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Photoredox catalysis is a rapidly growing field in which energy gained from light absorption by a molecule is used to form and break chemical bonds to synthesize value-added products. The flexibility of photoredox catalysis has enabled design and realization of highly oxidizing and highly reducing chemical reactions with remarkable selectivity relevant for medicinal chemistry and renewable energy. Design of new chromophores is an important step in the general adoption of photoredox catalysis for large-scale applications where common chromophores such as [Ru(bpy)3]2+ and fac-Ir(ppy)3 are unfeasible due to the high cost of the transition-metal center. This necessitates development of new strategies and new complexes that can drive these chemical reactions with cheaper, more abundant transition-metal centers in assembled architectures that are able to effectively harvest generated photocarriers. Bottom-up molecular design is a useful strategy for identifying new chromophore architectures and incorporating them into functional materials. This work describes the development of two different classes of chromophores and heterogenization of an optically active semiconductor with molecular catalysts.The research described in Chapter 2 describes the synthesis and characterization of molecularly functionalized MoS2 monolayers with transition-metal complexes. The resulting surface is studied using a variety of spectroscopic and physical characterization techniques to validate the presence of the added transition-metal species. The work in Chapter 3 describes the synthesis of some early transition-metal chromophores that are based on isoelectronic substitution of the WC core of emissive tungsten-alkylidyne complexes with a MoC or TaN core to understand the metal-ligand bonding and photophysics of these complexes. These complexes are further studied by protonation to form the corresponding cationic hydride complex to differentiate the proton tautomerization of these hydride complexes in relation to the metal center and triply-bonded heteroatom. In Chapter 4, a computational study of a series of tungsten alkylidyne chromophores demonstrates how peripheral substitution affects excited-state properties of the triplet state. Trends in energies, bond lengths, and densities are studied in order to rationalize experimental photophysical data and suggest future improvements and studies for these complexes. The work described in Chapter 5 describes a second set of chromophores that are based on linear carbene-metal-amide copper complexes using deprotonated acridone as the amide. These complexes emit solely ligand-centered fluorescence. This copper complex is then compared to a potassium-cryptate salt and the parent protonated ligand to understand how deprotonation and coordination affects the ligand-centered photophysical processes.