A higher binding energy means generally that the partial charge on the atom is slightly more positive, i.e. the atoms binding to the Cu are weaker electron donors or stronger electron withdrawers.

Whether that's good or bad in your particular case is something you have to figure out either by reading literature on related systems or by correlating the shift to other quantities you're interested in.

Shifts to higher binding energy indicate a chemical reaction with a change to a higher positive charge of the metal i.e. oxidation.

Thank you so much.