Finite-Size Modeling Approaches for Materials Screening in Green Hydrogen Production

• Grant number: 25/20478-0
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: January 01, 2026
• End date: December 31, 2028
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Juarez Lopes Ferreira da Silva
• Grantee: Juan Carlos Roldao
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Company: Universidade de São Paulo (USP). Instituto de Química de São Carlos (IQSC)
• Associated research grant: 17/11631-2 - CINE: computational materials design based on atomistic simulations, meso-scale, multi-physics, and artificial intelligence for energy applications, AP.PCPE

Abstract

The global energy transition demands technological solutions that combine sustainability, efficiency, and economic feasibility. In this context, green hydrogen production via water electrolysis powered by renewable sources emerges as a promising alternative to replace fossil fuels in key sectors. However, the overall efficiency of electrolysis remains limited by the kinetic barriers of the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) occurring at the electrodes. The development of efficient, stable, and cost-effective catalysts continues to be one of the major bottlenecks for the large-scale implementation of this technology. This project proposes a high-accuracy theoretical investigation based on finite-cluster models and density functional theory (DFT) simulations to unravel the fundamental mechanisms that govern catalytic activity in transition-metal-based materials. The core innovation lies in employing finite-size models (in contrast to conventional periodic slabs) to explicitly capture local effects such as dopants, structural defects, undercoordinated sites, and heterogeneous chemical environments. In addition, the project will explicitly address fluxionality, i.e., the role of multiple low-energy metastable states beyond the global minimum, providing a more realistic picture of catalytic activity under operando conditions. This strategy is particularly relevant for non-precious and complex materials, where catalytic performance is often determined by well-defined active centers rather than extended surface periodicity. All simulations will be performed using the FHI-aims software, which implements numerically optimized atom-centered orbitals. The workflow will include geometry optimizations, adsorption energy evaluations, vibrational analyses, and mechanistic exploration of reaction steps via the Nudged Elastic Band (NEB) method, enabling the identification of transition states and reaction energy profiles. Key energetic and electronic descriptors, such as adsorption free energies, HOMO-LUMO gaps, d-band centers, and Bader charges, will be extracted and correlated with catalytic performance through volcano plot analysis. In addition, the project integrates data science and machine learning tools to handle the large datasets generated and discover predictive descriptors. Supervised and unsupervised learning algorithms will be used to reveal structure-activity relationships and assist in the selection and design of new catalyst candidates. Expected outcomes include a deeper understanding of electronic and structural factors favoring HER and OER activity in various material classes, such as phosphides, nitrides, carbides, transition metal dichalcogenides (TMDs), layered hydroxides, MXenes, high-entropy alloys (HEAs), and porous frameworks such as MOFs and COFs. On the basis of mechanistic insights, new catalytic motifs will be proposed and benchmarked for their feasibility. This research aligns with the broader objectives of the QTNano group at the Institute of Chemistry of São Carlos (IQSC-USP) and is part of the FAPESP-SHELL project focused on sustainable hydrogen production. The results are expected to support experimental collaborators and ongoing initiatives while contributing to the international community through high-impact publications in the fields of computational catalysis, materials chemistry, and energy conversion. (AU)