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The combination of different elements in alloy catalysts can lead to improved activity as it provides opportunities to tune the electronic structures of surface atoms. However, the synthesis and performance screening of alloy catalysts through a vast chemical space are cost- and labor-intensive. Herein, a UV-induced, high-throughput method is reported for the synthesis and screening of alloy electrocatalysts in a fast and low-cost manner. A platform that integrates 37 mini-reaction-cells enables simultaneous UV-induced photodeposition of alloy nanoparticles with up to 37 compositions. These mini-reaction-cells further allow a transfer-free, high-throughput electrochemical performance screening. Binary (PtPd, PtIr, PdIr), ternary (PtPdIr, PtRuIr) and quaternary (PtPdRuIr) alloys have been synthesized with the activity of the binary alloys (57 compositions) for hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) being screened. The predicted high performance of identified alloy compositions are subsequently validated by standard measurements using a rotating disk electrode configuration. It is found that the as-synthesized alloy nanoparticles are rich in twin boundaries and thus possess lattice strain. Density functional theory calculation implies that the high ORR activity of the screened Pt_0.75Pd_0.25 alloy originates from the interplay between the differentiated adsorption sites because of alloying and the strain-induced modulation of the d-band center.

Sodium metal is a promising anode material for energy storage beyond lithium-ion batteries due to its abundance and low cost. However, the uncontrolled growth of dendrites and associated safety concerns have limited the practical application of sodium metal batteries (SMBs). By embedding nucleophilic tin seeds in a free-standing carbon film (FSF), here, an effective solution is developed to stabilize the sodium metal anode. The highly conductive and porous carbon matrix, intimately embedded with abundant Sn seeds (C@Sn), enables remarkably uniform sodium plating, and provides long-term stability for SMBs. Mechanistic studies confirm the formation of an Na─Sn alloy on interface which helps to lower the nucleation barrier for sodium plating. Hence, symmetric sodium cells equipped with C@Sn FSFs can sustain uninterrupted sodium plating and stripping for almost 2600 h at a high areal capacity of 4 mA h cm^-2, achieving an average Coulombic efficiency (CE) of 99.88%. In addition, full cells prepared with commercial Na₃V₂(PO₄)₃ cathode and C@Sn-FSFs anode deliver remarkable cycling (90 mA h g^-1 beyond 1300 cycles at 1C) and excellent rate performance. This ingenious strategy of embedding Sn particles within a carbon matrix offers an overall compelling solution to enhance the longevity of sodium anodes.

Inspired by the excellent photocatalytic activity of TiO₂, titanium metal-organic frameworks (Ti-MOFs) with broad absorption of visible light are regarded as promising photocatalysts, but carboxylate-linkers used in them are mainly limited to the large extended π-electron systems. Developing Ti-MOFs using organic linkers with a donor-acceptor-donor (D-A-D) structure is expected to improve their charge separation but is still challenging. Herein the design of two new isoreticular Ti-MOFs, Ti₆-SQ1 and Ti₆-SQ2 are reported, by using squaraines bearing different electron donors as organic linkers. Discrete fourier transform (DFT) calculations demonstrate that ligand-to-metal charge transfer (LMCT) from the acceptor units of squaraines to the Ti₆-oxo secondary building units (SBUs) drives the photocatalytic water splitting to hydrogen reaction. Compared with Ti₆-SQ2, the shorter distance between the squaraine centers and the Ti₆-oxo SBUs in Ti₆-SQ1 makes stronger LMCT, showing higher photocatalytic hydrogen evolution efficiency of 11.5 mmol g^-1 h^-1 under visible light (λ > 420 nm), which is ≈8 times that of Ti-based MOF photocatalysts reported so far. This work provides a new strategy to design Ti-MOF photocatalysts and understand their structure-property relationship.

Atopic dermatitis (AD) is a complex and prevalent chronic inflammatory skin disease that impacts a significant portion of the global population. Conventional treatments often focus on a singular pathogenic factor or suffer from limited skin penetration, resulting in unsatisfactory outcomes. Here, a multifunctional double-layered microneedle (MN) patch is proposed for long-term and effective treatment of AD by integrating therapeutic nanoparticles (NPs) and live bacteria. In the design, the MN tips are loaded with Prussian blue NPs encapsulating cetirizine hydrochloride (CET@PB NPs), while the patch backing incorporates Bacillus subtilis (B. subtilis). Upon skin insertion, the MN patch efficiently delivers CET@PB NPs into the skin and deposits live B. subtilis on the skin surface after fast dissolution. The delivered NPs not only scavenge reactive oxygen species (ROS) and improve oxidative stress microenvironments in the AD lesions, but also provide sustained release of the antihistamine CET in the skin for alleviating AD symptoms. Furthermore, B. subtilis survives on the skin for over 9 days and effectively inhibits the growth of the harmful bacteria Staphylococcus aureus. These features highlight the superior efficacy of the MN patch in long-term treatment of AD, offering a promising alternative for the management of skin disorders in clinics.