Table 1.

FT-IR investigation of functional group signals and bond assignment.

Functional group vibration	IR signal in PB-extract	IR signal in Pd-NPs	References
‒OH phenolic stretch	3507–3335	3468–3417	Bagad and Khan (2015)
C‒H stretch of aliphatic hydrocarbons	2986	2974	Ali et al. (2015)
C–H stretch	2086	-	Paluszkiewicz and Kwiatek (2001)
C=C aromatic ring stretch	1643	1637	Wang et al. (2014)
C–N stretch and C-H bending of alkanes	1402	1401	Balaji et al. (2017)
C–O stretch of ring-oxygen	1247	1247	Bagad and Khan (2015)
C–N stretch of aliphatic amines	1062	1059	Wang et al. (2014)