2020 年 99 巻 8 号 p. 82-87
Demands for batteries have been increasing each year globally. This results in an enormous number of waste batteries, especially non-rechargeable types. It can pose severe environmental and health hazards if disposed of improperly. The consumers are generally not aware of how waste batteries should be properly disposed, thus, they usually end up in landfills worsening its risks. Hence, determining a more valuable alternative usage is a sustainable solution. In this study, graphite rods from the waste primary (zinc-carbon) batteries were utilized to produce conductive ink. Graphite rods were systematically removed from the spent batteries, cleaned with acetone to remove the plastic coating, and dried. It was then electrochemically exfoliated by applying 10 V and 2 A while submerged in an H2SO4 solution (1 M). The resulting powders were filtered, rinsed with distilled water until neutral pH, and oven-dried (80 °C). These were then dispersed in silver-ammonia solution and hydrothermally reacted at 150 °C for 5 h. Sodium silicate solution was used as a dispersing medium for the reduced graphene oxide (rGO) powder producing conductive ink. The ink demonstrated a good surface adhesivity, very low resistivity (<30 μΩ∙m), and consistent even after 500 bending cycles. Also, Ag@rGO powder’s morphology, surface characteristics, and physicochemical properties have been evaluated using XRD, Raman, and FE-SEM.
