@article{scholars12887, publisher = {John Wiley and Sons Ltd}, volume = {95}, journal = {Journal of Chemical Technology and Biotechnology}, number = {8}, year = {2020}, note = {cited By 27}, title = {Photocatalytic reduction of CO2 to methanol over ZnFe2O4/TiO2 (p{\^a}??n) heterojunctions under visible light irradiation}, pages = {2208--2221}, doi = {10.1002/jctb.6408}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85082341707&doi=10.1002\%2fjctb.6408&partnerID=40&md5=8dfe55a2d04c0f7669a17ccd4586e02a}, issn = {02682575}, author = {Iqbal, F. and Mumtaz, A. and Shahabuddin, S. and Abd Mutalib, M. I. and Shaharun, M. S. and Nguyen, T. D. and Khan, M. R. and Abdullah, B.}, keywords = {Annealing; Carbon dioxide; Heterojunctions; Iron compounds; Irradiation; Light; Methanol; Photocatalytic activity; Titanium compounds, Hydrothermal treatments; Interfacial interaction; Morphological structures; Photocatalytic reduction; Post annealing treatment; Semiconductor composite; Visible-light irradiation; Visible-light photocatalysts, Zinc compounds, carbon dioxide; methanol; nitrate; titanium dioxide; zinc, Article; calcination temperature; chemical composition; chemical structure; comparative study; crystal structure; electron diffraction; energy dispersive X ray spectroscopy; high resolution transmission electron microscopy; light intensity; molecular stability; oxidation; oxidation reduction reaction; photocatalysis; reduction (chemistry); surface area; synthesis; ultraviolet radiation}, abstract = {BACKGROUND: The development of visible light photocatalysts for CO2 reduction into methanol is a challenge, as most of the reported photocatalysts can only work in a UV light environment. Slow kinetics and poor selectivity of CO2 towards methanol are currently two significant drawbacks limiting the practical application of CO2 reduction into methanol. RESULTS: A ZnFe2O4/TiO2 heterojunction with a ratio of unity was found to lead to the highest methanol yield of 693.31 {\^I}1/4mol (g cat){\^a}??1 under a light intensity of 100 mW cm{\^a}??2. This photocatalyst also possessed the highest BET surface area of 6.5211 m2 g{\^a}??1 and better morphological structure, as compared with other ratios (1:2, 2:1 w/w). Interestingly, a loading of 1 g L{\^a}??1 of ZnFe2O4/TiO2 (1:1) heterojunction photocatalyst in the pre-annealing treatment of ZnFe2O4 at 900 {\^A}oC and post-annealing treatment of ZnFe2O4/TiO2 (1:1) composite at 500 {\^A}oC revealed that there was an enhancement in the interfacial interaction, and subsequently an efficient photoreduction of CO2 into methanol. CONCLUSIONS: This study demonstrates facile fabrication of p{\^a}??n heterostructured phototcatalysts for reduction of CO2 with marked improvement in methanol yield under visible light irradiation. It provides a viable route for exploring the effects of composition, hydrothermal treatment, and pre-/post-annealing treatment of hybrid semiconductor composites used to scale up photocatalytic CO2 conversion in solar fuel-based devices. {\^A}{\copyright} 2020 Society of Chemical Industry} }