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In this study, silver‐titanium dioxide/graphene aerogel (Ag−TiO2/GA−ATG) was synthesized via chemical reduction using ethylene diamine (EDA). The effects of reductant doses on the formation of the three‐dimensional structure and the photocatalytic degradation efficiency of ATG were evaluated with five different volumes (20, 30, 40, 50, and 60 μL), corresponding to the ATG1, ATG2, ATG3, and ATG4, respectively. The results showed that 40 μL of EDA was the suitable condition for the formation of ATG three‐dimensional structure. Characterizations revealed that ATG3 was successfully synthesized with distinctive peaks of Ag and TiO2 in the X‐ray diffraction patterns whilst scanning electron microscope and high resolution transmission electron microscope images showed a porous structure, silver nanoparticles and TiO2 with an average size of 10–25 nm were uniformly distributed on the graphene surface. Furthermore, ATG3 possessed the highest photocatalytic capability to deteriorate methyl orange with an efficiency of up to 99.53 % with a catalyst dose of 0.3 mg/mL, superior compared to those of TiO2 and TiO2/GA. The radicals scavenging experiments elucidated ⋅O2 ${{{\rm { O}}}_{{\rm { 2}}}^{{\rm { \char60 M-\char62 }}}}$ to majorly contribute to the photodegradation process. Moreover, ATG3 showed high recyclability, which retains 80 % of yield even after 10 cycles. Those findings proved that ATG has high potential in the environmental remediation field. [ABSTRACT FROM AUTHOR]

• Fe 3 O 4 /GAs were synthesized in the presence of ethylenediamine as a reducing agent. • Effect of Fe 3 O 4 :GO mass ratio was studied. • The adsorption process of Fe 3 O 4 /GA for BPA was investigated. • The adsorption mechanism of Fe 3 O 4 /GA for BPA adsorption was determined. In this study, magnetic iron oxide nanoparticles decorated graphene aerogel (Fe 3 O 4 /GA) with different Fe 3 O 4 :GO mass ratios of 0.5:1, 1:1, and 2:1, which were synthesized in the presence of ethylenediamine as a reducing agent. The suitable mass ratio of Fe 3 O 4 :GO was determined to be 1:1 for the preparation of Fe 3 O 4 /GA (FGA2). The FGA2 was characterized by vibrating sample magnetometer, contact angle and Fourier transform infrared spectroscopy, X–ray diffraction, transmission electron microscopy, scanning electron microscope, Raman spectroscopy and Brunauer–Emmett–Teller specific surface area. The adsorption process of FGA2 for bisphenol A (BPA) was studied by single factor experiments including contact time, pH and initial BPA concentration. The adsorption data were followed the intraparticle diffusion and pseudo-second-order kinetic models. The maximum adsorption capability of FGA2 for BPA from Langmuir isotherm model was calculated to be 253.80 mg/g. The adsorption mechanism of FGA2 for BPA was mainly described by π−π interactions. Based on these results, the FGA2 could be concerned as an efficient adsorbent for the removal of BPA from water. [ABSTRACT FROM AUTHOR]