Metal–organic frameworks (MOFs), which consist of central metal nodes and organic linkers, constitute a fast growing class of crystalline porous materials with excellent application potential. Herein, a series of Mn‐based multimetallic MOF (bimetallic and trimetallic MIL‐100) nano‐octahedra are prepared by a facile one‐pot synthetic strategy. The types and proportions of the incorporated elements can be tuned while retaining the original topological structure. The introduction of other metal ions is verified at the atomic level by combining X‐ray absorption fine structure experiments and theoretical calculations. Furthermore, these multimetallic Mn‐based MIL‐100 nano‐octahedra are utilized as sulfur hosts to prepare cathodes for Li–S batteries. The MnNi‐MIL‐100@S cathode exhibits the best Li–S battery performance among all reported MIL‐100@S composite cathode materials, with a reversible capacity of ≈708.8 mAh g−1 after 200 cycles. The synthetic strategy described herein is utilized to incorporate metal ions into the MOF architecture, of which the parent monometallic MOF nano‐octahedra cannot be prepared directly, thus rationally generating novel multimetallic MOFs. Importantly, the strategy also allows for the general synthesis and study of various micro‐/nanoscale MOFs in the energy storage field.

While stretchable micro‐supercapacitors (MSCs) have been realized, they have suffered from limited areal electrochemical performance, thus greatly restricting their practical electronic application. Herein, a facile strategy of 3D printing and unidirectional freezing of a pseudoplastic nanocomposite gel composed of Ti3C2Tx MXene nanosheets, manganese dioxide nanowire, silver nanowires, and fullerene to construct intrinsically stretchable MSCs with thick and honeycomb‐like porous interdigitated electrodes is introduced. The unique architecture utilizes thick electrodes and a 3D porous conductive scaffold in conjunction with interacting material properties to achieve higher loading of active materials, larger interfacial area, and faster ion transport for significantly improved areal energy and power density. Moreover, the oriented cellular scaffold with fullerene‐induced slippage cell wall structure prompts the printed electrode to withstand large deformations without breaking or exhibiting obvious performance degradation. When imbued with a polymer gel electrolyte, the 3D‐printed MSC achieves an unprecedented areal capacitance of 216.2 mF cm−2 at a scan rate of 10 mV s−1, and remains stable when stretched up to 50% and after 1000 stretch/release cycles. This intrinsically stretchable MSC also exhibits high rate capability and outstanding areal energy density of 19.2 µWh cm−2 and power density of 58.3 mW cm−2, outperforming all reported stretchable MSCs.

No abstract

A solar-thermal water evaporation structure that can continuously generate clean water with high efficiency and good salt rejection ability under sunlight is highly desirable for water desalination, but its realization remains challenging. Here, a hierarchical solar-absorbing architecture is designed and fabricated, which comprises a 3D MXene microporous skeleton with vertically aligned MXene nanosheets, decorated with vertical arrays of metalorganic framework-derived 2D carbon nanoplates embedded with cobalt nano particles. The rational integration of three categories of photothermal materials enables broadband light absorption, efficient light to heat conversion, low heat loss, rapid water transportation behavior, and much-improved corrosion and oxidation resistance. Moreover, when assembling with a hydrophobic insulating layer with hydrophilic channel, the MXene-based solar absorber can exhibit effective inhibition of salt crystallization due to the ability to advect and diffuse concentrated salt back into the water. As a result, when irradiating under one sun, the solar-vapor conversion efficiency of the MXene-based hierarchical design can achieve up to ≈93.4%, and can remain over 91% over 100 h to generate clean vapor for stable and continuous water desalination. This strategy opens an avenue for the development of MXenebased solar absorbers for sustainable solar-driven desalination.

The fabrication of fully printable, flexible micro‐supercapacitors (MSCs) with high energy and power density remains a significant technological hurdle. To overcome this grand challenge, the 2D material MXene has garnered significant attention for its application, among others, as a printable electrode material for high performing electrochemical energy storage devices. Herein, a facile and in situ process is proposed to homogeneously anchor hydrous ruthenium oxide (RuO2) nanoparticles on Ti3C2Tx MXene nanosheets. The resulting RuO2@MXene nanosheets can associate with silver nanowires (AgNWs) to serve as a printable electrode with micrometer‐scale resolution for high performing, fully printed MSCs. In this printed nanocomposite electrode, the RuO2 nanoparticles contribute high pseudocapacitance while preventing the MXene nanosheets from restacking, ensuring an effective ion highway for electrolyte ions. The AgNWs coordinate with the RuO2@MXene to guarantee the rheological property of the electrode ink, and provide a highly conductive network architecture for rapid charge transport. As a result, MSCs printed from the nanocomposite inks demonstrate volumetric capacitances of 864.2 F cm−3 at 1 mV s−1, long‐term cycling performance (90% retention after 10 000 cycles), good rate capability (304.0 F cm−3 at 2000 mV s−1), outstanding flexibility, remarkable energy (13.5 mWh cm−3) and power density (48.5 W cm−3).

