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The oxidative degradation of plastics in conjunction with the production of clean hydrogen (H₂) represents a significant challenge. Herein, a Ni₃S₄/ZnCdS heterojunction is rationally synthesized and employed for the efficient production of H₂ and high-selectivity value-added chemicals from waste plastic. By integrating spectroscopic analysis techniques with density functional theory (DFT) calculations, a solely electron transfer-mediated reaction mechanism is confirmed, wherein Ni₃S₄ extracts electrons from ZnCdS (ZCS) to promote the spatial segregation of photogenerated electrons and holes, which not only facilitates H₂ production but also maintains the high oxidation potential of holes on the ZCS surface, favoring hole-dominated plastic oxidation. Notably, the catalyst exhibited efficient H₂ production rates as high as 27.9 and 17.4 mmol g^-1 h^-1, along with a selectivity of 94.2% and 78.3% in the liquid product toward pyruvate and acetate production from polylactic acid (PLA) and polyethylene terephthalate (PET), respectively. Additionally, carbon yields of 26.5% for pyruvate and 2.2% for acetate are measured after 9 h of photoreforming, representing the highest values reported to date. Overall, this research presents a promising approach for converting plastic waste into H₂ fuel and high-selectivity valuable chemical products, offering a potential solution to the growing issue of "White Pollution".

The in-depth investigation of the structure–property relationship in porous organic cages (POCs) for real gas mixture separation is both significant and challenging. In this work, we employed microenvironment modulation strategy to systematically regulate the gas adsorption and separation performance of POCs. The introduction of amino groups into the cavity of [2 + 4] lantern-shaped POC (CPOC-108) can effectively facilitate multiple host–guest interactions in confined cavities via forming hydrogen bond interactions. The as-prepared amino-functionalized POC (CPOC-108-NH₂) thus exhibits remarkably enhanced C₂H₂ and CO₂ adsorption capacities, especially for the more polarizable C₂H₂ gas, as well as higher C₂H₂/CO₂ selectivity in comparison to CPOC-108. More importantly, CPOC-108-NH₂ displays significantly improved separation performance for C₂H₂/CO₂ mixture, as evidenced by dynamic breakthrough experiments. This work provides an elegant example for a comparative study on C₂H₂/CO₂ separation properties between amino-functionalized and unsubstituted POCs, and may shed light on fine-tuning the cavity surfaces of POCs to rationally regulate their properties.

Strong metal-support interactions (SMSIs) are important in heterogeneous catalysis to control stability, activity, and selectivity. Core-shell nanostructures as a unique SMSI system not only stabilize the metal nanoparticles in the core, but also offer tunable structural and electronic properties via their interaction with the support shell. The Au@NiO_x core-shell system, for example, is the first commercial nanogold catalyst to produce bulk chemicals via the oxidative esterification of aldehydes. However, how the SMSI effect in Au@NiO_x manifests on its oxidative esterification activity is unclear. Here we use a model of an Au₁₃@(NiO)₄₈ core-shell nanocatalyst to examine the Au-NiO interaction and the associated electronic and geometric factors in enabling the oxidation of a hemiacetal (an intermediate from a ready reaction between an aldehyde and an alcohol) to an ester. We found 1.27 (e^-) electrons flowing from the NiO shell to the Au core, leading to a higher oxide state of Ni atoms and the stabilization of key intermediates on the NiO shell. More importantly, lower activation energy was found on the Au₁₃@(NiO)₄₈ catalyst than on the Au(111) and NiO(100) surfaces for the rate-limiting step. Microkinetic modeling confirmed the high activity of the Au₁₃@(NiO)₄₈ catalyst in ester production in the experimental temperature range. Our work demonstrates the unique geometric and electronic effects of the Au@NiO_x core-shell nanostructure on the catalytic oxidative esterification of aldehydes.

A water oxidation catalyst Ru-bcs (bcs = 2,2′-bipyridine-6′-carboxylate-6-sulfonate) with a hybrid ligand was reported. Ru-bcs utilizes the electron-donating properties of carboxylate ligands and the on-demand coordination feature of sulfonate ligands to enable a low onset potential of 1.21 V vs. NHE and a high TOF over 1000 s⁻¹ at pH 7. The adaptive chemistry uncovered in this work provides new perspectives for developing molecular catalysts with high efficiency under low driving forces.

Inspired by the function of crucial components in photosystem II (PSII), electrochemical and dyesensitized photoelectrochemical (DSPEC) water oxidation devices were constructed by the selfassembly of well-designed amphipathic Ru(bda)-based catalysts (bda = 2,2'-bipyrdine-6,6'-dicarbonoxyl acid) and aliphatic chain decorated electrode surfaces, forming lipid bilayer membrane (LBM)-like structures. The Ru(bda) catalysts on electrode-supported LBM films demonstrated remarkable water oxidation performance with different O-O formation mechanisms. However, compared to the slow charge transfer process, the O-O formation pathways did not determine the PEC water oxidation efficiency of the dyesensitized photoanodes, and the different reaction rates for similar catalysts with different catalytic paths did not determine the PEC performance of the DSPECs. Instead, charge transfer plays a decisive role in the PEC water oxidation rate. When an indolo[3,2-b] carbazole derivative was introduced between the Ru (bda) catalysts and aliphatic chain-modified photosensitizer in LBM films, serving as a charge transfer mediator for the tyrosine-histidine pair in PSII, the PEC water oxidation performance of the corresponding photoanodes was dramatically enhanced.

