High-crystalline Na_1.1V₃O_7.9 nanoplates were synthesized by a facile sol-gel reaction followed by calcination. The microstructure and crystallinity of the nanoplates were primarily determined by calcination temperature. The maximum crystallinity Na_1.1V₃O_7.9 sample was calcined at 500 °C was calculated by XRD, and the DSC demonstrated that the amorphous transformation temperature begins at 550 °C. The XPS spectrum confirmed the presence of Na_1.1V₃O_7.9 and consistent with the XRD test results. The SEM/TEM test illustrated the crystal particle growth of the Na_1.1V₃O_7.9 nanoplates. Electrochemical results showed that the maximum crystallinity Na_1.1V₃O_7.9 sample prepared at 500 °C exhibited the optimum performance when evaluated as a cathode material for lithium-ion batteries: the discharge capacity was maintained at 195 mAh g⁻¹ after 150 cycles at a current of 100 mA g⁻¹.

中文翻译：

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结晶度对Na 1.1 V 3 O 7.9纳米板作为锂离子正极材料的容量和循环稳定性的影响

通过容易的溶胶-凝胶反应然后煅烧合成了高结晶的Na _1.1 V ₃ O _7.9纳米板。纳米板的微观结构和结晶度主要由煅烧温度确定。通过XRD计算在500°C下煅烧的最大结晶度Na _1.1 V ₃ O _7.9样品，DSC证明无定形转变温度始于550°C。XPS光谱证实了Na _1.1 V ₃ O _7.9的存在，并且与XRD测试结果一致。SEM / TEM测试表明Na _1.1 V ₃的晶体颗粒生长O _7.9纳米板。电化学结果表明，在500℃下制备的最大结晶度Na _1.1 V ₃ O _7.9样品作为锂离子电池的正极材料评估时表现出最佳性能：在150次循环中，放电容量保持在195 mAh g ^-1。 100 mA g ^-1的电流。