LAUSR

Abstract Tangerine peels extract mediated silver nanoparticles (TPE-AgNPs) were synthesized by bio-reduction of silver ions using tangerine (Citrus reticulata) peels extract and characterized using by UV–Vis, XRD, TEM, EDAX, DLS and FTIR. The obtained particles were crystalline, round-shaped, monodisperse and stable. TPE-AgNPs exhibit face centre cubic (fcc) structure in Ag0 (111) phase/orientation with dimension a = b = c = 4.0968 A ∘ and α  =  β  =  γ  = 90° and contain cells with volumes 72.42 × 10−6 pm3 and density ( ρ ) 10.19 gcm−3. TPE-AgNPs were evaluated as a new material for application as biocide and inhibitor for acid and microbial corrosion of pipeline (X80) steel in oilfield environments. TPE-AgNPs produced a 3-log reduction in microbial population (Desulfovibio sp) at 2.88 mg/L MIC and inhibited biocorrosion by 76.2% and 61.8% at 303 K and 333 K respectively. At these temperatures, 1.0 g/L TPE-AgNPs inhibited X80 steel corrosion in 1 M HCl by efficiency of 93.9% and 90.3%, respectively. Corrosion inhibition occurs by adsorption of the nanoparticles through C O, C C, C–O and O–H sites which increases charge transfer and film resistances at the steel-electrolyte interface. Complementary techniques such as FTIR, SEM/EDAX support electrochemical and weight loss results. TPE-AgNPs were more thermally stable and efficient inhibitors than the crude extract and can be deployed in oilfield for simultaneous inhibition of acid and microbial induced corrosion.