Cyclic Calcium Phosphate Electrodeposition on Porous Silicon

Calcium phosphate (CaP) on porous silicon (PSi) has been proposed to generate composite bioceramics for osseous tissue regeneration. Usually, CaPs prepared by biomimetic and electrochemical methods stem from a single aqueous solution. We propose herein a diversified method that consists on independent calcium (Ca) and phosphate (P) electrodeposition cycles. In this way, the PSi layer is sequentially immersed in the Ca-P solutions, and the electrical current reversed in accordance, allowing both species to react on the porous matrix during a given number of cycles. The main advantage of our proposed method is that the individual variables of each step can be controlled and studied independently. That means that the main electrodeposition parameters such as pH, current density and reaction time can be adjusted independently for Ca and P solutions. The characterization by SEM, FTIR, XRD and EDX demonstrates that, for selected conditions, our proposed method allows depositing a hydroxyapatite layer on PSi.