Machine learning recognition of hybrid lead halide perovskites and perovskite-related structures from X-ray diffraction patterns.

Identification of crystal structures is a crucial stage in the exploration of novel functional materials. This procedure is usually time-consuming and can be false-positive or false-negative. This necessitates a significant level of expert proficiency in the field of crystallography and, especially, requires deep experience in perovskite-related structures of hybrid perovskites.

Long-Term Characterization of Oxidation Processes in Graphitic Carbon Nitride Photocatalyst Materials via Electron Paramagnetic Resonance Spectroscopy.

Graphitic carbon nitride (gCN) materials have been shown to efficiently perform light-induced water splitting, carbon dioxide reduction, and environmental remediation in a cost-effective way. However, gCN suffers from rapid charge-carrier recombination, inefficient light absorption, and poor long-term stability which greatly hinders photocatalytic performance. To determine the underlying catalytic mechanisms and overall contributions that will improve performance, the electronic structure of gCN materials has been investigated using electron paramagnetic resonance (EPR) spectroscopy.

Fast Recombination of Charge-Transfer State in Organic Photovoltaic Composite of P3HT and Semiconducting Carbon Nanotubes Is the Reason for Its Poor Photovoltaic Performance.

Although the photovoltaic performance of the composite of poly-3-hexylthiophene (P3HT) with semiconducting single-walled carbon nanotubes (s-SWCNT) is promising, the short-circuit current density is much lower than that for typical polymer/fullerene composites. Out-of-phase electron spin echo (ESE) technique with laser excitation of the P3HT/s-SWCNT composite was used to clarify the origin of the poor photogeneration of free charges. The appearance of out-of-phase ESE signal is a solid proof that the charge-transfer state of P3HT/s-SWCNT is formed upon photoexcitation and the electron spins of P3HT and s-SWCNT are correlated.

One-Pot Synthesis of 2--Naphtho[2,3-]thiophene-4,9-diones via Cyclization of 2-(-Ethynyl)-1,4-naphthoquinones with NaSO.

The concise and efficient one-pot synthesis of 2--naphtho[2,3-]thiophene-4,9-diones from 2-bromo-1,4-naphthoquinone and alkynes has been developed. The reaction proceeds through the formation of 2-(-ethynyl)-1,4-naphthoquinones, which undergo transformation with NaSO to 2--naphtho[2,3-]thiophene-4,9-diones via C-H sulfuration, accompanied by the formation of the aromatic Bunte salt, followed by its air oxidation and 5-endo-dig cyclization. The protocol is characterized by simplicity, good tolerance for functional groups, relatively mild conditions, and commercially available starting compounds.