Ligand-induced dependence of charge transfer in nanotube-quantum dot heterostructures

Lithium vanadium oxide (Li1.1V3O8) thick porous electrodes with high rate capacity: utilization and evolution upon extended cycling elucidated via operando energy dispersive X-ray diffraction and continuum simulation

Thick electrode design and charge transport across electrode were probed via operando EDXRD and an expanded continuum model.

Deliberate Modification of Fe3O4 Anode Surface Chemistry: Impact on Electrochemistry

Fe₃O₄ nanoparticles (NPs) with an average size of 8-10 nm have been successfully functionalized with various surface-treatment agents to serve as model systems for probing surface chemistry-dependent electrochemistry of the resulting electrodes. The surface-treatment agents used for the functionalization of Fe₃O₄ anode materials were systematically varied to include aromatic or aliphatic structures: 4-mercaptobenzoic acid, benzoic acid (BA), 3-mercaptopropionic acid, and propionic acid (PA). Both structural and electrochemical characterizations have been used to systematically correlate the electrode functionality with the corresponding surface chemistry. Surface treatment with ligands led to better Fe₃O₄ dispersion, especially with the aromatic ligands. Electrochemistry was impacted where the PA- and BA-treated Fe₃O₄ systems without the -SH group demonstrated a higher rate capability than their thiol-containing counterparts and the pristine Fe₃O₄. Specifically, the PA system delivered the highest capacity and cycling stability among all samples tested. Notably, the aromatic BA system outperformed the aliphatic PA counterpart during extended cycling under high current density, due to the improved charge transfer and ion transport kinetics as well as better dispersion of Fe₃O₄ NPs, induced by the conjugated system. Our surface engineering of the Fe₃O₄ electrode presented herein, highlights the importance of modifying the structure and chemistry of surface-treatment agents as a plausible means of enhancing the interfacial charge transfer within metal oxide composite electrodes without hampering the resulting tap density of the resulting electrode.

Synthesis, properties, and formation mechanism of Mn-doped Zn2SiO4 nanowires and associated heterostructures

Charge transfer and energy transfer phenomena were observed and analyzed in heterostructure systems composed of CdSe QDs immobilized onto Mn-doped Zn₂SiO₄ nanowire host materials.

High-performance nanotube-enhanced perovskite photodetectors

Organic-inorganic perovskites have already shown a tremendous potential for low-cost light-harvesting devices. Yet, the relatively low carrier mobilities in bulk perovskites still prevent large-area devices with performances competing with state-of-the-art technologies. Here, we tackle this fundamental challenge by incorporating single-wall carbon nanotubes within a perovskite matrix by means of a simple two-step method in ambient air. Using this nano-engineered hybrid film, we demonstrate large-area photodetectors with responsivities up-to 13.8 A.W⁻¹ and a broad spectral response from 300 to 800 nm, indicating that photocurrent generation arises from the charge transfer from the perovskite matrix to the embedded nanotube network. As the nanotubes facilitate the carrier extraction, these photodetectors also show a fast response time of 10 ms. This is significantly faster than most of previous reports on perovskite-based photodetectors, including devices with much smaller photosensitive areas. This approach is also well-suited for large-scale production of other perovskite-based light-harvesting devices.