分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-05-02
摘要: In this work, we investigate the influence of oxygen non-stoichiometry on the characteristics of LiNi0.8Co0.1Mn0.1O2 cathode material. Among the investigated samples, the level of Ni/Li disorder in the bulk and the thickness of auto-generated layer on the surface share the same trend as the amount of oxygen loss in LiNi0.8Co0.1Mn0.1O2 materials. It indicates that the aforementioned key structural in- stabilities should be tightly related to the oxygen defects and the induced structural relaxation. As a consequence of structural entirety, the sample with the least defects presents the highest discharge capacity (192.9 mAhg 1 at 0.1C), the best rate capability (160.1 mAhg 1 at 5C), and the most stable cyclibility (89.9% at 200th). Our results demonstrate that oxygen deficiency plays a key role to determine the electrochemical performance of high-nickel cathode materials.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-05-02
摘要: A novel approach is presented in this article to qualitatively and semiquantitatively analyze multiple heavy metal ions simultaneously by a colorimetric array test strip. As a proof-of- concept application, a multi-ion analysis array test strip (for Hg2+, Ag+, and Cu2+) was fabricated through immobilizing five specifically responsive indicators in typical matrixes with tunable sensitivities. The as-obtained test strip shows not only high selectivity for Hg2+, Ag+, and Cu2+, respectively, but also can be applied for their mixtures. The detection limit of the test strip is well below the Chinese wastewater discharge standard concentrations. Moreover, the array test strip demonstrates excellent anti-interference capability, detection, and production reproducibility, long-term storage stability, and real water sample applicability.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-05-02
摘要: A novel layered GGAG/YAG composite scintillation ceramic can be prepared at 1650◦C using an easily accessible preparation procedure. The oxygen sintering-hot isostatic pressing method implemented in this work can significantly shorten the preparation period of scintillation ceramics. The ceramic exhibits regular grain microstructure. Interface of the composite ceramic is clean and straight. As prepared, the layered Ce:GGAG/Cr:YAG composite ceramic can emit a broad range of photons with wavelength from 500 to 750 nm under excitation. The integral spectra is composed of three parts: emitted photons of Cr:YAG and Ce:GGAG and emitted light of Cr:YAG excitated by the photons emitted by the Ce:GGAG ceramic layerprepared by the proposed method. The method accomplished in this work can significantly improve the exploration of full spectrum scintillation/luminescence ceramics preparation and spectra designation.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-05-02
摘要: Planar heterojunction perovskite solar cells were fabricated through a low temperature approach. We find that the device performance significantly depends on the external bias before and during measurements. By appropriate optimization of the bias conditions, we could achieve an 8-fold increase in the power conversion efficiency. The significant improvement in device performance might be caused by the ion motion in the perovskite under the external electric field.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-05-02
摘要: Environmentally benign hybrid interlayers are prepared by modifying the zinc sulfide (ZnS) with phenanthroline/derivatives and utilized in inverted polymer solar cells (PSCs). Performances of the inverted PSCs are improved enormously by incorporating these hybrid inter- layers, as which can effectively improve the energy level alignment, electron mobility, surface morphology, and interfacial contact. Greatly improved power conversion efficiencies (PCEs) of 7.79%, 8.00%, 7.47%, and 7.56% are achieved with these hybrid interlayers ZnS-BCP, ZnS-Bphen, ZnS-Mphen, and ZnS-Phen, respectively, compared to the PCE of 2.99% of the reference ZnS-based device, based on PTB7:PC71BM active layer. Our results demonstrate that hybrid interfacial materials comprising inorganic and organic semiconductor possess promising potential to improve the performance of organic electronic devices, and set an example to develop this novel class of interfacial materials for electronic devices.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-04-06
摘要: Cooperative down-conversion (DC) with emission of two near-infrared photons for each blue photon absorbed was achieved in Tb3+/Yb3+ co-doped yttrium lithium fluoride single crystals grown by an improved Bridgman method. The luminescent properties of the c