In the context of global warming and related carbon capture & utilization strategies, the thermocatalytic hydrogenation of CO2 is one possible route toward the production of “green” fuels and platform chemicals [1]. As far as methanol production is concerned, besides the industrial Cu/ZnO/Al2O3 syngas-to-methanol catalyst, some other materials have been proposed to increase the methanol yields and the catalyst stability, but they mostly involve rare or strategic elements such as Au, Pd, In, Ga, Zn, and Ce. In this work, we have assessed the potential of early transition metals (V, Cr, Mn, Nb, Mo, Ta, W, Re) supported on various commercial or homemade titanias in the gas-phase CO2+H2 reaction in a high-pressure flow fixed bed reactor. The catalysts, prepared by wet impregnation-calcination, consisted of metal single atoms and/or clusters anchored on the support, as visualized by scanning transmission electron microscopy. The reference titania materials were commercial anatase (Tronox DT51D, 85 m2/g) and anatase-rutile mixture (80:20%, Evonik P25, 61 m2/g). The metal screening led to the selection of low-loading Mo and Re-based catalysts as the most active ones. The catalytic performance of Mo/TiO2, which was previously regarded as inactive for CO2 hydrogenation to methanol [2,3], is highly sensitive to the Mo loading (0.1-10 wt%) and the titania type (phase composition, surface area, nanoparticle morphology). In particular, molybdenum supported at intermediate loading (3 wt%) on rutile titania nanorods exhibits unexpected efficiency in terms of total activity, methanol yield, and methanol selectivity. Catalyst characterization by various techniques including NAP-XPS and operando XAS, suggests that the most active sites consist of atomically-dispersed and partially oxidized Mo species in intimate interaction with titania [4]. Like Mo/TiO2, the Re/TiO2 system containing a similarly low proportion of supported metal atoms is stable and catalyzes mostly CO, methane and methanol production from CO2 and H2. However, it is more active than its molybdenum counterpart. Moreover, Re/TiO2 favors the formation of higher alkanes and alcohols, and the products distribution is even more dependent on the metal loading and the titania type than for Mo/TiO2. From Re/RNR to Re/P25, the main reaction route switches from competitive reverse water-gas shift and CO2 methanolation, to CO2 methanation. Complementary CO hydrogenation tests, CO2 TPD, H2-D2 exchange and operando DRIFTS experiments provide additional insights into the mechanistic similarities and differences between those catalysts. [1]J. Zhong, X. Yang, Z. Wu, B. Liang, Y. Huang, T. Zhang, Chem. Soc. Rev. 49 (2020) 1385–1413. [2]J. Barrault, J. Urresta, Comptes Rendus Académie Sci. - Ser. IIC - Chem. 2 (1999) 167–174. [3]T. Toyao, S. Kayamori, Z. Maeno, S.M.A.H. Siddiki, K. Shimizu, ACS Catal. 9 (2019) 8187–8196. [4]T. Len, M. Bahri, O. Ersen, Y. Lefkir, L. Cardenas, I.J. Villar-Garcia, V.P. Dieste, J. Llorca, N. Perret, R. Checa, E. Puzenat, P. Afanasiev, F. Morfin, L. Piccolo, Green Chem. 23 (2021) 7259–7268.