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In the independent state, PA and GO are too far away from each other to induce any interactions and energy lowering. Accordingly, the energy of the independent state is calibrated to zero as the energy benchmark, signified by pink dotted line. In the combined state, however, PA and GO draw near to form the stable framework PA-GO driven by energy lowering. Structural diagram of PA, GO and PA-GO are presented as inset. [Display omitted] • Phytic acid functionalized graphene oxide (PA-GO) was facilely fabricated. • C 6 H 6 O 24 P 6 12- is the dominant species of phytic acid in PA-GO fabrication system. • Combination mechanism based on electron transfer induced energy lowering for PA-GO. • PA-GO exhibits high adsorption capacity for ionic dyes in five consecutive cycles. Phytic acid functionalized graphene oxide (PA-GO) has encouraging application in environmental treatment. Herein, structure of PA-GO fabricated by hydrothermal method was inspected. Firstly, the aqueous species distribution and ionization states of phytic acid (PA) and graphene oxide (GO) under varying pH was analyzed according to equilibrium thermodynamics to clarify the primary interacting species involved in PA-GO fabrication. Secondly, the hard-soft acid-base (HSAB) theory and spectroscopic characterizations (XPS, FTIR, Raman, UV–Vis and fluorescent spectra) were employed to elucidate the plausible interactions existing in PA-GO. Thermodynamic deduction indicates, C 6 H 6 O 24 P 6 12- is the dominant species of PA, while –OH and –COO- are the dominant state of graphene oxide groups in PA-GO fabrication system. HSAB theory illuminates, the primary interactions occurs between deprotonated oxygen O(O-) and bridged oxygen O(-O-) of phytic acid with hydroxyl group O(Ar-OH) and π electron of graphene oxide. Moreover, electron flows from GO towards PA to induce energy lowering whereby PA-GO is stabilized. HSAB theory prediction was substantiated by spectroscopic analyses. Furthermore, PA-GO efficiently removes ionic dyes in five consecutive cycles with high adsorption capacity. This work may shed light on the fabrication chemistry of PA-GO framework serving as a potential adsorbent. [ABSTRACT FROM AUTHOR]