The determination of catalytically active sites is crucial for the design of efficient and stable catalysts toward desired reactions. However, the complexity of supported noble metal catalysts has led to controversy over the locations of catalytically active sites (e.g., metal, support, and metal/support interface). Here we develop a structurally controllable catalyst system (Pd/SBA-15) to reveal the catalytic active sites for the selective hydrogenation of ketones to alcohol using acetophenone hydrogenation as model reaction. Systematic investigations demonstrated that unsupported Pd nanocrystals have no catalytic activity for acetophenone hydrogenation. However, oxidized Pd species were catalytically highly active for acetophenone hydrogenation. The catalytic activity decreased with the decreased oxidation state of Pd. This work provides insights into the hydrogenation mechanism of ketones but also other unsaturated compounds containing polar bonds, e.g., nitrobenzene, N-benzylidene-benzylamine, and carbon dioxide.

Despite extensive research on water oxidation catalysts over the past few decades, the relationship between high-valent metal-oxo intermediates and the O-O bond formation pathway has not been well clarified. Our previous study showed that the high spin density on O in Ru^V=O is pivotal for the interaction of two metal-oxyl radical (I2M) pathways. In this study, we found that introducing an axially coordinating ligand, which is favorable for bimolecular coupling, into the Ru-pda catalyst can rearrange its geometry. The shifts in geometric orientation altered its O-O bond formation pathway from water nucleophilic attack (WNA) to I2M, resulting in a 70-fold increase in water oxidation activity. This implies that the I2M pathway is concurrently influenced by the spin density on oxo and the geometry organization of the catalysts. The observed mechanistic switch and theoretical studies provide insights into controlling reaction pathways for homogeneous water oxidation catalysis.

Metal ions play a central, functional, and structural role in many molecular structures, from small catalysts to metal–organic frameworks (MOFs) and proteins. Computational studies of these systems typically employ classical or quantum mechanical approaches or a combination of both. Among classical models, only the covalent metal model reproduces both geometries and charge transfer effects but requires time-consuming parameterization, especially for supramolecular systems containing repetitive units. To streamline this process, we introduce metallicious, a Python tool designed for efficient force-field parameterization of supramolecular structures. Metallicious has been tested on diverse systems including supramolecular cages, knots, and MOFs. Our benchmarks demonstrate that parameters accurately reproduce the reference properties obtained from quantum calculations and crystal structures. Molecular dynamics simulations of the generated structures consistently yield stable simulations in explicit solvent, in contrast to similar simulations performed with nonbonded and cationic dummy models. Overall, metallicious facilitates the atomistic modeling of supramolecular systems, key for understanding their dynamic properties and host–guest interactions. The tool is freely available on GitHub (https://github.com/duartegroup/metallicious).

Metal halide perovskite materials inherently possess imperfections, particularly under nonequilibrium conditions, such as exposure to light or heat. To tackle this challenge, we introduced stearate ligand-capped nickel oxide (NiO_x), a redox-sensitive metal oxide with variable valence, into perovskite intermediate films. The integration of NiO_x improved the efficiency and stability of perovskite solar cells (PSCs) by offering multifunctional roles: (1) chemical passivation for ongoing defect repair, (2) energetic passivation to bolster defect tolerance, and (3) field-effect passivation to mitigate charge accumulation. Employing a synergistic approach that tailored these three passivation mechanisms led to a substantial increase in the devices’ efficiencies. The target cell (0.12 cm²) and module (18 cm²) exhibited efficiencies of 24.0 and 22.9%, respectively. Notably, the encapsulated modules maintained almost 100 and 87% of the initial efficiencies after operating for 1100 h at the maximum power point (60 °C, 50% RH) and 2000 h of damp-heat testing (85 °C, 85% RH), respectively. Outdoor real-time tests further validated the commercial viability of the NiO_x-assisted PSMs. The proposed passivation strategy provides a practical and uncomplicated approach for fabricating high-efficiency and stable photovoltaics.

Charge accumulations and electron recombination at the interfaces between perovskites and charge transporting materials are two critical factors significantly hindering the power conversion efficiency (PCE) and device stability of wide-bandgap perovskite solar cells (WBG PSCs). Herein, we tailor-made a self-assembled molecule (SAM), termed XS13, featuring an enlarged π-donor and a π-linker, to regulate the interface carrier dynamics in ∼1.8 eV WBG PSCs. Ultrafast spectroscopy clearly demonstrated that the XS13 facilitated the rapid extraction and transfer of photo-generated holes compared to the reference SAM-2PACz. Consequently, WBG PSCs based on XS13 achieved an outstanding PCE of up to 19.20 %, surpassing that of control devices (16.41 %). Furthermore, XS13-based WBG PSCs exhibited a remarkable suppression of light/electricity-induced halide ions migration, leading to significantly improved device stability. Our findings offer a new strategy for the rational design of hole transporting molecules with controlled properties to enhance device performance of PSCs.