A self-supported porous NiMo electrocatalyst to boost the catalytic activity in the hydrogen evolution reaction.

To develop hydrogen energy production and address the issues of global warming, inexpensive, effective, and long-lasting transition metal-based electrocatalysts for the synthesis of hydrogen are crucial. Herein, a porous electrocatalyst NiMo/Ni/NF was successfully constructed by a two-step electrodeposition process, and was used in the hydrogen evolution reaction (HER) of electrocatalytic water decomposition. NiMo nanoparticles were coated on porous Ni/NF grown on nickel foam (NF), leading to a resilient porous structure with enhanced conductivity for efficient charge transfer, as well as distinctive three-dimensional channels for quick electrolyte diffusion and gas release. Notably, the low overpotential (42 mV) and fast kinetics (Tafel slope of 44 mV dec-1) at a current density of 10 mA cm-2 in 1.0 M KOH solution demonstrate the excellent HER activity of the electrode, which was superior to that of recently reported non-noble metal-based catalysts. Additionally, NiMo/Ni/NF showed extraordinary catalytic durability in stability tests at a current density of 10 mA cm-2 for 70 h. The porous structure catalyst and the electrodeposition-electrocatalysis technique examined in this study offer new approaches for the advancement of the electrocatalysis field because of these benefits.

Electrolyzing spent cupronickel to fabricate superhydrophilic electrocatalysts for enhanced water splitting.

Herein, novel and efficient IF-supported NiCu (NiCu/IF) and NiMn (NiMn/IF) electrocatalysts are successfully deposited on iron foam (IF) via electrolysis of spent cupronickel (SCN), with outstanding performance for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) in an alkaline solution, respectively. The physical and electrochemical characterization results demonstrate that the catalysts possess a large active surface area, remarkable performance, and excellent durability.

One-step electrodeposition of V-doped NiFe nanosheets for low-overpotential alkaline oxygen evolution.

As a non-noble metal electrocatalyst for the oxygen evolution reaction (OER), the binary NiFe layer double hydroxide (LDH) is expected to replace Ru-based and Ir-based anode materials for water decomposition. To attain threshold current density, nevertheless, a somewhat significant overpotential is still needed. In this work, layered double hydroxides of NiFe LDH are doped with V to form the terpolymer NiFeV LDH, which greatly increases the intrinsic activity of NiFe LDH and improves OER performance. This process is a straightforward and quick one-step electrodeposition process. Notably, NiFeV/NF has a low overpotential (218 mV at 10 mA cm-2) and faster kinetics (Tafel slope of 31 mV dec-1) as well as excellent durability and stability in 1 M KOH solution. In addition, the OER performance of the catalyst prepared in this work is better than that of a non-valuable metal catalyst that was recently reported. The V-doped NiFe LDH layered double hydroxides and the investigation of electrodeposition electrocatalytic methods in this work offer a fresh opportunity for the advancement of electrochemical technology.

Limitations of lumbar spine MRI in the diagnosis of ankylosing spondylitis.

OBJECTIVES: To assess the value of inflammatory and fatty lesions in the lumbar spine on magnetic resonance imaging (MRI) in differentiating ankylosing spondylitis (AS) from non-inflammatory chronic back pain. METHODS: We reviewed the lumbar spine MR images of 192 consecutive AS patients and 208 non-AS subjects with non-inflammatory chronic back pain. Lesions including vertebral corner inflammatory lesions (CIL), inflammation in posterior elements (PE) of the spine, and fatty deposition lesions (FDL) seen on lumbar spine MRI were scored in a blinded manner. RESULTS: The frequencies of CIL and FDL in AS patients were higher than that in non-AS patients (both p<0.01), but there was no significant difference in the positive rate of inflammation in PE of the spine between two groups. AS patients had higher scores of all three types of lesions than non-AS patients (all p<0.01). Positive likelihood ratio increased as the cut-off score for distinguishing AS from other diseases increased (ranged from 1.14 to 18.42). But the biggest value of area under the receiver operating characteristic curve of all types of lesions was only 62.58%. We also summarised some features of these lesions that may help to distinguish AS from non-inflammatory chronic back pain. CONCLUSIONS: Our study found that the value of inflammatory and fatty lesions (including CIL, inflammation in PE and FDL) seen on lumbar spine MRI in the diagnosis of AS was limited. But the diagnosis of AS would be more convincing if patients had high scores of these three types of lesions (CIL ≥16, and/or inflammation in PE of the spine ≥5, and/or FDL ≥2).