings without sealing on the textiles. Interestingly, the regional concentration of Ag NWs within the polyurethane matrix was observed during phase inversion, endowing the elastic conductor with a low percolation threshold of 0.12 vol.% and high conductivity of 3,668 S·cm−1. Thanks to the high adhesion of the elastic conductors, the resulted e-textiles could withstand repeated stretching, folding, and machine washing (20 times) without obvious performance decay, which reveals its potential application in consumable e-textiles.

The high surface energy of nanomaterials endows them a metastable nature, which greatly limits their application. However, in some cases, the degradation process derived from the poor stability of nanomaterials offers an unconventional approach to design and obtain functional nanomaterials. Herein, based on the poor stability of ZnSe-[DETA]0.5 hybrid nanobelts, we developed a new strategy to chemically graphitize and functionalize graphene oxide (GO). When ZnSe[DETA]0.5 hybrid nanobelts encountered a strong acid, they were attacked by H+ cations and could release highly reactive Se2− anions into the reaction solution. Like other common reductants (such as N2H4·H2O), these Se2− anions exhibited an excellent ability to restore the structure of GO. The structural restoration of GO was greatly affected by the reaction time, the volume of HCl, and the mass ratio between GO and ZnSe[DETA]0.5 nanobelts. By carefully controlling the reaction process and the post-processing process, we finally obtained several Se-based reduced GO (RGO) nanocomposites (such as ZnSe/Se-RGO, ZnSe-RGO, and Se-RGO) and various selenide/metal-RGO nanocomposites (such as Ag2Se-RGO, Cu2Se-RGO, and Pt-RGO). Although the original structure and composition of ZnSe[DETA]0.5 nanobelts are destroyed, the procedure presents an unconventional way to chemically graphitize and functionalize GO and thus provides a new material synthesis platform for nanocomposites.

Summary Batch hydrothermal reactor is known as a closed system, and what happens in this “black box” is mysterious. Now, by using the tendency of graphene oxide (GO) to align along the flow and the fixation effect of thermoset resin, the hydrothermal annular convection can be inferred from the axisymmetric poloidal structure and GO-assembled annular distribution. Temperature difference and geometric symmetricity of the reactor account for the annular convection, which is also found to be affected by solution viscosity and reactor parameters. Numerical simulations reproduce the annular convection and are used to investigate the parameter space beyond experiments. Plume flows occur at the bottom of the reactor due to flow instability. Irregular and intensive flow is against the synthesis of high-aspect-ratio nanomaterials and monolithic gels. It is noteworthy that large-scale batch hydrothermal synthesis may not be feasible for some nanowires, nanosheets, and particularly gels due to the non-negligible flow influence.

Solar steam generation is an emerging research field to approach the challenge of water shortages all around the world. Abundant light absorber materials have been developed to improve the broadban...

Photoelectrochemical (PEC) hydrogen production is of great interest as an ideal avenue towards clean and renewable energy. However, the instability and low energy conversion efficiency of photoanodes hinder their practical applications. Here we address these issues by introducing a hole extraction layer (HEL) which could rapidly transfer and consume photogenerated holes. The HEL is constructed by reduced graphene oxide (RGO) and other cocatalysts that enable rapid transfer and subsequent consumption of holes, respectively. Specifically, we showcase a high-stability photoanode composed of CdSeTe nanowires (CST NWs) and RGO/PdS nanoparticles (PdS NPs) based HEL. The photoanode achieves excellent photocorrosion resistance, which allows stable hydrogen evolution for > 2 h at 0.5 VRHE.

Owing to the stimulus-responsive and dynamic properties, magnetism-driven assembly of building blocks to form ordered structures is always a marvelous topic. While abundant magnetic assemblies have been developed in ideal physical and chemical conditions, it remains a challenge to realize magnetic assembly in complicated biological systems. Herein, we report a kind of biomacromolecule-modified magnetic nanosheets, which are mainly composed of superparamagnetic graphene oxide (γ-Fe2O3@GO), the tumor-targeting protein transferrin (TF), and the mitochondrion-targeting peptide (MitP). Such large-size nanosheets (0.5–1 μm), noted as L-Fe2O3@GO-MitP-TF, can successfully in situ assemble on the surface of tumor cells in a size-dependent and tumor cell-specific way, leading to severe inhibition of nutrient uptake for the tumor cells. More significantly, the nanostructures could efficiently confine the tumor cells, preventing both invasion and metastasis of tumor cells both in vitro and in vivo. Moreover, the 2D assemblies could remarkably disrupt the mitochondria and induce apoptosis, remarkably eradicating tumors under near-infrared (NIR) irradiation. This study sheds light on the development of new nano-systems for efficient cancer therapy and other biomedical applications.

