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The one-step hydroalkylation of benzene to cyclohexylbenzene (CHB) is a technically challenging and economically interesting reaction with great industrial importance, where bifunctional catalysts play a crucial role in such a tandem reaction. In this work, we report H3PW12O40(HPW) modified Ni nanoparticles (NPs) supported on mixed metal oxides (Ni/MMOs), which are featured by HPW species localized on the surface of Ni NPs (denoted as HPW-Ni/MMOs). The optimal catalyst (0.3HPW-Ni/MMOs) exhibits a satisfactory catalytic performance toward benzene hydroalkylation to CHB with a CHB yield of up to 41.2%, which is the highest standard among previously reported catalysts to date. A combination investigation based on HR-TEM, XPS, XANES, and in situFT-IR verified the electron transfer from the W atom to the adjacent Ni atom, which facilitated the formation and desorption of cyclohexene (CHE) from Ni followed by the alkylation reaction of benzene and CHE at the interfacial Brønsted (B) acid sites of HPW, accounting for the significantly enhanced catalytic behavior. It is proposed that the HPW-Ni interface structure in xHPW-Ni/MMOs samples provides unique adsorption sites for benzene and CHE with a moderate adsorption strength, which serve as the intrinsic active center for this reaction: the Ni site promotes the hydrogenation of benzene to CHE, while the B acid site in HPW facilitates the alkylation of CHE and benzene to produce CHB. This work provides a fundamental understanding of the metal–acid synergistic catalysis toward the hydroalkylation reaction, which can be extended to the design and preparation of high-performance catalysts used in tandem reactions.

With the growth of demand for flexible devices, the development of flexible electrodes used in energy storage devices has attracted much attention of researchers. In this work, a thin flexible cathode of Prussian blue analogue@polyaniline rooted in carbon cloth has been fabricated. The Prussian blue analogue (PBA) is an electrochemically active material grafted on flexible carbon cloth substrates, which had been precoated with polyaniline. Polyaniline as an intermediate layer can not only improve the overall electronic conductivity of the electrode but also enhance the adhesion and load of the PBAs. The electrochemical properties of the flexible cathode with a “sandwich” structure were determined in half-cells, with a superior capacity of 151 mA h·g–1and a striking cyclability with 96% capacity retention over 100 cycles at 100 mA h·g–1. This work proposes a novel perspective for the structural construction and material synthesis of flexible positive electrodes and gives new options for the practical application of flexible batteries.

Achieving dimethyl carbonate (DMC) direct synthesis from the reaction of CH3OH with CO2presents broad prospects in CO2conversion to value-added products, while the underlying reaction mechanism over the catalysts with oxygen vacancy (Ov) active centers has not been clearly revealed yet. Herein, we report Ovstructures fabricated on CeO2nanorods via a facile element doping route (denoted as MxCe1–xO2, x= 0, 0.05, M including Ca, Co, Fe, and Mn), and Ov-enriched Fe0.05Ce0.95O2presents a significantly higher methanol conversion (63.7%) and a DMC generation rate up to 802.8 mmol g–1h–1with a DMC selectivity (93.0%) among these catalysts, reaching the highest level compared with previously reported catalyst systems for the generation of DMC. HR-TEM, H2-TPR, Raman, and XPS measurements show the promotion effect of element doping into the CeO2nanorods on the formation of the surface oxygen vacancies (Ov). CO2-TPD and in situFT-IR of adsorbed methanol demonstrate that oxygen vacancies and an adjacent acidic site over MxCe1–xO2can effectively activate and convert CO2to long-chain chemicals. In situFT-IR further confirms that the promoted formation of the carbonic acid monomethyl ester (the key reaction intermediate) via the cooperation of Ovand a neighboring acidic site is responsible for the promising DMC synthesis activity over the MxCe1–xO2nanorods. The identification of the active sites of the oxidized Ovspecies in this system will potentially guide the design of an efficiently heterogeneous catalyst for CO2chemical conversion.

We report a simple, robust, and inexpensive strategy to enable all-inorganic CsPbX3perovskite nanocrystals (NCs) with a set of markedly improved stabilities, that is, water stability, compositional stability, phase stability, and phase segregation stability via impregnating them in solid organic salt matrices (i.e., metal stearate; MSt). In addition to acting as matrices, MSt also functions as the ligand bound to the surface of CsPbX3NCs, thereby eliminating the potential damage of NCs commonly encountered during purification as in copious past work. Quite intriguingly, the resulting CsPbX3–MSt nanocomposites display an outstanding suite of stabilities. First, they retain high emission in the presence of water because of the insolubility of MSt in water, signifying their excellent water stability. Second, anion exchange between CsPbBr3–MSt and CsPbI3–MSt nanocomposites is greatly suppressed. This can be ascribed to the efficient coating of MSt, thus effectively isolating the contact between CsPbBr3and CsPbI3NCs, reflecting notable compositional stability. Third, remarkably, after being impregnated by MSt, the resulting CsPbI3–MSt nanocomposites sustain the cubic phase of CsPbI3and high emission, manifesting the strikingly improved phase stability. Finally, phase segregation of CsPbBr1.5I1.5NCs is arrested via the MSt encapsulation (i.e., no formation of the respective CsPbBr3and CsPbI3), thus rendering pure and stable photoluminescence (i.e., demonstration of phase segregation stability). Notably, when assembled into typical white light-emitting diode architecture, CsPbBr1.5I1.5–MSt nanocomposites exhibit appealing performance, including a high color rendering index (Ra) and a low color temperature (Tc). As such, the judicious encapsulation of perovskite NCs into organic salts represents a facile and robust strategy for creating high-quality solid-state luminophores for use in optoelectronic devices.

