Subcategory: Materials Science
Juan C. Arango Lozano - Universidad del Turabo
Co-Author(s): Sergio Pinilla and Carmen Morant, Autonomous University of Madrid, Spain Francisco Márquez Linares, Universidad del Turabo, Puerto Rico
Si-based materials, have gained interest as an alternative to graphite for the construction of electrodes for rechargeable lithium-ion batteries, due to the high specific capacity of Si. However, silicon anodes have an inherent problem during cycling performance; lithium ions produce huge volume changes during charge / discharge process in the material, resulting in a rapid capacity fading of the battery. A proposed solution, is the use of silicon nanowires (SiNWs) instead of amorphous Si, starting from a Si-<100>-wafer. Here, is presented an innovative process to grow SiNWs, through metal assisted chemical etching (MACE) process, using Ag. Hypothesis: I) Consumption of Si wafer, is directly related to chemical etching duration and temperature. II) Ag concentration will affect the SiNWs form and size. Results: 1) the growth of the SiNWs was achieved; 2) consumption of all the Si wafer was achieved by modifying the duration of the chemical etching; and 3) The corrosion and porosity appreciated on the as-synthesized SiNWs were considerably reduced, modifying the Ag concentration, improving the uniformity and organization of the SiNWs. Conclusions: 1) The Ag concentration, required for obtaining SiNWs with suitable properties to use in Li-ion batteries was 0.005M; 2) the optimum reaction time and temperature were fixed to 2h30m at 40 ˚C; and 3) MACE process was an appropriate process to obtain SiNWs in a controlled manner. The main objective of this project, is the quality improvement of portable energy devices, reducing the harmful effects of these to environment, preserving all our Caribbean precious natural resources.
Funder Acknowledgement(s): Department of Energy (DoE) thorough the Massie Chair program. PRLSAMP fellowship, for funding the instance at Madrid, Spain. The applied physics department at Autonomous University of Madrid for allowing me develop this stage of the project. The Puerto Rico Energy Center (PREC) for allowing the use of its facilities to develop the characterization of the obtained material. The applied physics department at Autonomous University of Madrid for allowing me develop this stage of the project. The Puerto Rico Energy Center (PREC) for allowing the use of its facilities to develop the characterization of the obtained material.
Faculty Advisor: Francisco Márquez Linares, firstname.lastname@example.org
Role: I did the whole synthesis process at Autonomous University of Madrid, and the characterization of the resulted material as well.