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Transition metal phosphides (TMPs) are promising hydrogen evolution reaction (HER) electrocatalysts, but the unsatisfying activity and durability at industrial‐scale current densities hinder their application. Downsizing TMPs to nanoclusters can substantially enhance their activity; yet, the high surface free energy tends to initiate agglomeration thereby limiting their service life. Herein, a molecular engineering strategy to synthesize robust sulfur‐doped RuP2 (S‐RuP2) nanoclusters, which can continuously provide ampere‐level current densities of 1.0, 2.0, and 3.0 A cm−2 for at least 480 h with low overpotentials of 55.6 ± 1.0, 90.6 ± 1.2, and 122.8 ± 1.0 mV, respectively, is proposed. In particular, it exhibits a remarkable charge transfer amount (representing a long service life), outperforming all reported alkaline HER electrocatalysts. Remoulding the RuP2 architecture by sulfur atom can significantly lift the d‐band center of Ru and the p‐band center of P, therefore strengthening the adsorption of H2O, H, and OH to reduce the barriers of water dissociation and H migration. The authors‘ research unveils the enormous potential of molecule‐based porous materials for designing high‐performance nano‐structured catalysts. [ABSTRACT FROM AUTHOR]

Biodiversity endows similar species with subtle differences in composition, microstructure, and surface chemistry, making biomass a promising precursor to control the resulting active structure for heterocatalysis. Here, it is shown that Tremella fuciformis (Tfu), possessing an abundant porous structure and favorable metal affinity, is favorably serves as a precursor for confining uniform metal nanoparticles, by comparing the chemical characteristics of six varieties of agarics. The modest size of Co in the Tfu derived composite, Co@NPC‐Tfu (NPC = N, P co‐doped carbon), is suitable for in situ semi‐oxidation during oxygen evolution reaction (OER), forming a stable core‐shell structure of Co3O4@Co. Thus, Co@NPC‐Tfu can be used as a state‐of‐the‐art electrocatalyst for OER with an overpotential of 213.6 ± 4.1 mV at 10 mA cm−2, and a significant turnover frequency of 3.21 s−1 at 300 mV, benefitting from the optimum trade‐off between the atom utilization and electrical conductivity. Operando spectroscopy and theoretical calculations unveil the occupied state modulation of the robust carbon‐bonded POx groups, which optimizes the intermediate adsorption to accelerate OER kinetics. Moreover, Tfu derived Ni@NPC‐Tfu can be also prepared as a high‐performance hydrogen evolution reaction electrocatalyst, which can be utilized for efficient overall water splitting coupled with Co@NPC‐Tfu. [ABSTRACT FROM AUTHOR]

Cobalt imidazolate frameworks are classical electrocatalysts for the oxygen evolution reaction (OER) but suffer from the relatively low activity. Here, a non‐3d metal modulation strategy is presented for enhancing the OER activity of cobalt imidazolate frameworks. Two isomorphous frameworks [Co4(MO4)(eim)6] (M=Mo or W, Heim=2‐ethylimidazole) having Co(eim)3(MO4) units and high water stabilities were designed and synthesized. In different neutral media, the Mo‐modulated framework coated on a glassy carbon electrode shows the best OER performances (1 mA cm−2 at an overpotential of 210 mV in CO2‐saturated 0.5 m KHCO3 electrolyte and 2/10/22 mA cm−2 at overpotential of 388/490/570 mV in phosphate buffer solution) among non‐precious metal catalysts and even outperforms RuO2. Spectroscopic measurements and computational simulations revealed that the non‐3d metals modulate the electronic structure of Co for optimum reactant/product adsorption and tailor the energy of rate‐determining step to a more moderate value. Non‐3D for 3D: Introducing non‐3d metal oxide units into a cobalt imidazolate framework results in the drastic enhancement of electrocatalytic performance of the oxygen evolution reaction in neutral media. [ABSTRACT FROM AUTHOR]

