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Exploring single-atom catalysts (SACs) for the nitrate reduction reaction (NO3–; NitRR) to value-added ammonia (NH3) offers a sustainable alternative to both the Haber–Bosch process and NO3–-rich wastewater treatment. However, due to the insufficient electron deficiency and unfavorable electronic structure of SACs, resulting in poor NO3–-adsorption, sluggish proton (H*) transfer kinetics, and preferred hydrogen evolution, their NO3–-to-NH3selectivity and yield rate are far from satisfactory. Herein, a systematic theoretical prediction reveals that the local electron deficiency of an f-block Gd single atom (GdSA) can be significantly regulated upon coordination with oxygen-defect-rich NiO (GdSA-D-NiO400) support. Thus, facilitating stronger NO3–adsorption viastrong Gd5d–O2porbital coupling and further improving the protonation kinetics of adsorption intermediates by rapid H* capture from water dissociation catalyzed by the adjacent oxygen vacancy site along with suppressed H* dimerization synergistically boosts the NH3selectivity/yield rate. Motivated by DFT prediction, we delicately stabilized electron-deficient (strongly electrophilic) GdSAon D-NiO400(∼84% strong electrophilic sites), which exhibited excellent alkaline NitRR activity (NH3Faradaic efficiency ∼97% and yield rate ∼628 μg/(mgcath)) along with superior structural stability, as revealed by in situRaman spectroscopy, significantly outperforming weakly electrophilic Gd nanoparticles, defect-free GdSA-P-NiO400, and reported state-of-the-art catalysts.

We developed a new green phosphorescent iridium (III) complex, bis[2‐(9‐ethyl‐9H‐carbazol‐3‐yl)‐1‐methyl‐1H‐benzo[d]imidazole]iridium(III) acetylacetonate [(Bic)2Ir(acac)], which functions as a solution‐processable dopant for organic light‐emitting diodes (OLEDs). 2‐(9‐Ethyl‐9H‐carbazol‐3‐yl)‐1‐methyl‐1H‐benzo[d]imidazole was incorporated as the main ligand, while acetylacetone was introduced as an ancillary ligand in the heteroleptic iridium (III) complex. The molecular structure of the synthesized (Bic)2Ir(acac) was characterized by 1H‐ and 13C‐NMR. In addition, it was well soluble in common organic solvents, suitable for solution processible dopant material. The Ir (III) complex exhibited a green emission in solution state (dichloromethane) with an emission maximum at 503 nm. The solution‐processed OLED device using (Bic)2Ir(acac) as a green dopant achieved an external quantum efficiency of 6.85%, with a power efficiency of 14.96 lm/W, a maximum luminous efficiency of 23.00 cd/A, and Commission Internationale de Eclairage coordinates of (0.30, 0.61) at 7 wt% doping concentration. The new green phosphorescent Ir(III) complex, (Bic)2Ir(acac) was developed as a solution‐processible dopant for organic light‐emitting diode (OLED) and the device performances were investigated.

Two-dimensional (2D) transition metal dichalcogenides have received considerable attention due to their exotic electrical, chemical, and physical properties. Here, we report a layer-dependent band structure of a 2D semiconducting ternary metal chalcogenide (TMC), hexagonal FeIn2S4(hFIS), which is prepared through thickness-controlled colloidal solution synthesis. The controlled dissociation rate of chalcogen precursors caused the growth of the different thicknesses of hFIS, which is coincident with mechanisms established in conventional 2D nanomaterial colloidal synthesis. The various thickness-dependent band structures of hFIS were investigated from the corresponding optical band gap and redox potentials. The unveiled layer-dependent band structure of hFIS showed band gaps of approximately 1.02, 1.26, and 1.52 eV, corresponding to synthesis of the 7–8, 5–6, and 2–3 layers, respectively. This study will contribute to the exploration of other layer-dependent TMCs (MIn2X4, M = Fe, Co, Mn, and Zn and X = S, Se, and Te) for new optical and electronic device applications.

