Organization of Organic Molecules with Inorganic Nanoparticles: Hybrid Nanodiodes

Abstract

A monolayer of inorganic nanoparticles and a monolayer of organic molecules have been electrostatically assembled in sequence. Such assemblies or organizations exhibit electrical rectification. When the sequence of the organization is reversed, the direction of rectification becomes opposite. In both n‐type ZnO/organic and organic/n‐ZnO assemblies, electron flow is favorable from the n‐ZnO nanoparticle to the (electron‐accepting) organic molecule. While the individual components do not show any rectification, substitutes of the organic molecule tune electrical rectification. Junctions between a p‐type ZnO nanoparticle and an electron‐donating metal phthalocyanine favor current flow in the nanoparticle‐to‐phthalocyanine direction. The rectification in a junction between a nanoparticle and an organic molecule is due to the parity between free carriers in the former component and the type of carrier‐accepting nature in the latter one. By observing electrical rectification with the tip of a scanning tunneling microscope, organic/inorganic hybrid nanodiodes or rectifiers on the molecular/nanoscale have been established.

SnO­2 Tailored by CuO for Improved CH4 Sensing at Low Temperature

“…This improved response and electrical measurement as seen in Figure point to the significant role of surface and interfaces formed between CuO and SnO 2 . Similar role of interfaces has been discussed in literatures . They modulate electronic states and influence physiochemical properties.…”

“…Similar role of interfaces has been discussed in literatures. [34,35] They modulate electronic states and influence physiochemical properties. In general, individual n-p junction creates a depletion layer which is in excess of chemisorbed based depletion in SnO 2 .…”

Molecular Electronics: Effect of External Electric Field

“…Theoretical approaches based on the equation of motion method [100] or Fock space formalism [101] have also begun to be appear to gain understanding of this regime. Although, we have discussed mainly about one of the technologically useful non-linear phenomena, namely, Negative differential resistance, other phenomena such as multistability and hysteresis, which arise out of structural changes in a molecule during transport together with inelastic processes due to interactions at different energy and length scales in organic, inorganic or hybrid systems still remain the subjects of active current research [102,103,104,105].…”

ZnO nanorod/nickel phthalocyanine hierarchical hetero-nanostructures with superior visible light photocatalytic properties assisted by H2O2

“…In order to remove the dyes from the aqueous environment, various methods have been explored, such as photocatalysis, adsorption, electrochemical degradation, acidication, etc. In order to overcome these drawbacks, efforts have been made via combination ZnO with other components including inorganic or organic semiconductor, noble metals, and grapheme et al [11][12][13][14] Owing to the appropriate redox properties for the sensitization of large band-gap semiconductors and the thermal stability, metal phthalocyanine (MPc) have received signicant attention for advanced applications in dye-sensitized solar cells, gas sensors and molecular electronic devices. [2][3][4] As an important wide and direct band-gap semiconductor, ZnO has been deemed to be an efficient photocatalyst because of its high catalytic efficiency, low cost, and environmental sustainability.…”

“…[8][9][10] The rapid recombination of photogenerated electron-hole pairs formed in photocatalytic processes is also a major obstacle for increasing the photocatalytic efficiency of ZnO. In order to overcome these drawbacks, efforts have been made via combination ZnO with other components including inorganic or organic semiconductor, noble metals, and grapheme et al [11][12][13][14] Owing to the appropriate redox properties for the sensitization of large band-gap semiconductors and the thermal stability, metal phthalocyanine (MPc) have received signicant attention for advanced applications in dye-sensitized solar cells, gas sensors and molecular electronic devices. [15][16][17][18][19][20] More recently, it has been demonstrated that MPc could hinder the charge recombination and improve the photocatalytic efficiency.…”