Nanoscale

doi: 10.1039/D2NR90112Apmid: N/A

doi: 10.1039/D2NR90113Gpmid: N/A

doi: 10.1039/D2NR90114Epmid: N/A

Xia, Dong; Yu, Huayang; Xie, Huan; Huang, Peng; Menzel, Robert; Titirici, Maria Magdalena; Chai, Guoliang

doi: 10.1039/d2nr01900kpmid: 35635464

To mitigate excessively accumulated carbon dioxide (CO2) in the atmosphere and tackle the associated environmental concerns, green and effective approaches are necessary. The electrocatalytic CO2 reduction reaction (CO2RR) using sustainable electricity under benign reaction conditions represents a viable way to produce value-added and profitable chemicals. In this minireview, recent studies regarding unary Bi electrocatalysts and binary BiSn electrocatalysts are symmetrically categorized and reviewed, as they disclose high faradaic efficiencies toward the production of formate/formic acid, which has a relatively higher value of up to 0.50 $·per kg and has been widely used in the chemical and pharmaceutical industry. In particular, the preparation methodologies, electrocatalyst morphologies, catalytic performances and the corresponding mechanisms are comprehensively presented. The use of solid-state electrolytes showing high economic prospects for directly obtaining high-purity formic acid is highlighted. Finally, the remaining questions and challenges for CO2RR exploitations using Bi-related electrocatalysts are proposed, while perspectives and the corresponding strategies aiming to enhance their entire catalytic functionalities and boost their performance are provided.

Mitsui, Masaaki; Wada, Yuki; Kishii, Ryoto; Arima, Daichi; Niihori, Yoshiki

doi: 10.1039/d2nr00813kpmid: 35470826

In photoluminescence (PL) quenching and triplet fusion upconversion experiments with fluorescent organic-molecule quenchers, it was revealed that a rod-shaped, phosphine- and thiolate-protected biicosahedral Au25 cluster (a representative di-superatomic molecule) exhibits only phosphorescence, not fluorescence, at room temperature with an intersystem crossing quantum yield of almost 100%. By virtue of these photophysical properties, this cluster can be used as a triplet sensitizer that undergoes direct singlettriplet transitions in the near-infrared (NIR) region (730900 nm), inducing photon upconversion from NIR to visible light.

Binford, Trevor B.; Mapstone, Grace; Temprano, Israel; