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LiFePO₄ nanocrystals were synthesized in various polyol media without any further post-heat treatment. The LiFePO₄ samples synthesized using three different polyol media namely, diethylene glycol (DEG), triethylene glycol (TEG), and tetraethylene glycol (TTEG), exhibited plate and rod-shaped structures with average sizes of 50–500 nm. The X-ray diffraction (XRD) patterns were indexed on the basis of an olivine structure (space group: Pnma). The samples prepared in DEG, TEG, and TTEG polyol media showed reversible capacities of 123, 155, and 166 mAh/g, respectively, at current density of 0.1 mA/cm² with no capacity fading and exhibited excellent capacity retention up to the 50th cycle. In particular, the samples showed excellent performances at high rates of 30 and 60 C with high capacity retention. It is assumed that the nanometer size materials (~50 nm) possessing a highly crystalline nature may generate improved performance at high rate current densities.

Nanostructured LiFePO₄ is appealing cathode material for rechargeable lithium batteries. Herein, however, we report the intriguing anode properties of carbon coated LiFePO₄ nanocrystals. In the potential range of 0–3.0 V, the LiFePO₄ nanocrystal electrodes afford high reversible capacity of 373 mAhg${}^{-1}$ at a current rate of 0.05 Ag${}^{-1}$ and retains 239 mAhg${}^{-1}$ at a much higher rate of 1.25 Ag${}^{-1}$. In addition, it is capable of sustaining 1000 cycles at 1.25 Ag${}^{-1}$ without any capacity fading. Such superior properties indicate that nanostructured LiFePO₄ could also be promising anode for rechargeable battery applications.

PbS nanocrystals with octahedron shape are synthesized by a low temperature approach with presence of cation/anion surfactants in aqueous solution. CdS quantum dot sensitized solar cells (QDSSCs) based on these novel octahedron shaped PbS counter electrodes (CEs) are fabricated for the first time, achieving PCE of 1.54%. It is observed that the octahedron shaped PbS CE shows higher electrocatalytic activity compared with the Pt CE, indicating that the PbS nanocrystals with a uniformly distributed size is a superior candidate as CEs for QDSSCs application. This work may provide new route for preparing PbS from aqueous solvent medium through a simple synthesis route.