The electronic structures of various Cu^(+) luminescence centers in wurtzite ZnS are studied by using first-principles linear muffin-tin-orbital method combining atomic sphere approximation.The results for ZnS:Cu:Cl a...The electronic structures of various Cu^(+) luminescence centers in wurtzite ZnS are studied by using first-principles linear muffin-tin-orbital method combining atomic sphere approximation.The results for ZnS:Cu:Cl and ZnS:Cu:Al show that Cu acceptor states are anomalously deep(beyond 2.7eV above the top of valence band)and located near the bottom of conduction band in these two cases.On the other hand,the results for ZnS:Cu with sulfur vacancies manifest that the Cu+center is an associated center,whose Cu d-like states are situated above the top of valence band.展开更多
以ZnCl_(2)为硬模板和锌源,三聚氰胺和硫脲为氮源和硫源,废弃生物质橘子皮为碳源,通过高温烧结和后续蚀刻处理制备出硫化锌纳米点与三维N-S共掺杂炭纳米片的纳米复合材料(ZnS/NS-CN)。当应用于锂离子电池时,ZnS/NSCN表现出较高的可逆容...以ZnCl_(2)为硬模板和锌源,三聚氰胺和硫脲为氮源和硫源,废弃生物质橘子皮为碳源,通过高温烧结和后续蚀刻处理制备出硫化锌纳米点与三维N-S共掺杂炭纳米片的纳米复合材料(ZnS/NS-CN)。当应用于锂离子电池时,ZnS/NSCN表现出较高的可逆容量(0.1 A g^(−1)下,循环300次后容量仍有853.5 mAh g^(−1)),优异的长期循环稳定性(5 A g^(−1)下,循环1000次后,容量保持率为70.1%)和优异的倍率性能。此外,在0.5~4 V下组装和测试的ZnS/NS-CN//LiNiCoMnO2全电池表现出优异的电池性能(在0.2 C下循环150次后容量为140.4 mAh g^(−1),能量密度为132.4 Wh kg^(−1))。展开更多
文摘The electronic structures of various Cu^(+) luminescence centers in wurtzite ZnS are studied by using first-principles linear muffin-tin-orbital method combining atomic sphere approximation.The results for ZnS:Cu:Cl and ZnS:Cu:Al show that Cu acceptor states are anomalously deep(beyond 2.7eV above the top of valence band)and located near the bottom of conduction band in these two cases.On the other hand,the results for ZnS:Cu with sulfur vacancies manifest that the Cu+center is an associated center,whose Cu d-like states are situated above the top of valence band.
文摘纳米技术研究体系中量子点是重要的研究模块之一,量子点尺寸非常小,具有独特的光物理特性。该文旨通过实验进行分析,实验过程选择99%纯度硼氢化钠、99%纯度硫酸锌、S212恒速搅拌器、TG16-WS高速离心机、0.310 mL巯基乙酸等,制备0.4565 g CdCl_(2)·2.5H_(2)O混合液,当样本溶液呈现橙色时,表明CdTe核已制备完成。实验结果显示:单脉冲能量增加时,τ_(-rise)与τ_(2)有所降低,τ_(1)数值增加,τ_(-rise)与壳层厚度呈正比关系。通过对量子点荧光特性的分析,有利于促进核壳结构量子点的制备。
文摘以ZnCl_(2)为硬模板和锌源,三聚氰胺和硫脲为氮源和硫源,废弃生物质橘子皮为碳源,通过高温烧结和后续蚀刻处理制备出硫化锌纳米点与三维N-S共掺杂炭纳米片的纳米复合材料(ZnS/NS-CN)。当应用于锂离子电池时,ZnS/NSCN表现出较高的可逆容量(0.1 A g^(−1)下,循环300次后容量仍有853.5 mAh g^(−1)),优异的长期循环稳定性(5 A g^(−1)下,循环1000次后,容量保持率为70.1%)和优异的倍率性能。此外,在0.5~4 V下组装和测试的ZnS/NS-CN//LiNiCoMnO2全电池表现出优异的电池性能(在0.2 C下循环150次后容量为140.4 mAh g^(−1),能量密度为132.4 Wh kg^(−1))。