The design of cost-effective, highly active catalysts for hydrogen energy production is a vital element in the societal pursuit of sustainable energy. Water electrolysis is one of the most convenient processes to produce high purity hydrogen. Cobalt-based catalysts are well-known electrocatalysts for oxygen evolution reaction (OER). In this article, all these merits indicate that the present cobalt nanocomposite is a promising electrocatalyst for OER. CCo3O4-nanorods catalyst with nanorod structure was synthesized by hydrothermal treatment of CoCl2.6H2O/dextrose/urea mixture at 180°C for 18h and then calcined at 400°C for 3.5h. The role of dextrose percentage in solution to achieve the uniform coating of carbon on the surface of Co3O4-nanorods has been demonstrated. The prepared materials were characterized by X-ray diffraction (XRD), X-ray photoelectron spectrum (XPS), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), and Brunauer–Emmett–Teller instrument (BET). Due to its unique morphology, the CCo3O4-nanorods catalyst exhibited better activity than Co3O4-microplates catalyst for OER in 1M KOH aqueous solution. The results showed a highly efficient, scalable, and low-cost method for developing highly active and stable OER electrocatalysts in alkaline solution.

Controllable metal–support interaction (MSI) modulations have long been studied for improving the performance of catalysts supported on metal oxides. However, the corresponding in-depth study for metal1-metal2(M1-M2) composited configurations is rarely achieved due to the lack of reliable models and manipulation mechanisms of MSI modifications. We modeled ruthenium on copper support (Ru–Cu) metal catalysts with negligible interfacial contact potential (e0.06 V) and investigated MSI-dependent hydrogen evolution reaction (HER) catalysis kinetics induced by an electronic hydroxyl (HO-) modifier. Comprehensive simulations and characterizations confirmed that adjusting the HO- coverage can readily realize the tailorable improvement of MSI, facilitating charge migration at the Ru–Cu interface and optimizing the overall HER pathway on active Ru. As a result, a 5/10 monolayer (ML) HO-modified catalyst (5/10 ML) exhibits superior HER activity and durability owing to the relatively stronger MSI. This catalyst also ensured sustainable and efficient hydrogen generation in a urea electrolyzer with significant energy savings. Our work provides a valuable reference for optimizing the MSI-activity relationship in M1-M2catalysts that target more than just HER.

Dissociated primary neuronal cell culture remains an indispensable approach for neurobiology research in order to investigate basic mechanisms underlying diverse neuronal functions, drug screening and pharmacological investigation. Compartmentalization, a widely adopted technique since its emergence in 1970s enables spatial segregation of neuronal segments and detailed investigation that is otherwise limited with traditional culture methods. Although these compartmental chambers (e.g. Campenot chamber) have been proven valuable for the investigation of Peripheral Nervous System (PNS) neurons and to some extent within Central Nervous System (CNS) neurons, their utility has remained limited given the arduous manufacturing process, incompatibility with high-resolution optical imaging and limited throughput. The development in the area of microfabrication and microfluidics has enabled creation of next generation compartmentalized devices that are cheap, easy to manufacture, require reduced sample volumes, enable precise control over the cellular microenvironment both spatially as well as temporally, and permit highthroughput testing. In this review we briefly evaluate the various compartmentalization tools used for neurobiological research, and highlight application of the emerging microfluidic platforms towards in vitro single cell neurobiology.

Efficient transition metal oxide electrocatalysts for the alkaline hydrogen evolution reaction (HER) have received intensive attention to energy conversion but are limited by their sluggish water dissociation and unfavorable hydrogen migration and coupling. Herein, systematic density functional theory (DFT) predicts that on representative NiO, the hydroxylation (OH–) and heterointerface coupled with metallic Cu can respectively reduce the energy barrier of water dissociation and facilitate hydrogen spillover. Motivated by theoretical predictions, we subtly designed a delicate strategy to realize the electrochemical OH–modification in KOH with moderate concentration (HOM-NiO) and to channel rapid hydrogen spillover at the heterointerface of HOM-NiO and Cu, ensuring an enhanced HER kinetic. This HOM-NiO/Cu is systematically investigated by in situXAS and electrochemical simulations, verifying its extraordinary merits for HER including the enhanced water dissociation, alleviated oxophilicity that is advantageous for consecutive adsorptions of water, and accelerated hydrogen spillover, thereby exhibiting superb HER activity with 33 and 310 mV overpotentials at the current densities of 10 and 1000 mA cm–2in 1.0 M KOH, outperforming the Pt/C. This study might provide a reasonable strategy for the functionalized design of superior electrocatalysts.