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Simultaneously adding multiple drugs and other chemical reagents to individual droplets at specific time points presents a significant challenge, particularly when dealing with tiny droplets in high-throughput screening applications. In this study, a micropatterned polymer chip is developed as a miniaturized platform for light-induced programmable drug addition in cell-based screening. This chip incorporates a porous superhydrophobic polymer film with atom transfer radical polymerization reactivity, facilitating the efficient grafting of azobenzene methacrylate, a photoconformationally changeable group, onto the hydrophilic regions of polymer matrix at targeted locations and with precise densities. By employing light irradiation, the cyclodextrin-azobenzene host-guest complexes formed on the polymer chip can switch from an "associated" to a "dissociated" state, granting precise photochemical control over the supramolecular coding system and its surface patterning ability. Significantly, the exceptional spatial and temporal control offered by these chemical transitions empowers to utilize digital light processing systems for simultaneous regulation and release of cyclodextrin-bearing drugs across numerous droplets containing suspended or adhered cells. This approach minimizes mechanical disruption while achieving precise control over the timing of addition, dosage, and integration varieties of released drugs in high-throughput screening, all programmable to meet specific requirements., (© 2023 Wiley-VCH GmbH.)

Concave nanostructure with highly branched architecture and abundant step atoms is one kind of desirable materials for energy conversion devices. However, current synthetic strategies for non-noble metal-based NiCoP concave nanostructure still remain challenging. Herein, we demonstrate a site-selective chemical etching and subsequent phosphorating strategy to fabricate highly branched NiCoP concave nanocrosses (HB-NiCoP CNCs). The HB-NiCoP CNCs are consisted of six axial arms in three-dimensional space and each protruding arm is equipped with high-density atomic steps, ledges and kinks. As an electrocatalyst towards oxygen evolution reaction, the HB-NiCoP CNCs exhibit remarkably enhanced activity and stability, with small overpotential of 289 mV to reach 10 mA cm -2 , surpassing the NiCoP nanocages and commercial RuO 2 . The superior OER performance of HB-NiCoP CNCs is originated from the highly branched concave structure, the synergistic effect between bimetal Ni and Co atoms, as well as the electronic structure modulation from P., (© 2023 Wiley-VCH GmbH.)

Most existing stretchable batteries can generally only be stretched uniaxially and suffer from poor mechanical and electrochemical robustness to withstand extreme mechanical and environmental challenges. A highly efficient bifunctional electrocatalyst is herein developed via the unique self-templated conversion of a guanosine-based supramolecular hydrogel and presents a fully integrated design strategy to successfully fabricate an omnidirectionally stretchable and extremely environment-adaptable Zn-air battery (ZAB) through the synergistic engineering of active materials and device architecture. The electrocatalyst demonstrates a very low reversible overpotential of only 0.68 V for oxygen reduction/evolution reactions (ORR/OER). This ZAB exhibits superior omnidirectional stretchability with a full-cell areal strain of >1000% and excellent durability, withstanding more than 10 000 stretching cycles. Promisingly, without any additional pre-treatment, the ZAB exhibits outstanding ultra-low temperature tolerance (down to -60 °C) and superior waterproofness, withstanding continuous water rinsing (>5 h) and immersion (>3 h). The present work offers a promising strategy for the design of omnidirectionally stretchable and high-performance energy storage devices for future on-skin wearable applications., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

