The need for the development of efficient electrochemical energy storage devices with high energy density, power density and safety is becoming more and more urgent in recent years, and the key for achieving the outst...The need for the development of efficient electrochemical energy storage devices with high energy density, power density and safety is becoming more and more urgent in recent years, and the key for achieving the outstanding performance is the suitable structural designing of active materials. Nanoarray architecture emerged as one of the most promising structures, as it can offer many advantages to boost the electrochemical performance. Specifically, this kind of integrated electrodes can provide a large electrochemically active surface area, faster electron transport and electrolyte ion diffusion, leading to substantially improved capacitive, rate and cycling performances. In this paper, we will review the recent advances in strategies for synthesis of materials with nanoarray architectures and their applications in supercapacitors and batteries.展开更多
The significant positive green environment influence of magnesium alloy usage in transport could be compromised by catastrophic fast fracture caused by stress corrosion cracking(SCC). Transgranular stress corrosion cr...The significant positive green environment influence of magnesium alloy usage in transport could be compromised by catastrophic fast fracture caused by stress corrosion cracking(SCC). Transgranular stress corrosion cracking(TGSCC) of AZ91 was evaluated using the linearly increasing stress test(LIST) and the constant extension rate test(CERT). The TGSCC threshold stress was 55-75 MPa in distilled water and in 5 g/L NaCl. The TGSCC velocity was 7×10-10-5×10-9 m/s. A delayed hydride-cracking(DHC) model for TGSCC was implemented using a finite element script in MATLAB and the model predictions were compared with experiment. A key outcome is that,during steady state TGSCC propagation,a high dynamic hydrogen concentration is expected to build up behind the crack tip. A number of recommendations are given for preventing SCC of Mg alloys in service. One of the most important recommendations might be that the total stress in service(i.e. the stress from the service loading + the fabrication stress + the residual stress) should be below a threshold level,which,in the absence of other data,could be(conservatively) estimated to be about 50% of the tensile yield strength.展开更多
基金financially supported by the National Natural Science Foundation of China (21125101, 21271018)the National Basic Research Program of China (973 Program) (2011CBA00503 and 2011CB932403)+1 种基金the Program for New Century Excellent Talents in Universitiesthe Program for Changjiang Scholars and Innovative Research Team in University
文摘The need for the development of efficient electrochemical energy storage devices with high energy density, power density and safety is becoming more and more urgent in recent years, and the key for achieving the outstanding performance is the suitable structural designing of active materials. Nanoarray architecture emerged as one of the most promising structures, as it can offer many advantages to boost the electrochemical performance. Specifically, this kind of integrated electrodes can provide a large electrochemically active surface area, faster electron transport and electrolyte ion diffusion, leading to substantially improved capacitive, rate and cycling performances. In this paper, we will review the recent advances in strategies for synthesis of materials with nanoarray architectures and their applications in supercapacitors and batteries.
文摘The significant positive green environment influence of magnesium alloy usage in transport could be compromised by catastrophic fast fracture caused by stress corrosion cracking(SCC). Transgranular stress corrosion cracking(TGSCC) of AZ91 was evaluated using the linearly increasing stress test(LIST) and the constant extension rate test(CERT). The TGSCC threshold stress was 55-75 MPa in distilled water and in 5 g/L NaCl. The TGSCC velocity was 7×10-10-5×10-9 m/s. A delayed hydride-cracking(DHC) model for TGSCC was implemented using a finite element script in MATLAB and the model predictions were compared with experiment. A key outcome is that,during steady state TGSCC propagation,a high dynamic hydrogen concentration is expected to build up behind the crack tip. A number of recommendations are given for preventing SCC of Mg alloys in service. One of the most important recommendations might be that the total stress in service(i.e. the stress from the service loading + the fabrication stress + the residual stress) should be below a threshold level,which,in the absence of other data,could be(conservatively) estimated to be about 50% of the tensile yield strength.
