The last decade has witnessed tremendous progress in the development of computer simulation based on quantum mechanical description of the interactions between electrons and between electrons and atomic nuclei with electrode potentials taken into account–promoting the possibility to model electrocatalytic reactions. The cornerstone of this development was laid by the widely used computational hydrogen electrode method which involves a posteriori correction of standard constant charge first principles studies in solvent environment. The description of this technique and its contribution to our effort to understand electrocatalytic reactions on the active sites of metal-based nanoparticles are reviewed. The pathways and energetics of the relevant elementary reactions are presented. We also discussed a recent attempt in the literature to account for the inflow and outflow of electrons from the electrode as electrochemical reactions proceed, which has been greatly assisted by the development of density functional theory within the grand canonical framework. Going beyond the computational hydrogen electrode method by explicit incorporation of electrode potential within the calculations permits access to more detailed insights without requiring extra computational burden.

For the majority of gold nanoclusters (NCs), their water insolubility, low photoluminescence (PL) intensity, and less understood photostability are three critical factors that limit their application in the biomedical and photocatalysis fields. In this study, we report a polymer wrapping method for phase transfer of organic soluble NCs into aqueous phase without degrading the electronic and optical properties, and such materials are further demonstrated for robust photocatalysis in water. We first synthesized a Au₁₈(DMBT)₁₄ NC (DMBT = 2,4-dimethylbenzenethiolate) and found that the aromatic ligands confer a greatly enhanced antioxidation capability of the NC compared to the Au₁₈(CHT)₁₄ counterpart (CHT = cyclohexanethiolate), with the critical role of aromatic ligand interactions identified by X-ray crystallography. The organic soluble Au₁₈(DMBT)₁₄ was successfully transferred into the aqueous phase by an amphiphilic polymer (Pluronic F127, abbrev. F127) wrapping method, producing Au₁₈-D@F127 nanoparticles [each containing a few NCs; Au₁₈-D is an abbreviation for Au₁₈(DMBT)₁₄] with a 10-fold enhancement in PL intensity, and similar results were also obtained for Au₁₈(CHT)₁₄. This method is broadly applicable to various NCs, rendering their water solubility and significantly enhancing the PL intensity of otherwise weakly emissive gold NCs. The exceptional antioxidation stability of Au₁₈(DMBT)₁₄ enables the application of Au₁₈-D@F127 NPs for the photocatalytic activation of persulfate ions and subsequent photodegradation of water pollutants efficiently.

An Au₃₆(S-tBu)₂₂ nanocluster (NC) is synthesized using the bulky tert-butyl thiol as the ligand. Single-crystal X-ray crystallography reveals that it has an Au₂₅ core which evolves from the Au₂₂ core in the previously reported Au₃₀(S-tBu)₁₈, and the Au₂₅ core is protected by longer staple-like surface motifs. The new Au₃₆ NC extends the members of the face-centered cubic structural evolution by adding an Au₃ triangle and an Au₄ tetrahedron unit. Additionally, it is found that Au₃₆ emits near-infrared photoluminescence at 863 nm with a quantum yield (QY) of 4.3%, which is five times larger than that of Au₃₀(S-tBu)₁₈-the closest neighbor in the structural evolution pattern. The higher QY of Au₃₆ is attributed to a larger radiative relaxation (k_r), resulting from the structural effect. Finally, we find that the longer staple motifs lead to enhanced stability of Au₃₆(S-tBu)₂₂ relative to Au₃₀(S-tBu)₁₈.

CO2 capture is critical to solving global warming. Amine-based solvents are extensively used to chemically absorb CO2. Thus, it is crucial to study the chemical absorption of CO2 by amine-based solvents to better understand and optimize CO2 capture processes. Here, we use quantum computing algorithms to quantify molecular vibrational energies and reaction pathways between CO2 and a simplified amine-based solvent model—NH3. Molecular vibrational properties are important to understanding kinetics of reactions. However, the molecule size correlates with the strength of anharmonicity effect on vibrational properties, which can be challenging to address using classical computing. Quantum computing can help enhance molecular vibrational calculations by including anharmonicity. We implement a variational quantum eigensolver (VQE) algorithm in a quantum simulator to calculate ground state vibrational energies of reactants and products of the CO2 and NH3 reaction. The VQE calculations yield ground vibrational energies of CO2 and NH3 with similar accuracy to classical computing. In the presence of hardware noise, Compact Heuristic for Chemistry (CHC) ansatz with shallower circuit depth performs better than Unitary Vibrational Coupled Cluster. The “Zero Noise Extrapolation” error-mitigation approach in combination with CHC ansatz improves the vibrational calculation accuracy. Excited vibrational states are accessed with quantum equation of motion method for CO2 and NH3. Using quantum Hartree–Fock (HF) embedding algorithm to calculate electronic energies, the corresponding reaction profile compares favorably with Coupled Cluster Singles and Doubles while being more accurate than HF. Our research showcases quantum computing applications in the study of CO2 capture reactions.