The temporal and spatial control of natural systems has aroused great interest for the creation of synthetic mimics. By using boronic ester based dynamic covalent chemistry and coupling it with an internal pH feedback system, we have developed a new chemically fueled reaction network for non-equilibrium supramolecular chiral G-quadruplex hydrogels with programmable lifetimes from minutes, to hours, to days, as well as high transparency and conductivity, excellent injectability, and rapid self-healing properties. The system can be controlled by the kinetically controlled in situ formation and dissociation of dynamic boronic ester bonds between the cis-diol of guanosine (G) and 5-fluorobenzoxaborole (B) in the presence of chemical fuels (KOH and 1,3-propanesultone), thereby leading to a precipitate-solution-gel-precipitate cycle under non-equilibrium conditions. A combined experimental-computational approach showed the underlying mechanism of the non-equilibrium self-assembly involves aggregation and disaggregation of right-handed helical G-quadruplex superstructures. The proposed dynamic boronic ester-based non-equilibrium self-assembly strategy offers a new option to design next-generation adaptive and interactive smart materials., (© 2021 Wiley-VCH GmbH.)

Silver nanoparticles (AgNPs) are in situ synthesized for the first time on microfibrillated silk (MFS) exfoliated from domesticated Philosamia cynthia ricini (eri) and Bombyx mori (mulberry) silkworm silk fibers. The process is rapid (hours time), does not rely on harmful chemicals, and produces robust and flexible AgNPs coated MFS (MFS-AgNPs) protein papers with excellent handling properties. None of these can be achieved by approaches used in the past to fabricate AgNPs silk systems. MFS bonds the AgNPs strongly, providing good support and stabilization for the NPs, leading to strong wash fastness. The mechanical properties of the MFS-AgNPs papers largely do not change compared to the MFS papers without nanoparticles, except for some higher concentration of AgNPs in the case of mulberry silk. The improved tensile properties of eri silk papers with or without AgNPs compared to mulberry silk papers can be attributed to the higher degree of fibrillation achieved in eri silk and its inherent higher ductility. MFS-AgNPs from eri silk also exhibit strong antibacterial activity. This study provides the basis for the development of smart protein papers based on silk fiber and functional nanomaterials., (© 2020 Wiley-VCH GmbH.)

Organic electrode materials are promising for green and sustainable lithium-ion batteries. However, the high solubility of organic materials in the liquid electrolyte results in the shuttle reaction and fast capacity decay. Herein, azo compounds are firstly applied in all-solid-state lithium batteries (ASSLB) to suppress the dissolution challenge. Due to the high compatibility of azobenzene (AB) based compounds to Li 3 PS 4 (LPS) solid electrolyte, the LPS solid electrolyte is used to prevent the dissolution and shuttle reaction of AB. To maintain the low interface resistance during the large volume change upon cycling, a carboxylate group is added into AB to provide 4-(phenylazo) benzoic acid lithium salt (PBALS), which could bond with LPS solid electrolyte via the ionic bonding between oxygen in PBALS and lithium ion in LPS. The ionic bonding between the active material and solid electrolyte stabilizes the contact interface and enables the stable cycle life of PBALS in ASSLB., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Organic compounds are desirable alternatives for sustainable lithium-ion battery electrodes. However, the electrochemical properties of state-of-the-art organic electrodes are still worse than commercial inorganic counterparts. Here, a new chemistry is reported based on the electrochemical conversion of nitro compounds to azo compounds for high performance lithium-ion batteries. 4-Nitrobenzoic acid lithium salt (NBALS) is selected as a model nitro compound to systemically investigate the structure, lithiation/delithiation mechanism, and electrochemical performance of nitro compounds. NBALS delivers an initial capacity of 153 mAh g -1 at 0.5 C and retains a capacity of 131 mAh g -1 after 100 cycles. Detailed characterizations demonstrate that during initial electrochemical lithiation, the nitro group in crystalline NBALS is irreversibly reduced into an amorphous azo compound. Subsequently, the azo compound is reversibly lithiated/delithiated in the following charge/discharge cycles with high electrochemical performance. The lithiation/delithiation mechanism of azo compounds is also validated by directly using azo compounds as electrode materials, which exhibit similar electrochemical performance to nitro compounds, while having a much higher initial Coulombic efficiency. Therefore, this work proves that nitro compounds can be electrochemically converted to azo compounds for high performance lithium-ion batteries., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)