1. S. H. Lee, D. W. Lee and S. H. Lee, Korean J. Met. Mater. 55 (9), 637–644 (2017).
2. Historical Copper Spot Price Chart, Available at: https://www.providentmetals.com/spot-price/chart/copper/ (accessed 20 September 2019).
3. Historical Silver Spot Price Chart, Available at: https://www.providentmetals.com/spot-price/chart/silver/ (accessed 20 September 2019).
4. A. A. Istratov and E. R. Weber, J. Electrochem. Soc. 149 (1), G21–G30 (2002).
5. C. Modanese, M. Wagner, F. Wolny, A. Oehlke, H. Laine, A. Inglese, H. Vahlman, M. Yli-Koski and H. Savin, Sol. Energy Mater. Sol. Cells 186, 373–377 (2018).