Low-cost manganese hexacyanoferrate (NMHCF) possesses many favorable advantages including high theoretical capacity, ease of preparation, and robust open channels that enable faster Na+diffusion kinetics. However, high lattice water and low electronic conductivity are the main bottlenecks to their pragmatic realization. Here, we present a strategy by anchoring NMHCF on reduced graphene oxide (RGO) to alleviate these problems, featuring a specific discharge capacity of 161/121 mA h g–1at a current density of 20/200 mA g–1. Moreover, the sodiation process is well revealed by ex situ X-ray diffraction, EIS and Car–Parrinello molecular dynamics simulations. At a rate of 20 mA g–1, the hard carbon//NMHCF/RGO full cell affords a stable discharge capacity of 84 mA h g–1(based on the weights of cathode mass) over 50 cycles, thus highlighting NMHCF/RGO an alternative cathode for sodium-ion batteries.

The hydroalkylation tandem reaction of benzene to cyclohexylbenzene (CHB) provides an atom economy route for conversion and utilization of benzene; yet, it presents significant challenges in activity and selectivity control. In this work, we report a metal-support synergistic catalyst prepared viacalcination of W-precursor-containing montmorillonite (MMT) followed by Pd loading (denoted as Pd–mWOx/MMT, m= 5, 15, and 25 wt %), which shows excellent catalytic performance for hydroalkylation of benzene. A combination study (X-ray diffraction (XRD), hydrogen-temperature programmed reduction (H2-TPR), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV–vis, Raman, and density functional theory (DFT) calculations) confirms the formation of interfacial sites Pd–(WOx)–H, whose concentration is dependent on the interaction between Pd and WOx. The optimized catalyst (Pd–15WOx/MMT) exhibits a CHB yield of up to 45.1% under a relatively low hydrogen pressure, which stands at the highest level among state-of-the-art catalysts. Investigations on the structure–property correlation based on in situFT-IR and control experiments further verify that the Pd–(WOx)–H structure serves as the dual-active site: the interfacial Pd site accelerates benzene hydrogenation to cyclohexene (CHE), while the interfacial Bronsted (B) acid site in Pd–(WOx)–H boosts the alkylation of benzene and CHE to CHB. This study offers a new strategy for the design and preparation of metal–acid bifunctional catalysts, which shows potential application in the hydroalkylation reaction of benzene.

Understanding the interfacial behaviors of biomolecules is crucial to applications in biomaterials and nanoparticle-based biosensing technologies. In this work, we utilized autoencoder-based graph clustering to analyze discontinuous molecular dynamics (DMD) simulations of lysozyme adsorption on a graphene surface. Our high-throughput DMD simulations integrated with a Go̅-like protein–surface interaction model makes it possible to explore protein adsorption at a large temporal scale with sufficient accuracy. The graph autoencoder extracts a low-dimensional feature vector from a contact map. The sequence of the extracted feature vectors is then clustered, and thus the evolution of the protein molecule structure in the absorption process is segmented into stages. Our study demonstrated that the residue–surface hydrophobic interactions and the π–π stacking interactions play key roles in the five-stage adsorption. Upon adsorption, the tertiary structure of lysozyme collapsed, and the secondary structure was also affected. The folding stages obtained by autoencoder-based graph clustering were consistent with detailed analyses of the protein structure. The combination of machine learning analysis and efficient DMD simulations developed in this work could be an important tool to study biomolecules’ interfacial behaviors.

Dimensional gradient structure of sheet–tube–dots was constructed with CoSe2@CNTs–MXene for fast ion and electron transportation.Density functional theory study discloses the electrochemical difference of CoSe2@CNTs–MXene in ether/ester electrolyte system.Phase transformation of CoSe2@CNTs–MXene was analyzed by in situ XRD. The full cell based on CoSe2@CNTs–MXene anode was also assembled.

Catalytic conversion of a biomass derivative (levulinic acid, LA) to a high value-added product (γ-valerolactone, GVL) has attracted much attention, in which the control of catalytic selectivity plays an important role. Herein, a stepwise method was developed to prepare Co-MoOxcatalysts viatopological transformation (calcination reduction) from layered double hydroxide (Mo/CoAl-LDH) precursors. X-ray diffraction, high-resolution transmission electron microscopy, and hydrogen temperature-programmed reduction demonstrate the formation of MoOx-decorated Co structures of Co-MoOxsamples. Remarkably, the sample that is reduced at 500 °C is featured with the most abundant interfacial Coδ+(denoted as Co-MoOx-500), which exhibits an excellent catalytic performance toward the hydrodeoxygenation (HDO) reaction of several biomass-derived platform molecules (furfural, FAL; succinic acid, SA; 5-hydroxymethyl-furfural, HMF; and levulinic acid, LA). Especially, this optimal catalyst displays a high yield (99%) toward the HDO reaction of LA to GVL, which stands at the highest level among non-noble metal catalysts. The combination of in situFT-IR characterization and theoretical calculation further confirms that interfacial Coδ+sites in Co-MoOx-500 act as adsorption active sites for the polarization of a C═O bond in an LA molecule, which simultaneously promotes C═O hydrogenation and C—O cleavage. Moreover, the MoOxoverlayer suppresses the formation of byproducts by covering the Co0sites. This work offers a cost-effective and efficient catalyst, which can be potentially applied in catalytic conversion of biomass-derived platform molecules.