Structural changes upon lithium insertion in Ni 0.5 TiOPO 4

Abstract

a b s t r a c tNickel titanium oxyphosphate Ni 0.5 TiOPO 4 (NTP), was prepared by co-precipitation route. Its structure was determined by single crystal X-ray diffraction. The compound crystallizes in the monoclinic system, S.G: P2 1 /c [a = 7.333(1)Å, b = 7.316(2)Å, c = 7.339(2)Å,ˇ= 119.62(3) • , Z = 4, R 1 = 0.0142, wR 2 = 0.0429]. The structure might be described as a {TiOPO 4 } framework made of corner-sharing [TiO 6 ] octahedra chains running parallel to [0 0 1] and cross linked by phosphate [PO 4 ] tetrahedral, where half of octahedral cavities created are occupied by Ni atoms, and the other half of octahedral sites are vacant. During the first discharge, the NTP electrode delivered a capacity of 530 mAh/g, upon cycling within 0.5-4 V. To understand the electrochemical reaction mechanism using different characterization techniques viz. in situ synchrotron diffraction. Reciprocal magnetic susceptibility ( −1 ) of NTP, between 4 and 300 K, shows an almost linear behavior and can be fitted by the simple Curie-Weiss law.

Charge/discharge Behavior of Triclinic LiTiOPO₄ Anode Materials for Lithium Secondary Batteries

“…On the other hand, the active materials after the 1st charge were changed into orthorhombic compound. The electrode surfaces after the 1st discharge were assigned to triclinic LiTiOPO 4 . The results were the same after the 10th charge and 10th discharge.…”

“…1 On the other hand, Ti-based MB 0.5 TiOPO 4 (MB = Fe, Co, Ni, or Cu) materials have been researched and developed as high-capacity anode materials for lithium secondary batteries. [2][3][4][5][6][7][8][9] Y. Kee and coworkers reported the synthesis of rhombohedral LiTi 2 (PO 4 ) 3 and orthorhombic Li 1.5 Ti 2 (PO 4 ) 3 via the sol-gel method and the investigation of their use as anode materials for rechargeable Liion batteries. 10 S. Patoux and C. Masquelir reported that LiTiPO 5 / Super P carbon (SP carbon; MMM Carbon, Belgium) electrodes worked as active materials using cyclic voltammetry (CV) measurements and galvanostatic intermittent titration techniques (GITT).…”

In situ anodization of aluminum surfaces studied by x-ray reflectivity and electrochemical impedance spectroscopy

“…17 In contrast to electron based techniques hard x-ray scattering techniques such as x-ray diffraction (XRD) and x-ray reflectivity (XRR) are only slightly affected by gases or liquid. A number of studies applying x-ray scattering techniques to study catalytic 18,19 or electrochemical 20,21 systems under realistic or semi-realistic conditions can be found in the literature.…”

Alluaudite Na2Co2Fe(PO4)3as an electroactive material for sodium ion batteries

“…The additional 230 mA h g −1 capacity is most probably due to the reduction of the electrolyte over the positive electrode. [25][26][27][28] The first discharge can be segregated to three voltage regions (Fig. 3).…”

“…The same behavior has been observed in various oxyphosphates such as M 0.5 TiOPO 4 (M = Ni, Co and Fe). [25][26][27][28] Fig . 4 shows the differential galvanostatic profile (dQ/dV) of the Na 2 Co 2 Fe(PO 4 ) 3 material.…”