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Adsorption in the dark(Ads dark ) of MB, first-order apparent rate-constants (k app ), square linear regression factor (R 2 ), photocatalytic activity relative to ZnO (ϕ photo ) b
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Photodegradation of methylene blue (MB) was studied on ZnO in presence of home-made biochars prepared by different methods. MB photodegradation was performed under UV-visible irradiation to verify the scaling-up of ZnO-AC hybrid materials. It was verified that oxygenated surface groups on carbon were photochemically active in the photodegradation o...
Contexts in source publication
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... adsorbed After 60 min adsorption in the dark. b ϕ photo = (k app-i /k app-TiO2 ). a b values after 60 min are summarized in Table 2. It can be seen that there are no additive effects in the adsorption capacities of ZnO and AC after they are mixed. ...
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... can be seen that there are no additive effects in the adsorption capacities of ZnO and AC after they are mixed. This can be easily verify from adsorption values in Table 2 obtained after achieve the equi- librium of adsorption. This is in agreement with a strong interaction between ZnO and AC previously reported by our group for ZnO/AC [6] and TiO 2 /AC [9] binary photocatalysts. ...
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... a first-order reaction mechanism [4], the linear regressions of the kinetic data from Fig. 3 was performed to estimate the first-order apparent rate-constants (k app ). Table 2 ...
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... by the expression: ϕ rel = (k app-i /k app-ZnO ). It can be seen from k app values in Table 2 that with the exception of ZnO/AC H3PO4-5% the others ZnO-AC hybrid materials have higher photoactivity than that obtained on ZnO alone and this enhancement was up to about 2.5 times higher on ZnO/AC Zn- Cl2-5% . It is interesting to point out that no correla- tion between the MB adsorbed in the dark and the photoactivity was detected indicating that besides the texture the surface functionalities of AC play an important role upon the photoactivity of ZnO. ...
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... adsorbed After 60 min adsorption in the dark. b ϕ photo = (k app-i /k app-TiO2 ). a b values after 60 min are summarized in Table 2. It can be seen that there are no additive effects in the adsorption capacities of ZnO and AC after they are mixed. ...
Context 6
... can be seen that there are no additive effects in the adsorption capacities of ZnO and AC after they are mixed. This can be easily verify from adsorption values in Table 2 obtained after achieve the equilibrium of adsorption. This is in agreement with a strong interaction between ZnO and AC previously reported by our group for ZnO/AC [6] and TiO 2 /AC [9] binary photocatalysts. ...
Context 7
... a first-order reaction mechanism [4], the linear regressions of the kinetic data from Fig. 3 was performed to estimate the first-order apparent rate-constants (k app ). Table 2 ...
Context 8
... by the expression: ϕ rel = (k app-i /k app-ZnO ). It can be seen from k app values in Table 2 that with the exception of ZnO/AC H3PO4-5% the others ZnO-AC hybrid materials have higher photoactivity than that obtained on ZnO alone and this enhancement was up to about 2.5 times higher on ZnO/AC ZnCl2-5% . It is interesting to point out that no correlation between the MB adsorbed in the dark and the photoactivity was detected indicating that besides the texture the surface functionalities of AC play an important role upon the photoactivity of ZnO. ...
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Practitioner Points
ZnO NRs/BC hybrids achieve a remarkable 61.79% efficiency in removing MB pollutants, surpassing other carbon materials.
MB removal using BC‐based materials follows pseudo‐first‐order kinetics.
BC grains exhibit unique distribution patterns on ZnO NRs, with densely packed grains atop contributing to higher MB removal.
FTIR analysis confirms increased MB‐related bond vibration, supporting the effectiveness of ZnO NRs/BC hybrids for water pollutant removal.
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