Global warming and ecosystems contamination by fine chemicals industry have motivated to explore and develop cleaner and lower cost strategies for the energy conversion and transformation of organic compounds. [1,2] Solar-driven catalysis via photo(electro)catalysis (PEC) has emerged as a promising route to store sunlight into chemical bonds. Commonly, PEC water splitting has been studied as an approach to reduce H þ to produce green hydrogen with the oxygen evolution reaction (OER) as electron donor. As this reaction is kinetically very demanding, water can be substituted by organic compounds as electron donors due to their faster oxidation kinetics. This would increase the H 2 evolution kinetics while concomitantly producing high added-value chemicals, remediating industrial wastewaters, [3][4][5][6][7][8] and making use of semiconductor materials with highly oxidizing/ reducing power. [8,9] In a simple manner, when a semiconductor is illuminated with an energy equal or higher than its bandgap, charge carrier photogeneration and separation is promoted. Photogenerated holes are formed in the valence band (VB), where oxidation reactions take place, while electrons with higher free energy are located in the conduction band (CB) to trigger reduction reactions. [9][10][11] This is the basis of photocatalytic (PC) reactions led through nanoparticle system (Figure 1A). Then, when the photomaterial is deposited in a conducting substrate, PEC oxidation and reduction reactions can be carried out in separate compartments. [9,12,13] Here, one type of photocarriers migrate to the photoelectrode surface to conduct an interfacial PEC semireaction, while the other kind of photocarrier is transported through the external circuit to a counter electrode and perform the complementary PEC semireaction (Figure 1B). [9] Metal oxides, chalcogenides, and heterojunctions based on these materials have attracted significant attention as photocatalysts due to their wide gamut of low-cost synthetic protocols available for their preparation and facile charge carrier extraction [9,10,[13][14][15][16] Although metal oxide photoelectrodes show a high performance under UV light, high stability, and low toxicity in some cases, they are often limited by their poor light harvesting efficiency toward near-infrared wavelengths. Additionally, metal oxide photoelectrodes tend to exhibit a fast carrier recombination as well as poor charge accumulation/transport kinetics, hindering their applicability in solar water splitting applications. [10,17,18] In the case of chalcogenides, their superior optoelectronic properties are in contrast with the low stability promoted by their fast photodegradation. To reduce photodegradation and charge carrier recombination and to overcome charge transport/accumulation kinetic limitations, inner-sphere redox couples and organic substrates are commonly used to accelerate