Table 6 The XPS spectra carves fitting results of A. tumefaciens S12 before and after adsorption of Pb²⁺, Cd²⁺ and Zn²⁺

O1s

C-O

532.7

C-O

532.8

C-O

532.8

C-O

532.8

C = O/C–OH

531.2

C = O/C–OH

531.5

C = O/C–OH

531.5

C = O/C–OH

531.5

N1_S

-NH₂/-NH

400.0

-NH₂/-NH

400.1

-NH₂/-NH

399.9

-NH₂/-NH

399.9

-

-

-NH₃⁺

401.4

-

-

-

-

P2_P

P-O

133.1

P-O

132.9

P-O

133.3

P-O

133.2

P = O

133.9

P = O

133.7

P = O

134.1

P = O

134.0

Pb 4f

-

-

Pb 4f 5/2

143.2

-

-

-

-

Pb 4f 7/2

138.3

-

-

Cd 3d

-

-

-

-

Cd 3d3/2

411.8

-

-

-

-

Cd 3d5/2

405.1

Zn 2p

Zn 2p1/2

1021.9

Zn 2p3/2

1044.9