Water-Based Synthesis of Copper Chalcogenide Structures and Their Photodynamic Immunomodulatory Activities on Mammalian Macrophages

Generation of novel and versatile immunomodulatory agents that could suppress excessive inflammation has been crucial to fight against chronic inflammatory and autoimmune disorders. Immunomodulatory agents regulate the function of immune system cells to manage their activities. Current therapy regimens for the inflammatory and autoimmune disorders rely on immunomodulatory drug molecules but they are also associated with unwanted and severe side effects. In order to prevent the side effects associated with drug molecules, the field should generate novel immunomodulatory drug candidates and further test them. Moreover, the generation of photodynamic immunomodulatory molecules would also decrease possible side effects. Photodynamic activation enables specific and localized activation of the active ingredients upon exposure to a certain wavelength of light. In our study, we generated copper-based chalcogenide structures in gel and nanoparticle form by using a water-based method so that they are more biocompatible.After their chemical characterization, they were tested on mammalian macrophages in vitro. Our results suggest that these molecules were anti-inflammatory in dark conditions and their anti-inflammatory potentials significantly increased upon xenon light treatment. We are presenting novel photodynamic immunomodulatory agents that can be used to suppress excessive inflammation in disease conditions that have been associated with excessive inflammation.

Graphene-Based Hybrid Functional Materials

Graphene is a 2D material combining numerous outstanding physical properties, including high flexibility and strength, extremely high thermal conductivity and electron mobility, transparency, etc., which make it a unique testbed to explore fundamental physical phenomena. Such physical properties can be further tuned by combining graphene with other nanomaterials or (macro)molecules to form hybrid functional materials, which by design can display not only the properties of the individual components but also exhibit new properties and enhanced characteristics arising from the synergic interaction of the components. The implementation of the hybrid approach to graphene also allows boosting the performances in a multitude of technological applications. This review reports the hybrids formed by graphene combined with other low-dimensional nanomaterials of diverse dimensionality (0D, 1D, and 2D) and (macro)molecules, with emphasis on the synthetic methods. The most important applications of these hybrids in the fields of sensing, water purification, energy storage, biomedical, (photo)catalysis, and opto(electronics) are also reviewed, with a special focus on the superior performances of these hybrids compared to the individual, nonhybridized components.

Alkylamine-Integrated Metal-Organic Framework-Based Waveguide Sensors for Efficient Detection of Carbon Dioxide from Humid Gas Streams

Metal-organic framework (MOF)-based chemical sensors have recently been demonstrated to be highly selective, sensitive, and reversible for CO₂ sensing across a range of platforms including optical fiber and surface acoustic wave-based sensors. However, interference of water molecules is a primary issue in CO₂ sensing systems based upon MOF layers due to cross-sensitivity, stability of MOF-based materials in humid conditions, and associated baseline drift over the lifetime of sensors. Herein, we develop a simple approach of alleviating the negative effect of water vapor to the optical fiber sensor by using alkylamine (i.e., oleylamine) to form a protective hydrophobic layer on the surface of MOFs for improving water stability. Alkylamine-modification of a MOF-coated optical fiber sensor provides a reversible and stable sensing response to a wide range of CO₂ concentrations while also enhancing the CO₂ sensitivity of the sensor under wet conditions. The FT-IR and breakthrough studies on the oleylamine-modified MOF confirm that the water vapor does not adversely impact the intrinsic CO₂ sorption capacities. Thus, this simple stratrgy for enhancing the CO₂/H₂O selectivity in the MOF sorbent could also be useful for improving CO₂ capture/separation performance in flue gas stream.

A novel and cost effective CZTS hole transport material applied in perovskite solar cells

CZTS nano-particles are synthesized under ambient condition and applied as low-cost and sustainable inorganic HTM in Perovskite solar cells.

Cu2ZnSnS4/MoS2-Reduced Graphene Oxide Heterostructure: Nanoscale Interfacial Contact and Enhanced Photocatalytic Hydrogen Generation

Hydrogen generation from water using noble metal-free photocatalysts presents a promising platform for renewable and sustainable energy. Copper-based chalcogenides of earth-abundant elements, especially Cu₂ZnSnS₄ (CZTS), have recently arisen as a low-cost and environment-friendly material for photovoltaics and photocatalysis. Herein, we report a new heterostructure consisting of CZTS nanoparticles anchored onto a MoS₂-reduced graphene oxide (rGO) hybrid. Using a facile two-step method, CZTS nanoparticles were in situ grown on the surface of MoS₂-rGO hybrid, which generated high density of nanoscale interfacial contact between CZTS and MoS₂-rGO hybrid. The photoexcited electrons of CZTS can be readily transported to MoS₂ through rGO backbone, reducing the electron-hole pair recombination. In photocatalytic hydrogen generation under visible light irradiation, the presence of MoS₂-rGO hybrids enhanced the hydrogen production rate of CZTS by 320%, which can be attributed to the synergetic effect of increased charge separation by rGO and more catalytically active sites from MoS₂. Furthermore, this CZTS/MoS₂-rGO heterostructure showed much higher photocatalytic activity than both Au and Pt nanoparticle-decorated CZTS (Au/CZTS and Pt/CZTS) photocatalysts, indicating the MoS₂-rGO hybrid is a better co-catalyst for photocatalytic hydrogen generation than the precious metal. The CZTS/MoS₂-rGO system also demonstrated stable photocatalytic activity for a continuous 20 h reaction.