Inter-Metal Interaction with a Threshold Effect in NiCu Dual-Atom Catalysts for CO2 Electroreduction

Dual-atom catalysts (DACs) have become an emerging platform to provide more flexible active sites for electrocatalytic reactions with multi-electron/proton transfer, such as the CO₂  reduction reaction (CRR). However, the introduction of asymmetric dual-atom sites causes complexity in structure, leaving an incomprehensive understanding of the inter-metal interaction and catalytic mechanism. Taking NiCu DACs as an example, herein, a more rational structural model is proposed, and the distance-dependent inter-metal interaction is investigated by combining theoretical simulations and experiments, including density functional theory computation, aberration-corrected transmission electron microscopy, synchrotron-based X-ray absorption fine structure, and Monte Carlo experiments. A distance threshold around 5.3 Å between adjacent NiN₄  and CuN₄  moieties is revealed to trigger effective electronic regulation and boost CRR performance on both selectivity and activity. A universal macro-descriptor rigorously correlating the inter-metal distance and intrinsic material features (e.g., metal loading and thickness) is established to guide the rational design and synthesis of advanced DACs. This study highlights the significance of identifying the inter-metal interaction in DACs, and helps bridge the gap between theoretical study and experimental synthesis of atomically dispersed catalysts with highly correlated active sites.

Stable and Highly Efficient Hydrogen Evolution from Seawater Enabled by an Unsaturated Nickel Surface Nitride

Electrocatalytic production of hydrogen from seawater provides a route to low-cost and clean energy conversion. However, the hydrogen evolution reaction (HER) using seawater is greatly hindered by the lack of active and stable catalysts. Herein, an unsaturated nickel surface nitride (Ni-SN@C) catalyst that is active and stable for the HER in alkaline seawater is prepared. It achieves a low overpotential of 23 mV at a current density of 10 mA cm^-2 in alkaline seawater electrolyte, which is superior to Pt/C. Compared to conventional transition metal nitrides or metal/metal nitride heterostructures, the Ni-SN@C has no detectable bulk nickel nitride phase. Instead, unsaturated NiN bonding on the surface is present. In situ Raman measurements show that the Ni-SN@C performs like Pt with the ability to generate hydronium ions in a high-pH electrolyte. The catalyst operation is then demonstrated in a two-electrode electrolyzer system, coupling with hydrazine oxidation at the anode. Using this system, a cell voltage of only 0.7 V is required to achieve a current density of 1 A cm^-2 .

Barriers to consent taking in ECT

Introduction

There were 16,482 administrations of Electro-convulsive Therapy (ECT) to 2835 individuals in England between January-March 1999. Controversy still surrounds the safety, ethics and necessity of ECT with some patients reporting severe adverse effects and feeling particularly strongly about it being administered without their consent. NICE guidelines along with the ECT accreditation service (ECTAS) sought to address these concerns and raise standards for ECT in UK.

Aims and Objective

To identify any barriers to compliance with NICE guidelines regarding consent for ECT.

Methods

All patients newly started on ECT during a 3 month period at Hellesdon Hospital were enrolled into this study. Case notes were analysed for 16 patients against the 21 standard ECTAS consent criteria.

Results

The hospital rated good (70–89%) or excellent (90–100%) for all guidance except the one which requires patients to complete some sections of the consent form. Only 63% of the patients had completed these, however 100% went on to sign the consent form before every session. Guidance compliance was excellent for 15 (72%) of items examined.

Conclusions

There is good compliance with NICE guideline relating to consent for ECT. The only barrier to full compliance was inadequate documentation by patients in some sections. Steps to improve patient participation can now be implemented. This will provide assurance that ECT is used appropriately and that the process fully enables informed consent. Further research is required to discover the reasons for unsatisfactory patient participation in the consent process.

Immunocytochemistry controls using cell culture

A continuing problem in cytology laboratories is the lack of adequate control material for immunocytochemical testing. Usual control procedures involve testing paraffin-embedded control materials along with the patient specimens. These control materials are fundamentally unlike cytologic preparations. We have developed a method to make control preparations for immunocytochemical analysis using cultured anaplastic cells with known antigenic features from commercial sources. Cell lines included melanoma, rhabdomyosarcoma, T-cell leukemia, and squamous-cell carcinoma. Modified Saccomano and acetone fixation coupled with the cytospin technique enabled good-quality preparations. Cell lines were tested with antibodies for HMB-45, actin, leukocyte common antigen (LCA) and cytokeratin, which avidin-biotin immunoperoxidase and diaminobenzidine (DAB) as chromogens. Our final preparations were easily interpretable with excellent morphologic preservation of cellular detail. Cultured cells provide a superior method for preparing almost unlimited numbers of control slides for immunocytochemistry for laboratories with access to a tissue culture facility.