Although significant progress has been made in many aspects of the emerging aprotic Li-O2 battery system, an indepth understanding of the oxygen reactions is still underway. The oxygen reactions occurring in the posit...Although significant progress has been made in many aspects of the emerging aprotic Li-O2 battery system, an indepth understanding of the oxygen reactions is still underway. The oxygen reactions occurring in the positive electrode distinguish Li-O2 batteries from the conventional Li-ion cells and play a crucial role in the Li-O2 cell＇s performance （capacity, rate capability, and cycle life）. Recent advances in fundamental studies of oxygen reactions in aprotic Li-O2 batteries are reviewed, including the reaction route, kinetics, morphological evolution of Li2O2, and charge transport within Li2O2. Prospects are also provided for future fundamental investigations of Li-O2 chemistry.展开更多
Metal–organic frameworks(MOFs) are of great interest as potential electrochemically active materials.However, few studies have been conducted into understanding whether control of the shape and components of MOFs can...Metal–organic frameworks(MOFs) are of great interest as potential electrochemically active materials.However, few studies have been conducted into understanding whether control of the shape and components of MOFs can optimize their electrochemical performances due to the rational realization of their shapes. Component control of MOFs remains a significant challenge. Herein, we demonstrate a solvothermal method to realize nanostructure engineering of 2D nanoflake MOFs. The hollow structures withNi/Co-and Ni-MOF(denoted as Ni/Co-MOF nanoflakes and Ni-MOF nanoflakes) were assembled for their electrochemical performance optimizations in supercapacitors and in the oxygen reduction reaction(ORR). As a result, the Ni/CoMOF nanoflakes exhibited remarkably enhanced performance with a specific capacitance of 530.4 F g^(-1)at 0.5 A g^(-1)in1 M LiO H aqueous solution, much higher than that of NiMOF(306.8 F g^(-1)) and ZIF-67(168.3 F g^(-1)), a good rate capability, and a robust cycling performance with no capacity fading after 2000 cycles. Ni/Co-MOF nanoflakes also showed improved electrocatalytic performance for the ORR compared to Ni-MOF and ZIF-67. The present work highlights the significant role of tuning 2D nanoflake ensembles of Ni/Co-MOF in accelerating electron and charge transportation for optimizing energy storage and conversion devices.展开更多
The aluminum-air battery is considered to be an attractive candidate as a power source for electric vehicles(EVs) because of its high theoretical energy density(8100 Wh kg^(-1)), which is significantly greater than th...The aluminum-air battery is considered to be an attractive candidate as a power source for electric vehicles(EVs) because of its high theoretical energy density(8100 Wh kg^(-1)), which is significantly greater than that of the state-of-the-art lithium-ion batteries(LIBs). However,some technical and scientific problems preventing the large-scale development of Al-air batteries have not yet to be resolved. In this review, we present the fundamentals, challenges and the recent advances in Al-air battery technology from aluminum anode, air cathode and electrocatalysts to electrolytes and inhibitors. Firstly, the alloying of aluminum with transition metal elements is reviewed and shown to reduce the selfcorrosion of Al and improve battery performance. Additionally for the cathode, extensive studies of electrocatalytic materials for oxygen reduction/evolution including Pt and Pt alloys, nonprecious metal catalysts, and carbonaceous materials at the air cathode are highlighted.Moreover, for the electrolyte, the application of aqueous and nonaqueous electrolytes in Al-air batteries are discussed. Meanwhile, the addition of inhibitors to the electrolyte to enhance electrochemical performance is also explored. Finally, the challenges and future research directions are proposed for the further development of Al-air batteries.展开更多
Electrocatalysts with high catalytic activity and stability play a key role in promising renewable energy technologies, such as fuel cells and metal-air batteries. Here, we report the synthesis of Fe/Fe203 nanoparticl...Electrocatalysts with high catalytic activity and stability play a key role in promising renewable energy technologies, such as fuel cells and metal-air batteries. Here, we report the synthesis of Fe/Fe203 nanoparticles anchored on Fe-N-doped carbon nanosheets （Fe/Fe2Og@Fe-N-C） using shrimp shell-derived N-doped carbon nanodots as carbon and nitrogen sources in the presence of FeCI3 by a simple pyrolysis approach. Fe/Fe203@Fe-N-C obtained at a pyrolysis temperature of 1,000 ℃ （Fe/Fe2OB@Fe-N-C-1000） possessed a mesoporous structure and high surface area of 747.3 m2-g-1. As an electrocatalyst, Fe/Fe203@Fe-N-C-1000 exhibited bifunctional electrocatalytic activities toward the oxygen reduction reaction （ORR） and oxygen evolution reaction （OER） in alkaline media, com- parable to that of commercial Pt/C for ORR and RuO2 for OER, respectively. The Zn-air battery test demonstrated that Fe/Fe2OB@Fe-N-C-1000 had a superior rechargeable performance and cycling stability as an air cathode material with an open drcuit voltage of 1.47 V （vs. Ag/AgCl） and a power density of 193 mW.cm-2 at a current density of 220 mA-cm-2. These performances were better than other commercial catalysts with an open circuit voltage of 1.36 V and a power density of 173 mW-cm^-2 at a current density of 220 mA.cm-2 （a mixture of commercial Pt/C and RuO2 with a mass ratio of 1：1 was used for the rechargeable Zn-air battery measurements）. This work will be helpful to design and develop low-cost and abundant bifunctional oxygen electrocatalysts for future metal-air batteries.展开更多
基金supported by the Recruitment Program of Global Youth Experts of Chinathe Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA09010401)+1 种基金the Science and Technology Development Program of Jilin Province,China(Grant No.20150623002TC)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20131139)
文摘Although significant progress has been made in many aspects of the emerging aprotic Li-O2 battery system, an indepth understanding of the oxygen reactions is still underway. The oxygen reactions occurring in the positive electrode distinguish Li-O2 batteries from the conventional Li-ion cells and play a crucial role in the Li-O2 cell＇s performance （capacity, rate capability, and cycle life）. Recent advances in fundamental studies of oxygen reactions in aprotic Li-O2 batteries are reviewed, including the reaction route, kinetics, morphological evolution of Li2O2, and charge transport within Li2O2. Prospects are also provided for future fundamental investigations of Li-O2 chemistry.
