Ultrafast time-resolved spectroscopy has been applied to resolve the formation of separated electron-hole pairs (e --h + ) between linkers and metal centres in metal-organic-frameworks (MOFs). Douhal and co-worker have shown that in Zr-naphtalene-dicarboxylate (Zr-NDC) MOFs the charge separation takes place within less than 200 fs, leading to the formation of electrons and holes localized on the Zr clusters and on the naphtalene linkers, respectively. The (e --h + ) pairs can be engaged in oneelectrons redox reactions. The analysis of the decays shows also that the electron-hole recombine radiatively with different lifetimes varying from the hundreds of ns to the µs time scale, suggesting the presence of heterogenous trapping environments in the materials. In additions, time-resolved measurements also revealed that the (e --h + ) formation is in competition with the formation of excimers or energy transfer. The role of the topology of the MOFs framework in controlling these competitive pathways has also been evidenced for Zr-(p-benzoic acid)-pyrene MOF materials (NU-901, NU-1000) and in MOF PCN-223, for which a hopping mechanism of energy transfer from the excited chromophores to N-protonated linkers acting as traps has been proposed. The titanium-based MOF family MIL-125(Ti) have also attracted a lot of attention for solar fuel generation. The photocatalytic activity of the MIL-125(Ti) is due to a photoinduced electron transfer from the HOMO orbitals of the ligand into the LUMO orbitals localized on the Titanium-oxo clusters. The incorporation of amino (-NH2) group in some of the ligand is shifting the absorption wavelength of the MOF to the visible spectral range and favour the stabilisation of the electron-hole pair, as it has been shown by transient UV-vis and MidIR femtosecond spectroscopy . For MIL-125 derivatives, and MOFs in general, understanding the crucial influence on the ligand substituent on the photocatalytic activity is of great importance to optimize the applications. Interestingly, by comparing the effect of triethanolamine (TEOA) and of methanol (MeOH) as hole scavengers for the photocatalytic HER process with MIL-125(Ti) and NH2-MIL-125(Ti), Eder and co-workers have shown that the charge stabilization on the amino group is not favourable to the hole scavenging by MeOH, while TEOA molecules degrade the MIL-125(Ti). These works illustrate the complex interplay between the different and often competitive primary photophysical and photochemical processes governing the electron-hole formation and reactivity in microporous photocatalysts. The properties of the excited states, the mode of energy transfer and of charge separation toward the metal centre vary finely with the nature and composition of the porous materials. Thus, there is still a pressing need for more systematic and in-depth investigation of these ultrafast processes to be carried out in line with the design of new and promising photocatalyst. The work reported hereafter aims to contribute to that field by focusing on the excited photochemistry of metal containing conjugated microporous polymers (CMP), a class of porous materials for which the application of the time-resolved spectroscopy is still quite limited compared to MOFs, despite their interest for photocatalysis applications .