Senthilkumar Baskar, Rambabu Angalakurthi, Murugesan Chinnasamy, Krupanidhi Saluru Baba, Barpanda Prabeer
Faraday Materials Laboratory (FaMaL), Materials Research Centre, Indian Institute of Science, C.V. Raman Avenue, Bangalore 560012, India.
Department of Basic Sciences and Humanities, GMR Institute of Technology, Rajam, Andhra Pradesh 532127, India.
ACS Omega. 2020 Mar 24;5(13):7219-7224. doi: 10.1021/acsomega.9b03835. eCollection 2020 Apr 7.
Iron-based polyanionic materials can be exploited to realize low cost, durable, and safe cathodes for both bulk and thin film sodium-ion batteries. Herein, we report pulsed laser deposited mixed phosphate NaFe(PO)PO as a positive electrode for thin film sodium-ion microbatteries. The bulk material and thin films of NaFe(PO)PO are employed by solution combustion synthesis (SCS) and the pulsed laser deposition (PLD) technique, respectively. Phase purity and the nature of the crystallinity of the thin films were confirmed by grazing incidence X-ray diffraction and transmission electron microscopy. Identification of surface roughness and morphology was obtained from atomic force microscopy and scanning electron microscopy, respectively. Emerging electrochemical properties were observed from charge-discharge profiles of the thin films, which are well comparable to bulk material properties. The NaFe(PO)PO thin film electrodes delivered a highly reversible Na storage capacity of ∼120 mAh g with an excellent stability of over 500 cycles. Electrochemical analysis results revealed that the thickness of the film affects the storage capacity.
铁基聚阴离子材料可用于实现用于块状和薄膜钠离子电池的低成本、耐用且安全的阴极。在此，我们报道了脉冲激光沉积的混合磷酸盐NaFe(PO)PO作为薄膜钠离子微型电池的正极。NaFe(PO)PO的块状材料和薄膜分别通过溶液燃烧合成（SCS）和脉冲激光沉积（PLD）技术制备。通过掠入射X射线衍射和透射电子显微镜确认了薄膜的相纯度和结晶性质。分别从原子力显微镜和扫描电子显微镜获得了表面粗糙度和形貌的识别结果。从薄膜的充放电曲线观察到了新出现的电化学性质，其与块状材料的性质具有良好的可比性。NaFe(PO)PO薄膜电极具有约120 mAh g的高度可逆钠存储容量，在超过500次循环中具有出色的稳定性。电化学分析结果表明，薄膜的厚度会影响存储容量。
