B 0●●●00 OOOOC 8888°88888 Solution B 80 ● OOOOOOOOO u 860 40 ●o●● OOOOO ●oo●oOO ●o●o●o● OOOOOO 20 Solution 0 ●o●0o●o 30-20-10010203040 ●●O O●o●●O r. um ●0●●ooo●0o● Original cu-Ni interface ●o●●●o●o●o●