Virtual Simulation Guiding High-Risk Undergraduate Experiments about Chemical Synthesis of MoS₂ Monolayers via a Schlenk Line

Abstract

Recently, two-dimensional (2D) nanostructures, such as graphene and few-layer MoS 2 , have been applied to wide fields based on their intriguing performances, and they contribute to developments of clean energy, biomedicine, and environmental protection. The synthesis of 2D nanostructures involves chemistry, materials, and biologyassociated interdisciplinary knowledge. Nevertheless, desired strategies that can be comprehensively and safely achieved by undergraduates or academic trainees are largely restricted considering the uses of toxic and pyrophoric reagents, high-risk manipulation, expensive instruments, and a time-consuming test period. Herein, chemically fundamental experiments are integrated with scientific frontiers, achieving the development of undergraduate's experimental projects based on up-to-the-minute academic results. In order to promote the high-efficient study and eliminate the risks among our learners, the virtual simulation courses are well-integrated, and students can independently complete the synthesis of 2D MoS 2 nanomateirals without the face-to-face guidance of mentors. Significantly, several characteristics are equipped in this project: (1) Students can master the uses of oxygen-sensitive, moisture-sensitive reagents and skills for operating high-risk reactions via the virtual system; (2) Universal preparation approaches of 2D nanomaterials, based on the Schlenk technique, are presented; (3) Students' understanding of MoS 2 monolayer characterization, properties, and applications is remarkably increased. This project aims at inspiring students' understanding for scientific frontiers, improving their academic and innovative skills, as well as expanding their advanced perspective.

Cysteine-Induced Chirality Evolution of Molybdenum Disulfide Nanodots from a Bottom-Up Strategy

“…In the past two decades, two-dimensional (2D) nanomaterials with graphene-like structures have attracted great attention in chiral recognition, photocatalytic degradation, and hydrogen evolution reactions. , The preparation methods of layered transition metal disulfides (TMDs) have also been widely explored. − Similarly, in our previous study, lithium-ion intercalation and ultrasonic exfoliation were explored to synthesize 2D MoS 2 nanosheets. − However, using this top-down synthesis method to produce high-quality molybdenum disulfide nanomaterials is extremely challenging. ,− In addition, bottom-up strategies largely contribute to the synthesis of layered nanostructures from their elemental precursors. , Based on the developed synthesis routes, emerging structures, and properties were supposed to be involved in layered nanostructures for expanded applications. For instance, with the integration of benefits and potential application of chirality, chiral 2D nanomaterials have also been widely explored. − …”

Design and Exploration of Iron Salt-Catalyzed Synthesis of Chromene[2,3-b] Indoles as a Laboratory Experiment for Undergraduates

“…16 Compared to using the glovebox, it shows advantages of simpler equipment requirements, easier operation, and lower maintenance costs. 17 TLC is a popularly chromatographic separation technology and widely used to distinguish reagents and reaction byproducts and monitor reaction progress. 18 It is carried out through an extremely thin layer of a stationary phase (e.g., silica) coated on aluminum, plastic, or glass plates, and a mobile phase is used to facilitate the separation of compounds according to their polarity.…”

“…The Schlenk technique is a mature and widely used experimental technology for performing anhydrous and anaerobic operation, and can be used for inert-gas purging and evacuation/backfill for apparatus assembly, pressure-equalizing addition funnel use, and filtration . Compared to using the glovebox, it shows advantages of simpler equipment requirements, easier operation, and lower maintenance costs . TLC is a popularly chromatographic separation technology and widely used to distinguish reagents and reaction byproducts and monitor reaction progress .…”

Sensitive Detection of Trace Vitamin C via Enzyme-like Catalysis of S Defect-Rich Ultrathin 2D MoS2: Comprehensive Innovative Experiments on Two-Dimensional Materials for Undergraduates

“…More importantly, the frontier of science, such as enzyme catalysis and two-dimensional materials, is introduced into undergraduate experiments. Thus, integrating this experiment into undergraduate teaching can stimulate students to think about innovative detection methods, add to their’ scientific literacy, raise their comprehensive hands-on skills to a high level . In addition, cultivating students’ experimental skills and comprehensive problem-solving abilities through an integrated research project is an effective method and approach. − …”

“…Thus, integrating this experiment into undergraduate teaching can stimulate students to think about innovative detection methods, add to their' scientific literacy, raise their comprehensive hands-on skills to a high level. 22 In addition, cultivating students' experimental skills and comprehensive problem-solving abilities through an integrated research project is an effective method and approach. 23−26 ■ EXPERIMENTAL SECTION Usually, this experiment is introduced in the seventh semester of an undergraduate course of study.…”