Developing efficient charge separation strategies is essential to achieve high-power conversion efficiency in the fields of chemistry, biology, and material science. Herein, we develop a facile strategy for fabrication of unique wafer-scale radial nanowire assemblies by exploiting shear force in rotary solution. The assembly mechanism can be well revealed by the large-scale stochastic dynamics simulation. Free electrons can be rapidly generated to produce quantitatively tunable current output when the radial nanowire assemblies rotate under the magnetic field. Moreover, the photoconductive performance of the radial semiconductor nanowire assemblies can be remarkably enhanced as the electron-hole recombination was retrained by the efficient charge separation under the rotating magnetic field. Such large-scale unique nanowire assemblies will facilitate the design of an efficient charge separation process in biosystem, sensors, and photocatalysis.

Chirality-the property of an object wherein it is distinguishable from its mirror image-is of widespread interest in chemistry and biology1-6. Regioselective magnetization of one-dimensional semiconductors enables anisotropic magnetism at room temperature, as well as the manipulation of spin polarization-the properties essential for spintronics and quantum computing technology7. To enable oriented magneto-optical functionalities, the growth of magnetic units has to be achieved at targeted locations on a parent nanorod. However, this challenge is yet to be addressed in the case of materials with a large lattice mismatch. Here, we report the regioselective magnetization of nanorods independent of lattice mismatch via buffer intermediate catalytic layers that modify interfacial energetics and promote regioselective growth of otherwise incompatible materials. Using this strategy, we combine materials with distinct lattices, chemical compositions and magnetic properties, that is, a magnetic component (Fe3O4) and a series of semiconducting nanorods absorbing across the ultraviolet and visible spectrum at specific locations. The resulting heteronanorods exhibit optical activity as induced by the location-specific magnetic field. The regioselective magnetization strategy presented here enables a path to designing optically active nanomaterials for chirality and spintronics.

Efficient initiation and resolution of inflammation are crucial for wound repair. However, with using tissue adhesives for wound repair, patients occasionally suffered from delayed healing process because slow elimination of those exogenous adhesives generally leads to chronic inflammation. As the demand for minimal invasive therapy continues to rise, desire for adhesive materials that can effectively reconnect surgical gaps and promote wound regeneration becomes increasingly urgent. Herein, by exploiting the inherent porous structure and performance of adhesion to tissue of mesoporous silica nanoparticles (MSNs), we demonstrate a tissue adhesive that can elicit acute inflammatory response and get eliminated after tissue reformation. With formation of nanocomposites in wound gaps, the injured tissues can get reconnected conveniently. The resultant accelerated healing process verify that the strategy of exploiting unique properties of nanomaterials can effectively promote inflammation resolution and wound repair. This design strategy will inspire more innovative tissue adhesives for clinical applications.

Due to their unique structure, one dimensional (1D) nanomaterials have attracted considerable attention and shown potential applications in modern nano-devices. With advances in chemistry and materials science, integrating these 1D nanoscale-building blocks for macroscopic well-designed assemblies will provide new opportunities for sustainable and advanced applications. This article comprehensively reviews the structure–property relationship of assembled nanowire materials compared with the disordered NW statement. Specifically, we firstly highlight the anisotropy phenomenon of 1D assemblies, including the anisotropic conductive properties, optical properties, thermal conduction properties, and anisotropic strain sensing. Next, we systematically review the superior properties of ordered 1D assembly devices compared to random samples to elucidate the advantages of well-defined structures. The programmability of ordered assemblies with predictable architectures for large-scale devices is also briefly commented on. Finally, a summary and perspectives on challenges and future opportunities are presented.

Electrochemical reduction of carbon dioxide (CO2) to value-added chemicals and fuels offers a potential platform to store renewable energy in chemical bonds and thus a route to carbon recycling. Due to its high efficiency and reasonable economic feasibility, the conversion of CO2 to carbon monoxide (CO) is considered as the most promising candidate reaction in the industrial market. Recently, the understanding of the basic mechanism of CO2 reduction to CO has become clearer, which has also motivated the design principles for better-performing catalysts including morphology, size, grain boundary, and surface engineering. Various catalysts (noble and non-noble metals, transition metal chalcogenides, carbon materials, and molecular catalysts) have been developed to efficiently catalyze the CO2-to-CO conversion. Here we survey recent key progress in CO2-to-CO conversion in the field of electrocatalytic CO2 reduction. We will highlight the principles of designing electrocatalysts for the selective formation of CO, the influence of electrolytes on the selectivity and conversion rate, and the emerging applications of electrolyzers for large-scale CO production. We finally provide an outlook on several development opportunities that could lead to new advancements in this promising research field.