Harbin Engineering University

About: Harbin Engineering University is a education organization based out in Harbin, Heilongjiang, China. It is known for research contribution in the topics: Control theory & Computer science. The organization has 31149 authors who have published 27940 publications receiving 276787 citations. The organization is also known as: HEU.

Hierarchical nickel-cobalt phosphide yolk-shell spheres as highly active and stable bifunctional electrocatalysts for overall water splitting.

Abstract: To improve the efficiency of overall water splitting, highly active and stable bifunctional electrocatalysts are highly desirable. Herein, we fabricated mixed Ni–Co phosphides (Ni1−xCox–P) as bifunctional catalysts for overall water splitting. Structural characterizations indicated that the Ni1−xCox–P catalysts (0 > x > 1) exhibited hierarchical yolk-shelled morphologies, with a total diameter of 1–2 μm. Interestingly, the shell was assembled by numerous nanosheets with a thickness less than 10 nm. The electrochemical measurements indicated that the Ni1−xCox–P catalysts (0 < x < 1) showed significantly enhanced OER and HER activities in comparison to the pure Ni–P and Co–P catalysts, and the highest OER and HER activities were achieved as x = 0.31. To drive a current density of 10 mA cm−2, the Ni0.69Co0.31–P catalyst required an overpotential of 266 mV for OER and 96 mV for HER, respectively. The alkaline water electrolyzer with the Ni0.69Co0.31–P catalysts as the cathode and anode catalysts required a cell voltage of ca. 1.59 V to achieve a current density of 10 mA cm−2, which was comparable to the integrated performance of commercial Pt/C and IrO2. Furthermore, the electrolyzer assembled by the bufictional electrocatalysts showed a more stable performance than one assembled by commercial Pt/C and IrO2 operated at the simialr current density. The superior activity and long-term stability demonstrate that the hierarchical mixed Ni–Co phosphides have promising potential for application in large-scale water splitting.

Deadbeat Dissipative FIR Filtering

Abstract: In this paper, we propose a new deadbeat dissipative filter with a finite impulse response (FIR) structure for linear discrete-time systems with external disturbance; this filter is called a deadbeat dissipative FIR filter (DDFF). The new filter ensures $(Q,S,R)\text{--}\alpha$ -dissipativity and the deadbeat property based on three slack matrix variables. By tuning the weighting parameters provided by the $(Q,S,R)\text{--}\alpha$ -dissipativity in the proposed DDFF, we present $H_{\infty}$ and passive FIR filters in a unified framework and investigate ways of improving the $l_{2}$ stability, bounded-disturbance bounded-error stability, and robustness of FIR filters. The gain matrix of the proposed DDFF is obtained by solving a convex problem using the linear matrix inequality approach. Two numerical examples are provided to demonstrate the effectiveness and advantages of the obtained theoretical results.