Photoluminenscence property of ferromagnetic ZnMnO thin films

High quality Mn doped ZnO thin films were grown on c-plane Al₂O₃ by oxygen plasma assisted molecular beam epitaxy. Photoluminescence spectra were investigated on the ferromagnetic ZnMnO films. An additional emission located at ∼3.32 eV was observed on these ferromagnetic films for both as-grown and oxygen-annealed samples. It is assigned to the recombination of neutral acceptor bound excitons. The ionization energy of the acceptor was estimated to be 53–80 meV. The observed ferromagnetism was explained to relate with acceptor-type defects.     

铝掺杂ZnMnO纳米晶体的载流子调控铁磁性

通过溶胶-凝胶自燃烧技术合成了Zn_0.95-xAl_xMn_0.05O(x=0、0.03、0.05和0.07)稀磁半导体材料. 并且研究了Al掺杂对Zn_0.95-xAl_xMn_0.05O结构、电学和磁学性质的效果. X射线衍射显示合成的组合物为单相六方晶系纤锌矿型晶体结构,类似于氧化锌.显微图像显示颗粒呈团簇状,但一些单个颗粒呈现六角形纹理. 观察到的电阻率随温度升高(达450 oC)而降低,显示为半导体行为特征.所有组合物具有室温铁磁行为. 饱和磁化强度的值随着Al(载流子)浓度的增加而增加.     

Carriers-assisted Enhanced Ferromagnetism in Al-doped ZnMnO Nano-crystallites

Zn_0.95-xAl_xMn_0.05O (x=0, 0.03, 0.05, and 0.07) dilute magnetic semiconductor materials have been synthesized by sol-gel auto-combustion technique. The effect of Al doping on the structural, electrical, and magnetic properties has been investigated. X-ray diffraction studies demonstrate the existence of single phase characteristic hexagonal wurtzite type crystal structure, similar to the host ZnO, in all the synthesized compositions. Although, the microscopic images revealed that the grains were clustered, yet some individual grains could be seen to have hexagonal texture. Electrical resistivity was observed to decrease with the rise of temperature up to 450 oC, depicting the characteristic semiconductor behavior. Room temperature ferromagnetic behavior was observed in all the compositions. The value of saturation magnetization increased with the increase of Al concentration in ZnMnO system referred to the gradual enhancement of free carriers.     

基于离子注入技术的ZnMnO半导体材料的制备及光谱表征

通过离子注入技术制备了ZnMnO半导体材料，研究离子注入剂量与退火对材料光谱性质的影 响.Raman光谱研究发现，575cm^-1处声子模展宽是由高剂量Mn注入引起的缺陷所 致，退火样品528cm^-1振动模来自Mn相关的杂质振动.室温光致发光谱表明，退 火对高剂量注入样品的可见发光带有增强作用. 关键词： ZnMnO 离子注入 Raman光谱 室温光致发光     

Scalable Synthesis of One-Dimensional Mesoporous ZnMnO3 Nanorods with Ultra-Stable and High Rate Capability for Efficient Lithium Storage

The cost-efficient ZnMnO₃ has attracted increasing attention as a prospective anode candidate for advanced lithium-ion batteries (LIBs) owing to its resourceful abundance, large lithium storage capacity and low operating voltage. However, its practical application is still seriously limited by the modest cycling and rate performances. Herein, a facile design to scalable synthesize unique one-dimensional (1D) mesoporous ZnMnO₃ nanorods (ZMO-NRs) composed of nanoscale particles (≈11 nm) is reported. The 1D mesoporous structure and nanoscale building blocks of the ZMO-NRs effectively promote the transport of ions/electrons, accommodate severe volume changes, and expose more active sites for lithium storage. Benefiting from these appealing structural merits, the obtained ZMO-NRs anode exhibits excellent rate behavior (≈454 mAh g⁻¹ at 2 A g⁻¹) and ultra-long term cyclic performance (≈949.7 mAh g⁻¹ even over 500 cycles at 0.5 A g⁻¹) for efficient lithium storage. Additionally, the LiNi_0.8Co_0.1Mn_0.1O₂//ZMO-NRs full cell presents a practical energy density (≈192.2 Wh kg⁻¹) and impressive cyclability with approximately 91 % capacity retention over 110 cycles. This highlights that the ZMO-NRs product is a highly promising high-rate and stable electrode candidate towards advanced LIBs in electronic devices and sustainable energy storage applications.