Anion-cation dual doping: An effective electronic modulation strategy of Ni2P for high-performance oxygen evolution

Developing of high-performance and low-cost electrocatalysts is of great significance to reduce the overpotential and accelerated the reaction rate of oxygen evolution in water splitting and related energy conversion applications.Herein,Fe,O-dual doped Ni2P(Fe,O-Ni2P)nanoarray is successfully synthesized on carbon cloth demonstrating enhanced electrocatalytic activity and stability for oxygen evolution reaction(OER)under alkaline media.The as-synthesized Fe,O-Ni2P nanoarray exhibits obviously improved OER performance with a low overpotential of 210 mV at 10 mA cm^-2 current density and a Tafel slope of48 mV dec^-1,as well as long-term durability.The strong coupling interaction induced changes in electronic structure lead to relatively higher oxidation state and stronger oxidation ability of the Fe,O-Ni2P nanoarray,together with the high electrochemical surface area and good conductivity contribute to the superior OER performance.This work highlights the anion-cation dual doping strategy may be an effective method for fabrication of catalysts relating to energy conversion applications.

Time-delay identification for linear controlled systems

A new approach for time-delay identification is proposed in linear controlled systems. The delay is derived from the control loop in the system. The frequency-response function of the system is presented in terms of the impedance matrix. It is proved that the inverse form of the function may be expressed in the harmonic function, which is used to fit those data from the experiment. As an example, an isolator with the delayed feedback control is schemed to acquire such data. Using least square algorithm yields that the identified delay can reach any required accuracy.

Controllable selective anchoring of subnanometric Ru clusters or single-atoms/clusters on tungsten nitride for the hydrogen oxidation

The impregnation method in the preparation of metal cluster catalysts typically inadvertently introduces single atoms(SAs) into the substrate. However, the question of whether the introduction of SAs will further improve the catalytic activity of cluster systems for specific reactions such as the hydrogen oxidation reaction(HOR) remains unraveled. Herein, we demonstrate Ru clusters anchored on WN nanowires(RuC/WN) show a higher alkaline HOR catalytic activity in comparison with Ru SAs and nanoclusters(NCs)-coupled catalyst anchored on WN nanowires system(RuC,S/WN). Notably, the RuC/WN exhibits superb intrinsic catalytic activity with a mass-normalized exchange current density of 890 m A mg^(-1)PGM, which is among the top level of well developed Ru-based HOR catalysts. Both theoretical simulation and experimental investigation suggest that RuC/WN owns an optimized H^(*)and OH^(*) reaction intermediates for the alkaline HOR, therefore resulting in the excellent intrinsic HOR catalytic performance.

In-situ template etching synthesis of BiON/BiOCl_(0.9)I_(0.1) heterojunction for photocatalytic degradation of tetracycline

Hierarchical heterostructures have emerged as promising candidates for the efficient photocatalytic degradation of antibiotics owing to their matched energy levels and tunable absorption bands.Herein,we report the facile synthesis of a heterojunction photocatalyst composed of basic bismuth nitrate(BiON)and BiOCl_(0.9)I_(0.1) using a simple room-temperature hydrolysis method.Our results demonstrate that the BiON/BiOCl_(0.9)I_(0.1) composite exhibits superior photodegradation performance compared to pure-phase materials owing to the catalytic enhancement at the heterointerface and the effective separation of the photogenerated carriers.Moreover,the unique three-dimensional microsphere morphology of the synthesized composite enhances its specific surface area and light absorption,further enhancing its photocatalytic activity.In the tetracycline(TC)photodegradation reaction as a model reaction,the catalyst could degrade 88%of TC in just 25 min.Overall,this work provides a promising strategy for the facile and low-cost synthesis of heterogeneous photocatalytic degradation materials.