Colloidal Zeta Potential Modulation as a Handle to Control the Crystallization Kinetics of Tin Halide Perovskites for Photovoltaic Applications.

Tin halide perovskites (THPs) have demonstrated exceptional potential for various applications owing to their low toxicity and excellent optoelectronic properties. However, the crystallization kinetics of THPs are less controllable than its lead counterpart because of the higher Lewis acidity of Sn2+, leading to THP films with poor morphology and rampant defects. Here, a colloidal zeta potential modulation approach is developed to improve the crystallization kinetics of THP films inspired by the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. After adding 3-aminopyrrolidine dihydro iodate (APDI2) in the precursor solution to change the zeta potential of the pristine colloids, the total interaction potential energy between colloidal particles with APDI2 could be controllably reduced, resulting in a higher coagulation probability and a lower critical nuclei concentration. In situ laser light scattering measurements confirmed the increased nucleation rate of the THP colloids with APDI2. The resulting film with APDI2 shows a pinhole-free morphology with fewer defects, achieving an impressive efficiency of 15.13 %.

First-principles study of electronic structure, sodium diffusion on 2D TiO2monolayers for sodium-ion battery electrodes.

The search for suitable electrode materials is crucial for the development of high-performance Na-ion batteries (NIBs). In recent years, significant attention has been drawn to two-dimensional (2D) oxides as potential NIB electrode materials. In this study, employing the first-principles density functional theory method, we investigate the thermodynamic and kinetic properties of Na adsorption and diffusion behavior on the 2D TiO2(010) monolayer. Our findings demonstrate that the 2D anatase TiO2(010) monolayer exhibits enhanced thermodynamic stability. Furthermore, the Na atoms preferentially adsorb on the top of oxygen atoms within the TiO2(010) monolayer, and their diffusion along the [100] direction is characterized by a low energy barrier of 0.054 eV. This comprehensive analysis sheds light on the structural stability, preferred adsorption sites, and diffusion paths of Na atoms on the 2D anatase TiO2(010) monolayer, providing valuable insights into the nature of the material's structure and Na ion transport. Moreover, the 2D structure of the TiO2matrix facilitates short Na diffusion lengths and a large electrode/electrolyte interface, thereby demonstrating the potential of this material as an NIB electrode material.