Hybrid bronzes: mixed-valence organic–inorganic metal oxides as a tunable material platform

Abstract

Hybrid bronzes are air/water-stable mixed-valence organic–inorganic metal oxides displaying tunable optoelectronic properties and high conductivity relevant for energy-related applications.

Controlling Electron Delocalization in Vanadium‐Based Hybrid Bronzes through Molecular Templation

“…Though hydrothermal syntheses afford single crystals that allow for precise structural determination of hybrid vanadium bronzes, we also sought a more rapid and facile synthetic protocol, similar to our report for molybdenum‐ and tungsten‐based hybrid bronzes [22] . This method would ideally be one in which vanadium oxide and organic precursors could be combined in water, under air, and at milder temperatures.…”

“…Furthermore, they often suffer from instability to moisture, electrochemical potential, other solvents, and elevated temperatures [17–21] . To meet these challenges, we have recently begun developing hybrid bronzes as a tunable air‐ and water‐stable material platform that supports variable charge‐carrier concentrations and high electronic conductivity within mixed‐valence inorganic metal‐oxide layers that alternate with ordered arrays of organic molecules that can direct structure and impart additional functionality [22] …”

Controlling Electron Delocalization in Vanadium‐Based Hybrid Bronzes through Molecular Templation

“…Though hydrothermal syntheses afford single crystals that allow for precise structural determination of hybrid vanadium bronzes, we also sought a more rapid and facile synthetic protocol, similar to our report for molybdenumand tungsten-based hybrid bronzes. [22] This method would ideally be one in which vanadium oxide and organic precursors could be combined in water, under air, and at milder temperatures. Since lower temperature and pressure did not readily allow for direct amine-based reduction of vanadium oxide, we first developed a mild reduction method to produce H x V 2 O 5 [48] using SnCl 2 as a reductant in acetic acid (see Supporting Information for details).…”

“…[17][18][19][20][21] To meet these challenges, we have recently begun developing hybrid bronzes as a tunable air-and water-stable material platform that supports variable charge-carrier concentrations and high electronic conductivity within mixed-valence inorganic metal-oxide layers that alternate with ordered arrays of organic molecules that can direct structure and impart additional functionality. [22] Mixed-valence inorganic metal oxides of the form A x MO y (A = cation; M=Mo, W, V, Nb) are broadly referred to as "bronzes" owing to their reflection of incident light by quasi-free electrons, yielding a metallic luster similar to that of the more well-known copper-tin alloy. The delocalized electrons are balanced in charge by either the intercalation of small cations, such as protons or alkali ions, or by oxygen vacancies.…”