The current efficiency for NF3 formation was independent on the current density in the range of 200 to 1,000 mA·cm^2. The average values of NF3 current efficiencies on the BDD (boron-doped diamond) anode with t...The current efficiency for NF3 formation was independent on the current density in the range of 200 to 1,000 mA·cm^2. The average values of NF3 current efficiencies on the BDD (boron-doped diamond) anode with the boron-concentration of 2,500 ppm were 32.3% at 80℃, 63.3% at 100℃ and 59.7% at 120℃. The best current efficiencies for NF3 formation on the BDD anode with boron-concentrations of 2,500, 5,000 and 7,500 ppm were obtained at 100℃ and those were 63.3%, 73.3% and 56.2%, respectively. Although anode effect occurred on the BDD electrodes covered with a part of the surface of the spiculate structure, which had the boron-concentrations higher than 7,500 ppm, it did not take place on the BDD electrodes covered with the surface of diamond structure, even if the BDD electrode had the boron-concentration of 8,000 ppm.展开更多
Neutral Zn-air batteries(ZABs) have attracted much attention due to the enhanced lifespan and stability.However, their development is suppressed by the poor catalytic properties of the air-electrocatalysts for oxygen ...Neutral Zn-air batteries(ZABs) have attracted much attention due to the enhanced lifespan and stability.However, their development is suppressed by the poor catalytic properties of the air-electrocatalysts for oxygen reduction reaction(ORR) and oxygen evolution reaction(OER). Hence,the exploration of highly efficient electrocatalysts for neutral ZABs is critical. Herein, we designed an economical heterostructure of Pt nanoparticle-modified Zn nanoplates(Pt/Zn NPs). Compared with commercial Pt/C electrocatalyst, our Pt/Zn heterostructure exhibits comparable catalytic properties and ultrahigh stability in neutral media. The heterostructure can reduce the dosage of Pt and offer sufficient active sites,resulting in enhanced catalytic properties for ORR/OER in neutral media. When applied to neutral ZABs as air cathode,our heterostructure exhibits a high power density of 45 mW cm^(-2) and excellent stability of more than 850 cycles with negligible decay, making it the most efficient and robust one in neutral electrolyte. This approach opens a new avenue to strategically design catalysts with high activity for neutral ZABs, rendering them potential in portable and wearable electronic devices.展开更多
Developing highly efficient,cost-effective,and stable electrocatalysts for hydrogen evolution reaction(HER)is of considerable importance but remains challenging.Herein,we report the fabrication of a robust Ru-based el...Developing highly efficient,cost-effective,and stable electrocatalysts for hydrogen evolution reaction(HER)is of considerable importance but remains challenging.Herein,we report the fabrication of a robust Ru-based electrocatalyst,which comprises heterostructured Ru-Ru_(2)P nanoparticles that are embedded in the N,P-codoped carbon nanofibers(CNFs),through a synthetic strategy involving electrospinning and temperature-controlled pyrolysis treatment.The as-prepared Ru-Ru_(2)P catalyst(Ru-Ru_(2)P@CNFs)shows excellent HER catalytic activities with low overpotentials of 11 and 14 mV in acidic and alkaline media,respectively,to achieve a current density of 10 mA cm^(−2),which are superior to the individual components of pure Ru and Ru_(2)P catalysts.Density functional theory calculations demonstrate the existence of electronic coupling effect between Ru and Ru_(2)P at the heterointerfaces,leading to a well-modulated electronic structure with optimized hydrogen adsorption strength and enhanced electrical conductivity for efficient HER electrocatalysis.In addition,the overall synthetic strategy can be generalized for the synthesis of a series of transitional metal phosphide-based nanofibers,thereby holding a remarkable capacity for various potential applications.展开更多
文摘The current efficiency for NF3 formation was independent on the current density in the range of 200 to 1,000 mA·cm^2. The average values of NF3 current efficiencies on the BDD (boron-doped diamond) anode with the boron-concentration of 2,500 ppm were 32.3% at 80℃, 63.3% at 100℃ and 59.7% at 120℃. The best current efficiencies for NF3 formation on the BDD anode with boron-concentrations of 2,500, 5,000 and 7,500 ppm were obtained at 100℃ and those were 63.3%, 73.3% and 56.2%, respectively. Although anode effect occurred on the BDD electrodes covered with a part of the surface of the spiculate structure, which had the boron-concentrations higher than 7,500 ppm, it did not take place on the BDD electrodes covered with the surface of diamond structure, even if the BDD electrode had the boron-concentration of 8,000 ppm.
基金financially supported by the National Natural Science Foundation of China (21706090 and 51772135)the Ministry of Education of China (6141A02022516)+3 种基金the Natural Science Foundation of Guangdong Province (2014A030306010)Jinan University (88016105)the Natural Science Foundation of Guangzhou (201904010049)the Fundamental Research Foundation for the Central Universities (21617326)。
文摘Neutral Zn-air batteries(ZABs) have attracted much attention due to the enhanced lifespan and stability.However, their development is suppressed by the poor catalytic properties of the air-electrocatalysts for oxygen reduction reaction(ORR) and oxygen evolution reaction(OER). Hence,the exploration of highly efficient electrocatalysts for neutral ZABs is critical. Herein, we designed an economical heterostructure of Pt nanoparticle-modified Zn nanoplates(Pt/Zn NPs). Compared with commercial Pt/C electrocatalyst, our Pt/Zn heterostructure exhibits comparable catalytic properties and ultrahigh stability in neutral media. The heterostructure can reduce the dosage of Pt and offer sufficient active sites,resulting in enhanced catalytic properties for ORR/OER in neutral media. When applied to neutral ZABs as air cathode,our heterostructure exhibits a high power density of 45 mW cm^(-2) and excellent stability of more than 850 cycles with negligible decay, making it the most efficient and robust one in neutral electrolyte. This approach opens a new avenue to strategically design catalysts with high activity for neutral ZABs, rendering them potential in portable and wearable electronic devices.
基金financially supported by the Natural Science Foundation of Zhejiang Province (LQ20B030001 and LY20E020002)China Postdoctoral Science Foundation (2021M702305)。
文摘Developing highly efficient,cost-effective,and stable electrocatalysts for hydrogen evolution reaction(HER)is of considerable importance but remains challenging.Herein,we report the fabrication of a robust Ru-based electrocatalyst,which comprises heterostructured Ru-Ru_(2)P nanoparticles that are embedded in the N,P-codoped carbon nanofibers(CNFs),through a synthetic strategy involving electrospinning and temperature-controlled pyrolysis treatment.The as-prepared Ru-Ru_(2)P catalyst(Ru-Ru_(2)P@CNFs)shows excellent HER catalytic activities with low overpotentials of 11 and 14 mV in acidic and alkaline media,respectively,to achieve a current density of 10 mA cm^(−2),which are superior to the individual components of pure Ru and Ru_(2)P catalysts.Density functional theory calculations demonstrate the existence of electronic coupling effect between Ru and Ru_(2)P at the heterointerfaces,leading to a well-modulated electronic structure with optimized hydrogen adsorption strength and enhanced electrical conductivity for efficient HER electrocatalysis.In addition,the overall synthetic strategy can be generalized for the synthesis of a series of transitional metal phosphide-based nanofibers,thereby holding a remarkable capacity for various potential applications.