LiFePO 4 has an interesting spin-polarized electronic structure showing a (3dv) 5 (3dV) 1 electron configuration of the Fe 2+ ion. In this work, we have experimentally evidenced the valence electronic structure of LiFePO 4 and of its delithiated compound FePO 4 by X-ray photoelectron spectroscopy (XPS), which allows a visualization of the occupied densities of states (DOS) in the valence band. XPS valence spectra were compared with the DOS obtained from DFT calculations by considering GGA and GGA + U approaches. Thanks to electrochemical extraction/insertion of Li + ions in LiFePO 4 /FePO 4 , it was possible to display the Fe 3d spindown electron of LiFePO 4 , which is not present in the valence spectrum of FePO 4 . We show that the study of XPS valence spectra is an efficient way to access the lithium insertion rate in Li x FePO 4 positive electrode materials for lithium-ion batteries. Besides the contribution to the Li-ion battery field, this paper is also a rare example of experimental evidence of a spin-resolved electronic structure from in-lab XPS experiments.

The behavior of confined anticancer carboplatin (CPT) molecules in a single (10, 10) boron nitride nanotube (BNNT) was studied by means of molecular dynamics simulations. Our study revealed a very large storage capacity of BNNT. Analysis of the energy profiles depending on the number of confined molecules, and on their spatial organization allowed us to quantify the ability of BNNT to vectorize CPT. Indeed, BNNT despite its small radius presented a large inner volume that favored stable encapsulation of multiple active anticancer molecules. Moreover, in our molecular dynamics simulations, the empty BNNT and the BNNT filled with CPT diffused spontaneously to the cell membrane and were able to passively enter inside lipid bilayers by a lipid-assisted mechanism. This property has been used to deliver naturally anticancer drugs to cellular targets. Using this enhanced drug delivery system, we have provided a definitive solution to the problem of drug release and have thus opened up a new way of targeting cancer cells. Indeed, regardless of the mode of action of the platinum complex towards the cell, the delivery of the drug on site should limit the side effects of the drug.