The overarching research goals of Dinolfo Group at Rensselaer are to understand the fundamental aspects of light and electrochemically driven chemical reactions that are central to solar energy conversion, artificial photosynthesis, and green chemistry transformations. We synthesize inorganic and organic model systems and apply electrochemical and spectroscopic methods to characterize and understand the important mechanistic aspects of redox and photochemical reactions.
Methods: Organic and Inorganic Synthesis, Coordination Chemistry, Surface Chemistry, Electrochemistry, Spectroelectrochemistry, Spectroscopy, Electronic Structure Calculations.
Research topic areas include:
Characterization of Photoinduced Charge-Transfer Systems via Electroabsorption Spectroscopy
Photoinduced charge-transfer processes are important processes for many different energy and green chemistry applications, including solar-to-electrical energy conversion, artificial photosynthesis, and photoredox catalysis. Electroabsorption and electroemission spectroscopy, which is based on the Stark-Lo Surdo effect, can directly measure the charge-transfer characteristics of molecular excited-states. We are utilizing this advanced spectroscopic technique to characterize the light-driven charge-separation process of various organic and inorganic chromophores that have been developed for these applications. We are also utilizing the Stark-Lo Surdo effect to quantify electric fields within molecules generated by macrodipoles. (Publications: JPCA 2025)
Proton-Coupled Electron-Transfer Model Systems
Proton-coupled electron transfer (PCET) reactions are integral components of many different biochemical and enzymatic processes, as well as renewable energy applications, including artificial photosynthesis. While our understanding of single-electron transfer events is reasonably well established, the fundamental underpinnings of PCET reactions are only recently coming to light and new theories have been established to predict reaction rates. Biomimetic model complexes have played a significant role in the development of theories describing the rates of PCET reactions by providing systems to test how the structure, driving force, redox potentials, and reorganization energies affect the electron transfer (ET) rates. We are synthesizing imidazole-functionalized phenol compounds to study the fundamental molecular properties that control PCET reactions.
Redox Coupled Spin-Crossover
Redox-coupled spin-crossover (RCSCO) processes are often observed in first-row transition metals such as Fe and Co, where low oxidation states favor high-spin electronic configuration, while higher oxidation states prefer low-spin. Such coupled reactions often lead to interesting electrochemical behavior that can be utilized for a range of applications where redox-bistability is needed. We are interested in developing nanoscale thin films of coordination compounds that undergo RCSCO to create efficient electrochromic devices. These materials would be useful in a wide variety of electro-optical applications, including smart windows, displays, and optical memory devices. (Publications: ICA 2024, JCC 2016)
Molecular Multilayer Light Harvesting Assemblies
We have developed a novel layer-by-layer fabrication technique for the controlled growth of molecular multilayer assemblies on oxide and electrode surfaces. The flexibility of this process permits us to incorporate a wide variety of individual molecular building blocks, which in turn allows us to target specific electrochemical and photophysical properties. Optimization of the energy and charge transfer processes in these films would enable the creation of broadband light harvesting arrays for molecular-based solar cells and artificial photosynthetic devices. (Publications: ACS AMI 2016, ACS AMI 2015, RSC Adv 2014, ACS AMI 2013)
Molecular Electrocatalysts for Water Splitting and Artificial Photosynthesis
We are interested in developing bio-inspired, molecular electrocatalysts that will allow for the efficient conversion of sunlight into stored solar energy in the form of chemical fuels. We are using a biomimetic approach to duplicate the photosynthetic processes found in Nature. We have synthesized several bimetallic complexes, using earth-abundant first-row transition metals, that are able to electrochemically oxidize water to oxygen, and reduce protons to hydrogen. We employ spectroscopy and electrochemical methods to characterize these catalysts and density functional theory calculations to predict reaction mechanisms. (Publications: IC 2020, JPCC 2014, ICA 2014, IC 2014)
