Metal–organic frameworks (MOFs) can be exceptionally good catalytic materials thanks to the presence of
active metal centres and a porous structure that is advantageous for molecular adsorption and
confinement. We present here a first-principles investigation of the electronic structure of a family of
MOFs based on porphyrins connected through phenyl-carboxyl ligands and AlOH species, in order to
assess their suitability for the photocatalysis of fuel production reactions using sunlight. We consider
structures with protonated porphyrins and those with the protons exchanged with late 3d metal cations
(Fe2+, Co2+, Ni2+, Cu2+, Zn2+), a process that we find to be thermodynamically favorable from aqueous
solution for all these metals. Our band structure calculations, based on an accurate screened hybrid
functional, reveal that the bandgaps are in a favorable range (2.0 to 2.6 eV) for efficient adsorption of
solar light. Furthermore, by approximating the vacuum level to the pore centre potential, we provide the
alignment of the MOFs' band edges with the redox potentials for water splitting and carbon dioxide
reduction, and show that the structures studied here have band edges positions suitable for these
reactions at neutral pH.Royal Society for an International Exchange Scheme grantVia our membership of the UK's HPC Materials Chemistry Consortium, which is funded by EPSRC (EP/L000202), this work made use of the facilities of ARCHER, the UK's national high-performance computing services, which are funded by the Office of Science and Technology through EPSRC's High End Computing ProgrammeEuropean Research Council through an ERC Starting Grant (ERC2011-StG-279520-RASPA)MINECO (CTQ2013-48396-P)Andalucía Region (FQM-1851)University of Granad