The rapid progression of portable and wearable electronics has necessitated the development of high‐performing, miniaturized energy‐storage devices with flexible form factors and high energy and power delivery. Printed micro‐supercapacitors (MSCs), with in‐plane interdigital configurations, is touted as a promising choice to fulfill these requirements. New printing technologies can assemble MSCs with fiscal and environmental benefits, large form factors, and at high throughputs, qualities not afforded with conventional microfabrication technologies. Here, recent progress in the preparation of functional ink systems for wearable MSCs, encompassing electrode materials, conductor materials, and electrolytes, is presented. First, a comprehensive background of the fundamentals of printing technology is introduced, with discussions focusing on methods of improving ink functionality while simultaneously retaining good printability. Second, various printing techniques to ensure manufacturable scaling of wearable MSCs with high areal electrochemical performance and small footprint are explored. Within the scope of these two topics, various issues that hinder the full materialization of widespread adoption of printed MSC and next steps to overcome these issues are discussed. Further deep dives in scientific and technical challenges are also presented, including limited functionality of the inks, low printing resolution, overlay accuracy, and complex encapsulation.

Skin-mountable physical sensors that can individually detect mechanical deformations with high strain sensitivity within a broad working strain range and temperature variations with accurate temperature resolution are a sought-after technology. Herein, a stretchable temperature and strain dual-parameter sensor that can precisely detect and distinguish strain from temperature stimuli without crosstalk is developed, based on a printable titanium carbide (MXene)-silver nanowire (AgNW)-PEDOT:PSStellurium nanowire (TeNW) nanocomposite. With this dualparameter sensor, strain and temperature are effectively transduced into electrically isolated signals through the electrically conductive MXene-AgNW and thermoelectric PEDOT:PSS-TeNW components, respectively. In addition, the synergistic effect between the MXene nanosheets and PEDOT:PSS also greatly enhances the stretchability and sensitivity of the sensing devices. These properties enable the nanocomposite to decouple responses between temperature and strain stimuli with an accurate temperature resolution of 0.2 °C and a gauge factor of up to 1933.3 in a working strain range broader than 60%.

cell design have presented numerous safety hazards and economic challenges, [3][4][5] which make LIBs less suitable for largescale applications. Compared with organic LIBs, aqueous rechargeable Zn-ion batteries (ZIBs) equipped with nonflammable and highly ion conductive aqueous electrolytes are highly desirable. They benefit from a high theoretical capacity (a gravimetric capacity of 820 mAh g −1 and a volumetric capacity of 5855 mAh cm −3 ) and a low plating/stripping potential (−0.76 V vs standard hydrogen electrode), as well as a high natural abundance of metallic Zn. [6][7][8] Unfortunately, the uncontrolled formation of dendrites, undesired side reactions (e.g., corrosion, hydrogen evolution, and by-product formation), and huge volume variation during repeated Zn deposition-dissolution processes of the host-less metallic Zn anode not only limit the efficiency of plating and stripping, but also result in a remarkably short lifespan, or even internal short-circuiting. [9][10][11] In order to address the issues mentioned above, several strategies have been proposed to regulate the Zn plating/stripping behaviors for stable Zn metal batteries, including surface modification, [12][13][14] electrolyte optimization, [15][16][17] and electrode structural design. [18][19][20] For instance, an ultrathin MXene layer and glucose have been used as an artificial layer and a multifunctional electrolyte additive to stabilize Zn metal anodes, Aqueous Zn metal batteries have attracted much attention due to their high intrinsic capacity, high safety, and low cost. Nevertheless, uncontrollable dendrite growth and adverse side reactions of Zn anodes seriously hinder their further application. Herein, a three-dimensional (3D) porous graphene-carbon nanotubes scaffold decorated with metal-organic framework derived ZnO/C nanoparticles (3D-ZGC) is fabricated as the host for dendrite-free Zn-metal composite anodes. The zincophilic ZnO/C nanoparticles act as preferred deposition sites with low nucleation barriers to induce homogeneous Zn deposition. The mechanically robust 3D scaffold with high conductivity not only suppresses the formation of dendritic Zn by reducing the local current density and homogenizing Zn 2+ ion flux, but also inhibits volume changes during the long-term plating/stripping process. As a result, the 3D-ZGC composite anodes afford unprecedented Zn plating-stripping stability at an ultrahigh current density of 20 mA cm -2 for 1500 cycles with low overpotential (<65 mV) when used in a symmetric cell. When coupled with MnO 2 cathodes, the assembled Zn@3D-ZGC//MnO 2 full batteries deliver an enhanced cycling stability for up to 6000 cycles at 2000 mA g -1 , demonstrating the potential of the 3D-ZGC composite anode for advanced Zn metal batteries.