Remarkable progress was made in the development of white-light-emitting diodes （LEDs）. White LEDs provided a light element having a semiconductor InGaN light-emitting chip （blue or UV LEDs） and luminescent phospho...Remarkable progress was made in the development of white-light-emitting diodes （LEDs）. White LEDs provided a light element having a semiconductor InGaN light-emitting chip （blue or UV LEDs） and luminescent phosphors. Here we reported the sialon s-phase of （Sr,Eu）2A12Si10N14O4. Eu^2＋ activator ions that were substituted for the strontium site represented a new type of yeUow-green phosphor that could be excited by blue LEDs used for application in the fabrication of white LEDs.展开更多
Vanadium molybdenum oxynitrides nanoparticles were synthesized successfully in the channels of MCM-41 after surface modification,vacumm co-impregnation and nitridation technology.The products were investigated by nitr...Vanadium molybdenum oxynitrides nanoparticles were synthesized successfully in the channels of MCM-41 after surface modification,vacumm co-impregnation and nitridation technology.The products were investigated by nitrogen sorption measurement,X-ray powder diffraction（XRD）,high-resolution transmission electron microscopy（HRTEM）,energy dispersive analysis of X-rays（EDAX）and CNH element analysis.The investigation resnlts show that superfine nanoparticles of vanadium molybderum oxynitrides exist in the channels of MCM-41.展开更多
The development of Li-S batteries(LSBs)is hindered by the low utilization of S species and sluggish redox reaction kinetics.Polar metal oxides always possess high adsorption to polar S species,while conductive metal n...The development of Li-S batteries(LSBs)is hindered by the low utilization of S species and sluggish redox reaction kinetics.Polar metal oxides always possess high adsorption to polar S species,while conductive metal nitrides show fast electron transport and ensure fast redox reaction of S species.The combination merits of metal oxides and metal nitrides in one provide an effective strategy to improve the electrochemical performance of LSBs.In this work,defect design of niobium oxynitrides highly dispersed on graphene(NbON-G)is evaluated as effective trapper and catalyst for S species.Owning to the effective structural merits including enriched active sites,alleviated volume variation,defect modulated electronic property,and in-situ chemisorption and catalytic conversion of soluble lithium polysulfides(LiPSs),the LSBs with NbON-G modified separator show remarkably enhanced performance compared to NbN-G and Nb_(2)O_(5)-G.Surprisingly,even at low temperature of−40°C,the LSBs with NbON-G can operate for 1,000 cycles with 0.04%capacity decay per cycle(Rate:2 C).展开更多
通过无定型磷酸铝在大约800℃的高温下同氨反应,制备了新型催化材料氮化磷酸铝.考察了磷酸铝粒度、氨流量和氮化温度对制备的影响.实验发现材料粒径对氮化有一定的影响,粒径小于0.25 mm时此影响消失.氮化过程需要很大的氨流量,才能保证...通过无定型磷酸铝在大约800℃的高温下同氨反应,制备了新型催化材料氮化磷酸铝.考察了磷酸铝粒度、氨流量和氮化温度对制备的影响.实验发现材料粒径对氮化有一定的影响,粒径小于0.25 mm时此影响消失.氮化过程需要很大的氨流量,才能保证较快的氮化速度.氨流量低时,反应速度太慢,氮化时间很长.氮化速度随着氮化温度的升高而加快.实验还发现800℃下氮化已有明显的磷损失,氮化开始5 h P/Al(原子数比)由1降至0.75左右,然后保持恒定.建立了描述氮化过程中样品的氮含量随氮化时间变化的一级表观动力学方程,该方程能较好的拟合实验数据.展开更多
基金Project supported by the Economic Affair (95-EC-17-A-07-S1-043)the National Science Council (94-2113-M-002-030)
文摘Remarkable progress was made in the development of white-light-emitting diodes （LEDs）. White LEDs provided a light element having a semiconductor InGaN light-emitting chip （blue or UV LEDs） and luminescent phosphors. Here we reported the sialon s-phase of （Sr,Eu）2A12Si10N14O4. Eu^2＋ activator ions that were substituted for the strontium site represented a new type of yeUow-green phosphor that could be excited by blue LEDs used for application in the fabrication of white LEDs.
文摘Vanadium molybdenum oxynitrides nanoparticles were synthesized successfully in the channels of MCM-41 after surface modification,vacumm co-impregnation and nitridation technology.The products were investigated by nitrogen sorption measurement,X-ray powder diffraction（XRD）,high-resolution transmission electron microscopy（HRTEM）,energy dispersive analysis of X-rays（EDAX）and CNH element analysis.The investigation resnlts show that superfine nanoparticles of vanadium molybderum oxynitrides exist in the channels of MCM-41.
基金This research was funded by the National Natural Science Foundation of China(No.52102296)the Guangzhou Municipal Science and Technology Bureau(No.202102020055)+2 种基金the Science and Technology Program of Guangzhou(No.2019050001)Outstanding Youth Project of Guangdong Natural Science Foundation(No.2021B1515020051)Yunnan Expert Workstation(No.202005AF150028).
文摘The development of Li-S batteries(LSBs)is hindered by the low utilization of S species and sluggish redox reaction kinetics.Polar metal oxides always possess high adsorption to polar S species,while conductive metal nitrides show fast electron transport and ensure fast redox reaction of S species.The combination merits of metal oxides and metal nitrides in one provide an effective strategy to improve the electrochemical performance of LSBs.In this work,defect design of niobium oxynitrides highly dispersed on graphene(NbON-G)is evaluated as effective trapper and catalyst for S species.Owning to the effective structural merits including enriched active sites,alleviated volume variation,defect modulated electronic property,and in-situ chemisorption and catalytic conversion of soluble lithium polysulfides(LiPSs),the LSBs with NbON-G modified separator show remarkably enhanced performance compared to NbN-G and Nb_(2)O_(5)-G.Surprisingly,even at low temperature of−40°C,the LSBs with NbON-G can operate for 1,000 cycles with 0.04%capacity decay per cycle(Rate:2 C).
文摘通过无定型磷酸铝在大约800℃的高温下同氨反应,制备了新型催化材料氮化磷酸铝.考察了磷酸铝粒度、氨流量和氮化温度对制备的影响.实验发现材料粒径对氮化有一定的影响,粒径小于0.25 mm时此影响消失.氮化过程需要很大的氨流量,才能保证较快的氮化速度.氨流量低时,反应速度太慢,氮化时间很长.氮化速度随着氮化温度的升高而加快.实验还发现800℃下氮化已有明显的磷损失,氮化开始5 h P/Al(原子数比)由1降至0.75左右,然后保持恒定.建立了描述氮化过程中样品的氮含量随氮化时间变化的一级表观动力学方程,该方程能较好的拟合实验数据.
