“…Significant research effort has been devoted to study the interactions of Cu 2+ with aluminum oxide surfaces, aiming to develop predictive models of Cu 2+ concentration and speciation in natural waters [5,7,[9][10][11][12][13][14][15][16][17]. There are three general conclusions from these previous studies [5,7,[9][10][11][12][13][14][15][16][17]: (1) Most researchers concluded that Cu 2+ forms inner-sphere complexes with oxide surfaces.…”