Bin Xi

The weak interactions between powdered catalysts and their supports significantly impact the kinetics of the water electrolysis oxidation reaction. Here, we use plasma‐enhanced atomic layer deposition (PEALD) technology to directly construct amorphous carbon‐doped gallium oxide (ACG) on a glassy carbon (GC) electrode with trimethylgallium (TMGa) and oxygen plasma as oxygen sources. The technique has low saturation pulse periods for the TMGa precursor, a wide temperature range (75°C–300°C), and a steady growth rate of 0.65 Å/cycle. Carbon atom doping induces localized electric fields within the ACG, enhancing the kinetics of the water electrolysis reaction. In addition, electron paramagnetic resonance spectroscopy and theoretical calculations show that ACG forms a catalyst–water–heterojunction structure with water molecules, which promotes the formation of hydroxyl radicals, thus revealing the active origin of GaOOH. Importantly, under the strong oxidizing effect of hydroxyl radicals, carbonate is easily formed, and a weak alkaline layer is formed at the interface of the catalyst, which prevents continuous reconstruction of the GaOOH phase, thus improving the stability of the catalyst in complex media. Meanwhile, it is revealed that ACG follows the lattice oxygen mechanism in the oxygen evolution reaction process. Results indicate that achieving a current of 1000 mA cm ⁻² in an alkaline seawater medium requires only 1.94 V, with stable operation for 200 h showing virtually no attenuation. This study demonstrates the ability to manufacture thin films via PEALD, paving the path toward enhanced electrocatalytic applications.

Precise tuning of phase transition material properties enables multifunctional devices for information processing and energy conversion, but controlling on-device phase transitions and monitoring microscopic mechanisms remains challenging. Here, we develop a lab-on-device system for molybdenum oxide to probe operando hydrogenation mechanisms through in situ electrical and spectral characterization with density functional theory calculations, revealing threshold-driven proton dynamics that govern the transition between nonvolatile memory operation and catalytic hydrogen evolution. Moderate proton intercalation (flux < 10¹⁷cm^-2) achieves a five-order conductance modulation under ambient conditions via polaron formation and stoichiometric optimization (H/Mo up to 22%, Mo/O approaching ideal ratios), outperforming oxygen vacancy engineering. Beyond this threshold (flux ~10¹⁷ cm^-2), intensive proton intercalation triggers electric-to-chemical energy conversion, directly linking proton history to catalytic activity. Leveraging these principles, we achieve nonvolatile electrochemical memory with linear synaptic and accumulative neuronal functionalities, and demonstrate an all electrochemical random-access memory neural network hardware that executes memory-efficient rank-order coding for sparse signals even under noisy conditions.

Mechanochemical gating of chemical reactions has promising potential for applications ranging from controlled polymer degradation to triggered drug release, but it remains underexplored. A mechanochemically gated molecular probe can be developed by masking either its receptor or reporter with a mechanophore, extending the concept of mechanochemical gating to chemical sensing. Here we demonstrate this concept by reporting a latent fluorescent probe with an anthracene-maleimide Diels-Alder adduct mechanophore as the masked fluorophore and an aza-crown ether as the receptor. Upon mechanochemical activation, the mechanophore undergoes a retro-Diels-Alder reaction, exposing the fluorophore and thus activating the probe for cations (potassium ions in particular) based on N-(9-anthracenylmethyl)aza-18-crown-6. We believe that this work establishes a general design principle for mechanochemically gated probes, advancing the development of smart stress and chemical sensing systems.

In this study, we present atomic layer deposition (ALD) of nickel oxides (NiO_x) using a new nickel precursor, (methylcyclopentadienyl)(cyclopentadienyl)nickel (NiCp(MeCp)), and ozone (O₃) as the oxygen source. The process features a relatively short saturation pulse of the precursor (NiCp(MeCp)) and a broad temperature window (150–250 °C) with a consistent growth rate of 0.39 Å per cycle. The NiO_x film deposited at 250 °C primarily exhibits a polycrystalline cubic phase with minimal carbon contamination. Notably, the post-annealed ALD NiO_x film demonstrates attractive electrocatalytic performance on the oxygen evolution reaction (OER) by providing a low overpotential of 320 mV at 10 mA cm⁻², a low Tafel slope of 70.5 mV dec⁻¹, and sufficient catalytic stability. These results highlight the potential of the ALD process using the NiCp(MeCp) precursor for the fabrication of high-activity catalysts.

Flex-activated mechanophores capable of releasing small molecules utilize bond bending to facilitate their mechanochemical activation without compromising the overall macromolecular architecture, which have great potential in various applications. However, the development of such mechanophores remains underexplored. Here we report a novel flex-activated mechanophore based on the 1,4-Diels-Alder (DA) adduct of 9,10-diphenylanthracene (DPA) with acetylenedicarboxylate (ADC). Compression of the mechanophore-crosslinked polymer networks mechanochemically activates the weakly fluorescent DPA-ADC mechanophores to undergo a retro-DA reaction in accompany with the release of highly fluorescent DPA molecules (quantum yield close to unity), as confirmed by fluorescence spectroscopy and gas chromatography-mass spectrometry (GC-MS) analysis. As a new member of the small family of flex-activated mechanophores, this fluorogenic DPA-ADC mechanophore possesses promising applications in stress sensing and damage detection.

With the development of mechanophores, polymer mechanochemistry has emerged as a powerful tool for creating force‐responsive materials with a variety of desired functions, ranging from color change to molecular release. However, it remains challenging to improve the efficiency of mechanochemical activation, especially for mechanophores embedded within polymer networks, which has profound implications for translating mechanochemical responses into materials‐centered applications. The physical and chemical conditions under spatial confinement differ significantly from those in the surrounding bulk environment, offering opportunities to facilitate mechanochemical activation. In this Minireview, we discuss and summarize recent progress in polymer mechanochemistry within confined spaces including surfaces/interfaces, polymer assemblies, and other nanostructures, specifically focusing on the effects of spatial confinement on the enhancement of mechanophore activation. We envision that combining confinement effects with advances in molecular and materials engineering will further improve the activation efficiency, capitalizing more fully on the potential of mechanophores toward practical applications.

With the development of mechanophores, polymer mechanochemistry has emerged as a powerful tool for creating force‐responsive materials with a variety of desired functions, ranging from color change to molecular release. However, it remains challenging to improve the efficiency of mechanochemical activation, especially for mechanophores embedded within polymer networks, which has profound implications for translating mechanochemical responses into materials‐centered applications. The physical and chemical conditions under spatial confinement differ significantly from those in the surrounding bulk environment, offering opportunities to facilitate mechanochemical activation. In this Minireview, we discuss and summarize recent progress in polymer mechanochemistry within confined spaces including surfaces/interfaces, polymer assemblies, and other nanostructures, specifically focusing on the effects of spatial confinement on the enhancement of mechanophore activation. We envision that combining confinement effects with advances in molecular and materials engineering will further improve the activation efficiency, capitalizing more fully on the potential of mechanophores toward practical applications.

This mini-review details the research status of atomic-layer deposition in regulating the active interface of catalysts, and predicts its future development trends with regard to catalysis.