Henan Normal University

About: Henan Normal University is a education organization based out in Xinxiang, China. It is known for research contribution in the topics: Catalysis & Ionic liquid. The organization has 10863 authors who have published 11077 publications receiving 166773 citations.

Monolayer GeS as a potential candidate for NO2 gas sensors and capturers

Abstract: The gas sensing properties of single-layer GeS have been studied by performing density functional theory (DFT) calculations, and the present results demonstrate that monolayer GeS exhibits high selectivity and sensitivity toward NO2 molecules and short recovery time, coupled with a strong anisotropic transport feature. Moreover, applying biaxial strains and electric fields could effectively modulate the capture and release of gaseous NO2. Further calculations indicate that oxygen atoms and water molecules decorated on GeS hardly affect the superb selectivity toward NO2 against the other gases. The presence of an S-vacancy on the GeS monolayer greatly promotes the adsorption of NO2, facilitating molecular dissociation. The underlying mechanism is also elaborated at the level of electronic structures. The present findings make GeS monolayers potential materials for NO2 gas sensors and capturers in future applications.

Simultaneous Measurement of the Refractive Index and Temperature Based on Microdisk Resonator With Two Whispering-Gallery Modes

Abstract: In this paper, a microdisk resonator with two whispering-gallery modes (WGMs) is proposed for label-free biochemical sensing. According to the transmission responses of the two WGMs with different coupling gaps, there is the critical coupling status for the WGM (0, 36) while there is no critical coupling status for the WGM (1, 28). For the WGMs (0, 36) and (1, 28), the refractive index (RI) sensitivities of 45.8821 and 72.9402 nm/RIU are obtained, and the corresponding RI detection limits (DLs) of 8.5902 × 10 -4 and 1.9228 × 10 -3 RIU are achieved, respectively. Moreover, the proposed sensor also has the temperature sensitivities of 0.0730 and 0.0703 nm/K, which correspond to the temperature DLs of 0.1631 and 0.6263 K, respectively. By constructing a characteristic matrix, it is demonstrated that simultaneous measurement of the RI and temperature can be achieved.

d-Orbital steered active sites through ligand editing on heterometal imidazole frameworks for rechargeable zinc-air battery.

Abstract: The implementation of pristine metal-organic frameworks as air electrode may spark fresh vitality to rechargeable zinc-air batteries, but successful employment is rare due to the challenges in regulating their electronic states and structural porosity. Here we conquer these issues by incorporating ligand vacancies and hierarchical pores into cobalt-zinc heterometal imidazole frameworks. Systematic characterization and theoretical modeling disclose that the ligand editing eases surmountable energy barrier for *OH deprotonation by its efficacy to steer metal d-orbital electron occupancy. As a stride forward, the selected cobalt-zinc heterometallic alliance lifts the energy level of unsaturated d-orbitals and optimizes their adsorption/desorption process with oxygenated intermediates. With these merits, cobalt-zinc heterometal imidazole frameworks, as a conceptually unique electrode, empowers zinc-air battery with a discharge-charge voltage gap of 0.8 V and a cyclability of 1250 h at 15 mA cm–2, outperforming the noble-metal benchmarks. Low intrinsic activity and accessibility of active sites limit the application of metal-organic framework as catalyst for Zn-air battery. Here, authors present a cation substitution strategy to regulate the electronic state of metal sites and modify its porosity, which enables battery operation.