Coordination polymers (CPs) are ideal precursors for synthesizing porous catalysts. However, the direct thermolysis of CPs is prone to generate agglomerates, greatly reducing the electrical conductivity and active sites of their derived catalysts. The construction of well‐ordered CP nanostructures is a promising strategy for alleviating the above issue, but it remains challenging. Here, a facile chemical etching approach is developed for the fabrication of well‐aligned three‐dimensional (3D) bimetallic Prussian blue‐analogue nanosheet arrays. Impressively, the derived porous metal oxide (Fe–NiO) acts as a remarkable oxygen evolution reaction (OER) catalyst, which merely requires overpotentials as low as 218 and 270 mV to achieve 10 and 100 mA cm−2 in 1.0 m KOH aqueous solution, respectively. The excellent electrocatalytic performance of Fe–NiO is ascribed to the 3D porous nanosheet array architecture, which endows the bimetallic catalyst with abundant electrocatalytic active sites, enhanced surface permeability, and high electronic conductivity. It is expected that the proposed strategy can pave a new way for fabricating highly efficient electrocatalysts for energy storage and conversion. A piece of art: Well‐ordered 3D bimetallic Prussian blue analogue nanosheet arrays are fabricated by etching Ni(OH)2 nanosheet arrays with potassium ferricyanide. The derived porous electrocatalyst exhibits excellent electrochemical activity and stability for the oxygen evolution reaction with overpotentials as low as 218 and 270 mV to achieve 10 and 100 mA cm−2 in 1.0 m KOH solution, respectively. [ABSTRACT FROM AUTHOR]

Background and Aims Bronchoscopy is an important method for diagnosing respiratory disease. Multiple tracheobronchial nodules are rarely reported and their causes remain unclear. Objectives The aim of this study was to describe the clinical characteristics of multiple nodule tracheobronchial abnormalities found under bronchoscopy caused by different diseases. Methods Eighty-seven patients with multiple tracheobronchial nodules were enrolled in this study. The characteristics of the multinodule lesions and the patient were diagnosed based on the pathology findings in our hospital. Chest computed tomography images were retrospectively reviewed by pulmonologists and radiologist. Results In 55 patients with definite pathological diagnosis, 16 (29%) patients were diagnosed as tuberculosis (TB) granuloma; 23 (41.8%) cases were diagnosed as malignant disease; 12 (21.8%) cases were diagnosed as tracheobronchopathia osteochondroplastica; 2 (3.6%) cases were diagnosed as sarcoidosis; and one case (1.8%) was diagnosed as lymphoma and one case (1.8%) as fungal infection. There were 32 cases of chronic inflammation. There was no relationship between nodule distribution and the pathological diagnosis. Malignant nodules usually smaller with a pale outlook, while nodules with larger size and smooth and intact mucosa usually turn out to be granuloma of unknown reason. Conclusion The major causes of mutinodule lesions observed using bronchoscopy are tumor and TB. The presence of multiple endotracheobronchial nodules suggest that pulmonary lesion is present, and biopsy should be performed. Malignant nodules can be diagnosed by appearance and biopsy. Pathology results of TB, sarcoidosis and fungal infection can turn out to be granuloma of unknown reason. Further diagnosis needs other clinical materials. [ABSTRACT FROM AUTHOR]

Industrial application of overall water splitting requires developing readily available, highly efficient, and stable oxygen evolution electrocatalysts that can efficiently drive large current density. This study reports a facile and practical method to fabricate a non‐noble metal catalyst by directly growing a Co‐Fe Prussian blue analogue on a 3D porous conductive substrate, which is further phosphorized into a bifunctional Fe‐doped CoP (Fe‐CoP) electrocatalyst. The Fe‐CoP/NF (nickel foam) catalyst shows efficient electrocatalytic activity for oxygen evolution reaction, requiring low overpotentials of 190, 295, and 428 mV to achieve 10, 500, and 1000 mA cm−2 current densities in 1.0 m KOH solution. In addition, the Fe‐CoP/NF can also function as a highly active electrocatalyst for hydrogen evolution reaction with a low overpotential of 78 mV at 10 mA cm−2 current density in alkaline solution. Thus, the Fe‐CoP/NF electrode with meso/macropores can act as both an anode and a cathode to fabricate an electrolyzer for overall water splitting, only requiring a cell voltage of 1.49 V to afford a 10 mA cm−2 current density with remarkable stability. This performance appears to be among the best reported values and is much better than that of the IrO2‐Pt/C‐based electrolyzer. A gentle and practical pathway is reported to fabricate efficient, non‐noble metal catalyst by directly growing a bimetallic prussian blue analogue 3D conductive substrate, phosphorized into a 3D bifunctional hierarchical‐pore Fe‐CoP electrocatalyst. The as‐obtained Fe‐CoP can drive large‐current‐density oxygen evolution and efficiently catalyze overall water splitting. [ABSTRACT FROM AUTHOR]