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Metal oxides-based heterojunction fabrication is a promising strategy to eliminate antibiotics from wastewater via adsorption-photocatalysis. ZnLa x Bi 2−x O 4 hybrids with various La/Bi molar ratios were fabricated for enhancing the adsorption-photocatalytic elimination of tetracycline hydrochloride (TCH). Oxygen-defected ZnLa x Bi 2−x O 4 composites provided the sufficient sites for photon capture and pollutants adsorption. In addition, the tight p-n-p type interface among oxygen-defected La 2 O 3 , ZnO, and spinel ZnBi 2 O 4 favored the rapid transfer and migration of photo-excited e-/h+ pairs, enlarging the visible light utilization. Hence, ZnLa x Bi 2−x O 4 samples had the better adsorption-photocatalytic activity than ZnLa 2 O 4 and ZnBi 2 O 4 for TCH removal. Langmuir and second-order models well described the adsorption isotherms and kinetics of ZnLa x Bi 2−x O 4 samples, respectively. The adsorption capacity of optimal ZnLa 1.75 Bi 0.25 O 4 with a La/Bi molar ratio of 7:1 was 406.85 mg g−1, and its removal efficiency of 210 mg L−1 TCH solution was 98.04 % within 150 min. The change in valence states of surface compositions induced to the declined removal efficiency of ZnLa 1.75 Bi 0.25 O 4 to 91.95 % after five cycle times. [Display omitted] • ZnLa x Bi 2−x O 4 heterojunctions had the excellent adsorption-photocatalytic activities. • The adsorption capacity of optimal of ZnLa 1.75 Bi 0.25 O 4 was 406.85 mg g−1. • The removal efficiency of 210 mg L−1 TCH solution over ZnLa 1.75 Bi 0.25 O 4 was 98.05 %. • Langmuir and second-order models well fitted with the adsorption behaviors of ZnLa x Bi 2−x O 4. [ABSTRACT FROM AUTHOR]