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Rational design and fabrication of efficient and low-cost catalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are crucial for hydrogen production from water electrolysis. Herein, we report heteroatom Fe-incorporated Ni

S leaching induces rapid self-reconstruction and the ready formation of Ni4+ in an Fe–NiSOH electrode, supporting high-efficiency and stable alkaline large-current-density water/seawater oxidation.

A novel electrochemical reconstruction strategy enables the best seawater electrolysis performance.

The electrochemical reduction of CO2 to hydrocarbons involves a multistep proton-coupled electron transfer (PCET) reaction. Second coordination sphere engineering is reported to be effective in the PCET process; however, little is known about the actual catalytic active sites under realistic operating conditions. We have designed a defect-containing metal-organic framework, HKUST-1, through a facile "atomized trimesic acid" strategy, in which Cu atoms are modified by unsaturated carboxylate ligands, producing coordinatively unsaturated Cu paddle wheel (CU-CPW) clusters. We investigate the dynamic behavior of the CU-CPW during electrochemical reconstruction through the comprehensive analysis of in situ characterization results. It is demonstrated that Cu2 (HCOO)3 is maintained after electrochemical reconstruction and that is behaves as an active site. Mechanistic studies reveal that CU-CPW accelerates the proton-coupled multi-electron transfer (PCMET) reaction, resulting in a deep CO2 reduction reaction.

The electrochemical reduction of CO

Coordinatively unsaturated metal sites in metal–organic frameworks (MOFs) hold promises for improving activity and selectivity of catalyst. As the building unit of many MOFs, copper paddle-wheel (CPW) is of great interest to function as activity sites for CO2 reduction due to the ability of copper cations to attract and activate CO2 molecules. However, little is known about the real structure of these active sites for their dynamic structural changes under realistic operating conditions. Here, we apply to design defect metal−organic framework HKUST-1 with coordinatively unsaturated copper paddle wheel through a facile “atomized trimesic acid” strategy, reveal its dynamic behaviour during electrochemical reconstruction and prove its superior CO2 reduction activity. Through comprehensive analysis of various in situ spectroscopy characterizations, it is demonstrated that unsaturated copper paddle wheel clusters [CU-CPWC, Cu2(HCOO)3] are finally formed during electrochemical reconstruction and act as the real active sites. Mechanistic studies based on density functional theory calculations reveal that the higher d band center in CU-CPWC compared with that in CPW accelerates the electron transport from copper atoms to CO2 molecules, which can be exploited to improve the CO2 reduction performance.

Achieving efficient and durable nonprecious hydrogen evolution reaction (HER) catalysts for scaling up alkaline water/seawater electrolysis is desirable but remains a significant challenge. Here, a heterogeneous Ni-MoN catalyst consisting of Ni and MoN nanoparticles on amorphous MoN nanorods that can sustain large-current-density HER with outstanding performance is demonstrated. The hierarchical nanorod-nanoparticle structure, along with a large surface area and multidimensional boundaries/defects endows the catalyst with abundant active sites. The hydrophilic surface helps to achieve accelerated gas-release capabilities and is effective in preventing catalyst degradation during water electrolysis. Theoretical calculations further prove that the combination of Ni and MoN effectively modulates the electron redistribution at their interface and promotes the sluggish water-dissociation kinetics at the Mo sites. Consequently, this Ni-MoN catalyst requires low overpotentials of 61 and 136 mV to drive current densities of 100 and 1000 mA cm

Based on the Novachip ultra-thin layer project in the expressway, the material characteristics, mixture design and road performance of Novachip asphalt mixture are introduced. The application effect of Novachip ultra-thin layer was observed. The results show that Novachip ultra-thin layer has no obvious effect on improving the smoothness of the original road surface. Novachip ultra-thin layer has obvious effect on improving the rutting, and has a good anti-skid performance.

Among various studied catalysts, copper-based electrocatalysts can convert CO2 into hydrocarbons. Two main challenges in this research area are low selectivity, especially for value-added C2+ products and the high overpotentials required to initiate carbon dioxide reduction reaction (CO2RR). The interaction between copper and oxygen has always been inevitable in the design of copper-based catalysts owing to the intrinsic activity of copper and the oxygen-rich environment we live in. Recently, due to the unprecedented development of in-situ characterization, continuously increasing attention has been paid to oxygen species, which is usually accounting for the highest proportion of metalloid composition in copper-based catalysts. Herein, we have summarized the research progress on oxygen-containing copper catalysts, both experimentally and theoretically, and revealed the evolution of oxygen and the relationship between catalytic performance and oxygen species. It is found that the existence of subsurface oxygen in the electrochemical interface of copper-based electrodes has been proved both by in-situ characterization and theoretical simulation, which is also essential for efficient CO2RR to C2+ products. Additionally, selectivity to C2+ products is basically boosted in three ways: facilitating the conversion of CO2 from physical adsorption to chemical adsorption, strengthening intermediate binding and optimizing the adsorption configuration of CO2. It is expected that this review will provide clue for utilizing oxygen to enhance C2+ selectivity in the design of copper-based catalysts.

Developing a facile strategy for universal synthesis of transition metal catalysts is significant to catalytic reactions but remains challenging. Herein, we report an ultrafast one-step electrodeposition method to prepare a series of transition metal foams within one minute for electrocatalytic water splitting. The porous metal foams not only possess unique 3D channels for rapid electrolyte diffusion and gas releasing, but also have robust integrated structures with enhanced conductivity for efficient charge transport. Consequently, the NiCo and NiFe foams only require 86 and 206 mV to output 10 mA cm−2 for hydrogen and oxygen evolution reactions (HER and OER) in 1 M KOH, respectively. Combining the two electrocatalysts, we have assembled an outstanding alkaline electrolyzer, requiring only 1.52 and 1.64 V to deliver 10 and 100 mA cm−2 respectively, outperforming the RuO2(+)//Pt/C(-) electrolyzer. Our study offers an ultrafast and general approach to fabricate 3D porous electrocatalysts for high-performance water splitting.

Tumor biomarkers can serve as tools for early detection, diagnosis, prognosis, therapeutic target, response predicting, therapy monitoring of tumors or can be used as surrogate endpoints. Their abilities to assist various clinical decisions make them indispensable tools for current oncotherapies. Therefore, in the past decades, significant effort has been put into finding sensitive, specific, noninvasive, inexpensive, and clinically feasible tumor biomarkers. This review will summarize the recent progress made in different kinds of tumor biomarkers, introduce a promising and versatile novel tumor biomarker called DEK oncoprotein, and lastly, discuss the prospects of tumor biomarkers.