基金supported by the National Natural Science Foundation of China (Nos. 21571157, U1604123, and 51473149)Outstanding Young Talent Research Fund of Zhengzhou University (1521320001)+1 种基金the Open Project Foundation of Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) (2017–29),Nankai UniversityOpen Project Foundation of Key Laboratory of Inorganic Synthesis and Preparation of Jilin University
文摘Metal–organic frameworks(MOFs) are of great interest as potential electrochemically active materials.However, few studies have been conducted into understanding whether control of the shape and components of MOFs can optimize their electrochemical performances due to the rational realization of their shapes. Component control of MOFs remains a significant challenge. Herein, we demonstrate a solvothermal method to realize nanostructure engineering of 2D nanoflake MOFs. The hollow structures withNi/Co-and Ni-MOF(denoted as Ni/Co-MOF nanoflakes and Ni-MOF nanoflakes) were assembled for their electrochemical performance optimizations in supercapacitors and in the oxygen reduction reaction(ORR). As a result, the Ni/CoMOF nanoflakes exhibited remarkably enhanced performance with a specific capacitance of 530.4 F g^(-1)at 0.5 A g^(-1)in1 M LiO H aqueous solution, much higher than that of NiMOF(306.8 F g^(-1)) and ZIF-67(168.3 F g^(-1)), a good rate capability, and a robust cycling performance with no capacity fading after 2000 cycles. Ni/Co-MOF nanoflakes also showed improved electrocatalytic performance for the ORR compared to Ni-MOF and ZIF-67. The present work highlights the significant role of tuning 2D nanoflake ensembles of Ni/Co-MOF in accelerating electron and charge transportation for optimizing energy storage and conversion devices.
基金supported by Natural Sciences and Engineering Research Council of Canada (NSERC)Canada Research Chair (CRC) Program+1 种基金National Nature Science Foundation of China (No.51474255)Open-End Fund for the Graduate Student Research Innovation Project of Hunan Province (No. 150140008)
文摘The aluminum-air battery is considered to be an attractive candidate as a power source for electric vehicles(EVs) because of its high theoretical energy density(8100 Wh kg^(-1)), which is significantly greater than that of the state-of-the-art lithium-ion batteries(LIBs). However,some technical and scientific problems preventing the large-scale development of Al-air batteries have not yet to be resolved. In this review, we present the fundamentals, challenges and the recent advances in Al-air battery technology from aluminum anode, air cathode and electrocatalysts to electrolytes and inhibitors. Firstly, the alloying of aluminum with transition metal elements is reviewed and shown to reduce the selfcorrosion of Al and improve battery performance. Additionally for the cathode, extensive studies of electrocatalytic materials for oxygen reduction/evolution including Pt and Pt alloys, nonprecious metal catalysts, and carbonaceous materials at the air cathode are highlighted.Moreover, for the electrolyte, the application of aqueous and nonaqueous electrolytes in Al-air batteries are discussed. Meanwhile, the addition of inhibitors to the electrolyte to enhance electrochemical performance is also explored. Finally, the challenges and future research directions are proposed for the further development of Al-air batteries.
基金This work was financially supported by the National Natural Science Foundation of China （Nos. 51372248 and 51432009）, the Instrument Developing Project of the Chinese Academy of Sciences （No. yz201421） and the CAS/SAFEA International Partnership Program for Creative Research Teams of Chinese Academy of Sciences, the CAS Pioneer Hundred Talents Program and the Users with Potential Program （No. 2015HSC- UP006, Hefei Science Center, CAS）, China.
文摘Electrocatalysts with high catalytic activity and stability play a key role in promising renewable energy technologies, such as fuel cells and metal-air batteries. Here, we report the synthesis of Fe/Fe203 nanoparticles anchored on Fe-N-doped carbon nanosheets （Fe/Fe2Og@Fe-N-C） using shrimp shell-derived N-doped carbon nanodots as carbon and nitrogen sources in the presence of FeCI3 by a simple pyrolysis approach. Fe/Fe203@Fe-N-C obtained at a pyrolysis temperature of 1,000 ℃ （Fe/Fe2OB@Fe-N-C-1000） possessed a mesoporous structure and high surface area of 747.3 m2-g-1. As an electrocatalyst, Fe/Fe203@Fe-N-C-1000 exhibited bifunctional electrocatalytic activities toward the oxygen reduction reaction （ORR） and oxygen evolution reaction （OER） in alkaline media, com- parable to that of commercial Pt/C for ORR and RuO2 for OER, respectively. The Zn-air battery test demonstrated that Fe/Fe2OB@Fe-N-C-1000 had a superior rechargeable performance and cycling stability as an air cathode material with an open drcuit voltage of 1.47 V （vs. Ag/AgCl） and a power density of 193 mW.cm-2 at a current density of 220 mA-cm-2. These performances were better than other commercial catalysts with an open circuit voltage of 1.36 V and a power density of 173 mW-cm^-2 at a current density of 220 mA.cm-2 （a mixture of commercial Pt/C and RuO2 with a mass ratio of 1：1 was used for the rechargeable Zn-air battery measurements）. This work will be helpful to design and develop low-cost and abundant bifunctional oxygen electrocatalysts for future metal-air batteries.
