Selective etching mechanism of silicon oxide against silicon by hydrogen fluoride: a density functional theory study.

Selective etching of silicon oxide (SiO) against silicon (Si) using anhydrous hydrogen fluoride (HF) vapor has been used for semiconductor device fabrication. We studied the underlying mechanism of the selective etching by density functional theory (DFT) calculation. We constructed surface slab models of SiO or Si with different degrees of fluorination and simulated the four steps of fluorination.

Solid-state nitrogen-doped carbon nanoparticles with tunable emission prepared by a microwave-assisted method.

Tunable emissive solid-state carbon nanoparticles (CNPs) have been successfully synthesized by a facile synthesis through microwave irradiation. Modulating microwave interaction with the sample to generate abrupt localized heating is a long-term challenge to tailor the photoluminescence properties of CNPs. This study systematically revealed that the sample temperature through microwave irradiation plays a crucial role in controlling the photoluminescence properties over other reaction conditions, such as irradiation time and microwave duty cycle.

Correction: Solid-state nitrogen-doped carbon nanoparticles with tunable emission prepared by a microwave-assisted method.

[This corrects the article DOI: 10.1039/D1RA07290K.].

Effect of HSO/HO pre-treatment on electrochemical properties of exfoliated graphite prepared by an electro-exfoliation method.

The effect of pre-treating graphite sheets in a HSO/HO solution before electro-exfoliation is reported. It was revealed that the volume fraction of HSO to HO during pre-treatment could control the degree of exfoliation of the resulting exfoliated graphite (EG). X-ray diffraction (XRD), Raman, and Fourier transform infrared (FTIR) spectroscopy analyses have suggested that EG produced by first pre-treating the graphite sheet in HSO/HO solution with the HSO : HO volume fraction of 95 : 5 demonstrates the highest exfoliation degree.

Simultaneous ultraviolet and first near-infrared window absorption of luminescent carbon dots/PVA composite film.

Liquid Carbon Dots (CDs) were successfully synthesized by hydrothermal method using urea and citric acid as raw materials. TEM images confirmed that the CDs have a spherical shape with a homogeneous distribution. The as-prepared liquid CDs could absorb ultraviolet (UV) and first near infra-red (NIR) window simultaneously.