Controlling the electrical conductance and in particular the occurrence of quantum interference in single-molecule junctions through gating effects, has potential for the realization of highperformance functional molecular devices. In this work, we used an electrochemically-gated, mechanically-controllable break junction technique to tune the electronic behaviour of thiophene-based molecular junctions that show destructive quantum interference (DQI) features. By varying the voltage applied to the electrochemical gate at room temperature, we

Despite the development of medical technology, cancer still remains a great threat to the survival of people all over the world. Photothermal therapy (PTT) is a minimally invasive method for selective photothermal ablation of cancer cells without damages to normal cells. Recently, copper chalcogenide semiconductors have emerged as a promising photothermal agent attributed to strong absorbance in the near-infrared (NIR) region and high photothermal conversion efficiency. An earlier study witnessed a rapid increase in their development for cancer therapy, including CuS, CuSe and CuTe nanocrystals. However, a barrier is that the minimum laser power intensity for effective PTT is still significantly higher than the conservative limit for human skin exposure. Improving the photothermal conversion efficiency and reducing the laser power density has become a direction for the development of PTT. Furthermore, in an effort to improve the therapeutic efficacy, many multimode therapeutic nanostuctures have been formulated by integrating the photothermal agents with antitumor drugs, photosensitizers, or radiosensitizers, resulting in a synergistic effect. Various functional materials also have been absorbed, attached, encapsulated, or coated on the photothermal nanostructures, including fluorescence, computed tomography, magnetic resonance imaging, realizing cancer diagnosis, tumor location, site-specific therapy, and evaluation of therapeutic responses via incorporation of diagnosis and treatment. In this Account, we present an overview of the NIR-responsive photothermal semiconductor nanomaterials for cancer theranostics with a focus on their design and functionalization based on our own work. Our group has developed a series of chalcogenides with greatly improved NIR photoabsorption as photothermal agents, allowing laser exposure within regulatory limits. We also investigated the photothermal bioapplications of hypotoxic oxides including WO, MoO, and RuO, expanding their applications into a new field of photothermal materials. Furthermore, considering a much more enhanced therapeutic effect of multifunctional nanoagents, our group elaborately designed many nanocomposites, such as core-shell nanoparticles of FeO@CuS and CuS@mSiO, based on the integration of photothermal agents with contrast agents or other anticancer medicines, achieving cancer theranostic and synergistic treatment. Ternary compound nanocrystals were also prepared with synthetic simplicity for multimodal imaging-guided therapy for cancer. This Account summarizes our past work, including the design and concept, synthesis, and characterization for in vitro and in vivo applications. Then, we analyzed the tendencies of the NIR-responsive photothermal semiconductor nanomaterials for clinical applications, highlighting their prospects and challenges. We believe that the photothermal technology from the NIR-responsive photothermal semiconductor nanomaterials would promote cancer theranostics to result in giant strides forward in the future.

A new generation of photothermal theranostic agents is developed based on Cu3BiS3 nanocrystals. A computed tomography imaging response and photothermal effect, as well as near-infrared fluorescence emission, can be simultaneously achieved through Cu3BiS3 nanocrystals rather than frequently used nanocomposites. These results provide some insight into the synergistic effect from bimetal sulphide semiconductor compounds for photothermal theragnosis therapy.

The experimental investigation of intermolecular charge transport in π‐conjugated materials is challenging. Herein, we describe the investigation of charge transport through intermolecular and intramolecular paths in single‐molecule and single‐stacking thiophene junctions by the mechanically controllable break junction (MCBJ) technique. We found that the ability for intermolecular charge transport through different single‐stacking junctions was approximately independent of the molecular structure, which contrasts with the strong length dependence of conductance in single‐molecule junctions with the same building blocks, and the dominant charge‐transport path of molecules with two anchors transited from an intramolecular to an intermolecular path when the degree of conjugation increased. An increase in conjugation further led to higher binding probability owing to the variation in binding energies, as supported by DFT calculations.