Segregated PLLA/MWCNTs nanocomposites were synthesized with high-performance EMI shielding.

Ligand exchange can enhance the rate of electron injection which plays an important role in photoresponse.

Lithium–sulfur (Li–S) batteries are promising energy‐storage devices because of their high theoretical energy densities. However, the practical application of Li–S batteries is still impeded by the poor cycling performance and rate capability at practical conditions. In order to improve the performance of practical Li–S batteries, a hierarchical Mo2C nanocluster/carbon nanosheets hybrid based hollow spherical material (Mo2C/CHS) is designed and prepared. The hollow spheres composed of stacked carbon nanosheets can facilitate the infiltration of electrolyte. The ultrasmall and highly conductive Mo2C nanocrystals are confined in the carbon nanosheets and expose more active sites for anchoring and conversion of lithium polysulfides and increase the number of the nuclei for Li2S2/Li2S precipitation. Benefitting from the synergistic effects, Mo2C/CHS greatly promotes electrochemical kinetics in Li–S batteries with high sulfur loading (5 mg cm−2). Even under lean electrolyte conditions (E/S = 7 μL mgsulfur−1), the Li–S batteries with Mo2C/CHS added exhibit a discharge capacity of 904 mAh g−1 at the high current rate of 0.5 C, and with 894 mAh g−1 maintained after 200 cycles. This work provides a fundamental understanding of the electrochemical processes and guides the rational design of host and additive materials for practical Li–S batteries.

Grippers are widely used for the gripping, manipulation, and assembly of objects with a wide range of scales, shapes, and quantities in research, industry, and our daily lives. A simple yet universal solution is very challenging. Here, we manage to address this challenge utilizing a simple shape memory polymer (SMP) block. The embedding of objects into the SMP enables the gripping while the shape recovery upon stimulation facilitates the releasing. Systematic studies show that friction, suction, and interlocking effects dominate the grip force individually or collectively. This universal SMP gripper design provides a versatile solution to grip and manipulate multiscaled (from centimeter scale down to 10-μm scale) 3D objects with arbitrary shapes, in individual, deterministic, or massive, selective ways. These extraordinary capabilities are demonstrated by the gripping and manipulation of macroscaled objects, mesoscaled steel sphere arrays and microparticles, and the selective and patterned transfer printing of micro light-emitting diodes.

Transfer printing that enables heterogeneous integration of materials in desired layouts offers unprecedented opportunities for developing high-performance unconventional electronic systems. However, large-area integration of ultrathin and delicate functional micro-objects with high yields in a programmable fashion still remains as a great challenge. Here, we present a simple, cost-effective, yet robust transfer printing technique via a shape-conformal stamp with actively actuated surface microstructures for programmable and scalable transfer printing with high reliability and efficiency. The shape-conformal stamp features the polymeric backing and commercially available adhesive layer with embedded expandable microspheres. Upon external thermal stimuli, the embedded microspheres expand to form surface microstructures and yield weak adhesion for reliable release. Systematic experimental and computational studies reveal the fundamental aspects of the extraordinary adhesion switchability of stamp. Demonstrations of this protocol in deterministic assemblies of diverse challenging inorganic micro-objects illustrate its extraordinary capabilities in transfer printing for developing high-performance flexible inorganic electronics.

High-performance all-inorganic perovskite-based metal/semiconductor/metal (MSM) photodetectors with a bilayer composite film of mesoporous TiO and CsPbBr quantum dots as a photosensitizer were prepared. The photodetectors demonstrated significantly improved on/off ratios of nearly three orders of magnitude compared to those of pure bromine-based perovskite nanocrystal photodetectors with an MSM structure.

Transfer printing, as an important assembly technique, has attracted much attention due to its valuable merits to develop novel forms of electronics such as stretchable inorganic electronics requiring the heterogeneous integration of inorganic materials with soft elastomers. Here, we report on a laser-driven programmable non-contact transfer printing technique via a simple yet robust design of active elastomeric microstructured stamp that features cavities filled with air and embedded under the contacting surface, a micro-patterned surface membrane that encapsulates the air cavities and a metal layer on the inner-cavity surfaces serving as the laser-absorbing layer. The micro-patterned surface membrane can be inflated dynamically to control the interfacial adhesion, which can be switched from strong state to weak state by more than three orders of magnitude by local laser heating of the air in the cavity with a temperature increase below 100°C. Theoretical and experimental studies reveal the fundamental aspects of the design and fabrication of the active elastomeric microstructured stamp and the operation of non-contact transfer printing. Demonstrations in the programmable transfer printing of micro-scale silicon platelets and micro-scale LED chips onto various challenging receivers illustrate the extraordinary capabilities for deterministic assembly that are difficult to address by existing printing schemes, thereby creating engineering opportunities in areas requiring the heterogeneous integration of diverse materials such as curvilinear electronics and MicroLED displays.

A novel and direct approach to synthesize 1-aminoindole derivatives by Rh(iii)-catalyzed cyclization of 2-acetyl-1-arylhydrazines with diazo compounds via aryl C-H activation has been developed. This intermolecular annulation involving tandem C-H activation, cyclization and condensation steps proceeds efficiently in water, obviates the need of external oxidants, and displays a broad substituent scope.