This study details the efforts taken in remotely teaching a large organic chemistry lecture course in the midst of the recent COVID-19 pandemic. The course lectures were taught synchronously via Zoom and student feedback was gathered regarding effective teaching strategies and assessment tools in a remote course setting. The precourse and midcourse surveys also provided insight into challenges and time commitment issues that students are facing when learning in this new situation. We highlight the instructor’s experience combined with student perspectives to tackle this situation moving forward. We hope that this work can assist faculty in remotely teaching their chemistry courses, and contribute to the information that is being collected globally regarding remote learning in light of the recent events.

Numerous online resources provide a variety of content for a wide range of STEM topics; however, they tend to function as isolated tidbits that provide content-specific knowledge. Application-based science education videosaddress the overlooked issue of concept to application by implementing experimental components in their videos and fostering connections with everyday applications. We utilized the Journal of Visualized Experiments (JoVE) peer-reviewed science education videos as homework assignments to supplement lectures on the topics of enthalpy, entropy, rate laws, and Le Châtelier’s principle in a second-term general chemistry course. Student learning was assessed through the analysis of pre- and post-video conceptual quizzes, and value surveys were also conducted to gather student feedback about the videos. Our investigation shows that using these videos in the course significantly improved student learning and reinforced conceptual understanding for important foundational concepts, and these results hold even for students who did not feel positively toward the videos.

The synthesis of small boron oxide nanoparticles (NPs) is reported. A sonochemical approach in the presence of a capping agent was employed to produce approximately 4-5-nm-sized BO NPs, including the B isotopically enriched form. The morphology and composition of the NPs were established using transmission electron microscopy and diffraction, respectively. X-ray photoelectron and Fourier transform infrared spectroscopies provided information about surface functionalization of the BO NPs, which can be further modified through a facile, one-step ligand-exchange process. The toxicity of the synthesized NPs was investigated in Chinese hamster ovarian cells, indicating that these systems were nontoxic up to 1.7 mM concentrations.

The COVID-19 pandemic has forever changed the world, how people interact, and the way business is conducted. Higher education is no exception; as institutions quickly shifted to remote teaching in Spring 2020, many faculty needed to support student learning in ways that were new to them.

We report our discovery of utilizing perhydroxylated dodecaborate clusters ([B12(OH)12]2-) as a molecular cross-linker to generate a hybrid tungsten oxide material. The reaction of [B12(OH)12]2- with WCl6, followed by subsequent...

We report 1−2 unit-cell-thick CaF 2 nanosheets, which can be converted topochemically into LaF 3−2x O x nanosheets that scroll spontaneously. The formation of CaF 2 nanosheets is achieved through interlayer confinement and templating within CaSi 2 during reaction with aqueous HF. The structure and morphology of these nanosheets are characterized by HRTEM, AFM, and powder XRD. Solid-state MAS and solution 19 F NMR spectroscopies provide further information about interstitial fluoride sites within CaF 2 nanosheets as well as help identify side products of the CaSi 2 + HF reaction. CaF 2 nanosheets react with lanthanide salts at room temperature to yield nanostructured hexagonal LnF 3 (Ln = Ce, Pr, Nd, Sm, Eu), orthorhombic LnF 3 (Ln = Gd, Dy, Ho, Er, Yb), and cubic YbF 3−x products. Furthermore, the reaction of CaF 2 nanosheets with lanthanum salts is unique in producing LaF 3−2x O x . The evidence for this composition includes powder XRD, EDS, XPS, and 19 F NMR data. The structure of LaF 3−2x O x differs from hexagonal LaF 3 only in the replacement of two fluorides by one oxygen. While this topochemical transformation preserves the two-dimensional morphology it also causes lattice strain that initiates scrolling. The resulting product consists of remarkable ∼20 × 5 nm scroll-like tubes of LaF 3−2x O x that are unique among metal fluoride materials. These results demonstrate novel metal fluoride nanochemistry and a new scrolling mechanism.

Metal oxides are ubiquitous in our daily lives because they are robust and possess versatile electrochemical properties. Despite their popularity, these materials present limitations with respect to effective large-scale implementation. Recently, there has been growing interest in creating hybrid metal oxides to tailor the morphology and properties of these materials. From this perspective, we highlight several recent developments in cross-linked hybrid metal oxides, focusing on chemical cross-linking techniques to enrich their properties. We discuss future directions of this crosslinking approach that could enable further manipulation of these materials.

We describe the top-down nanostructuring of a metal boride using SrB as an example. To accomplish this transformation, we demonstrate (1) the direct lithiation of a metal boride using n-butyllithium and then (2) the reactive disassembly of Li-SrB into nanoparticles using water. The identity of the Li-SrB intermediate, a mixture of LiB, LiSrB, and SrB phases, was established by powder X-ray diffraction (PXRD), solid-state B andLi NMR, transmission electron microscopy, selected-area electron diffraction, and scanning electron microscopy. The necessary 2Li/Sr substitution is enabled by cation mobility within the hexaboride lattice. The subsequent reaction with water results in LiB decomposition and the release of <100 nm SrB nanoparticles, which were characterized by PXRD, solid-state B andLi NMR, and high-resolution TEM. This chemistry opens new solution-based modification and processing options for metal borides.