Vanadium Cluster Neutrals Reacting with Water: Superatomic Features and Hydrogen Evolution in a Fishing Mode

Abstract

Hydrogen evolution reaction (HER) is known as the heart of various energy storage and conversation systems of renewable energy sources. Here we observe the cluster reactions of a light transition metal, vanadium, with water in a gas-phase flow tube reactor. While HER products of V1 and V2 were not observed, the effective HER of water on neutral V n (n ≥ 3) clusters reveals reasonable and size-dependent reactivity of the vanadium clusters. Superatomic features and reaction dynamics of V10, V13, and V16 are highlighted. Among the three typical superatoms, V10 and V16 exhibit an abnormal superatomic orbital energy level order, 1S|2S|1P|1D..., where the energy-reduced 2S orbital helps to accommodate the geometric structure and hence reinforce the cluster stability. In comparison, V13 bears a less symmetrical structure and reacts readily with water, allowing for recombination of a hydroxyl atom with an adsorbed hydrogen atom, akin to a fishing-mode HER process. The joint experimental and theoretical study on neutral V n clusters clarifies the availability of superatom chemistry for transition metals and appeals further development of cluster theory based on electronic cloud/orbital analysis instead of simply counting the valence electrons. Also, we provide insights into the HER mechanism of metal clusters and propose a strategy to design new materials for portable fuel cells of hydrogen energy.

Water Splitting by C60‐Supported Vanadium Single Atoms

“…In recent studies on the reaction between water and both cationic and neutral vanadium clusters, Zhang et al. found that three‐atom vanadium clusters, V 3 +/0 , can greatly reduce the energy barrier of the critical step towards effective H 2 release from a single water molecule compared to a single vanadium atom [8g, j] . This finding is consistent with infrared spectroscopic studies under quite similar experimental conditions of V + (H 2 O) n , which indicate that the water molecules on free V + , in particular for n =1, remain intact [12] .…”

Photochemistry and UV/vis spectroscopy of hydrated vanadium cations, V+(H2O)n, n = 1–41, a model system for photochemical hydrogen evolution

“…47 Water molecules in collisions with neutral and cationic vanadium clusters V n 0/+ were found by Luo and co-workers to undergo H 2 elimination and formation of V n O 0/+ . 48,49 In the present study, we re-investigate the photochemistry of V + (H 2 O) n , n = 1-4, using a tunable optical-parametric oscillator (OPO) system to extend both wavelength range and resolution and to increase sensitivity due to its high spectral radiation density. We then continue to clusters with up to 41 water molecules to learn more about the electronic and geometric structure in the cluster-size regime where thermally activated hydrogen evolution occurs.…”

“… 47 Water molecules in collisions with neutral and cationic vanadium clusters V n 0/+ were found by Luo and co-workers to undergo H 2 elimination and formation of V n O 0/+ . 48,49 …”

Unveiling the Mechanisms Ruling the Efficient Hydrogen Evolution Reaction with Mitrofanovite Pt3Te4

“…In particular, HER enables achieving ultrapure hydrogen. 1 − 5 Specifically, HER is the cathodic reaction in electrochemical water splitting (2H 2 O → 2H 2 + O 2 ). 1 , 2 , 5 Considering its crucial technological relevance, the identification of efficient electrocatalysts for HER with high activity, cheapness and long-term stability represents one of the most important open challenges in electrochemistry.…”

“… 1 − 5 Specifically, HER is the cathodic reaction in electrochemical water splitting (2H 2 O → 2H 2 + O 2 ). 1 , 2 , 5 Considering its crucial technological relevance, the identification of efficient electrocatalysts for HER with high activity, cheapness and long-term stability represents one of the most important open challenges in electrochemistry. 1 − 5 To date, Pt is generally assumed to be the state-of-the-art HER electrocatalyst, owing to its nearly zero overpotential, relatively low Tafel slope, and good stability.…”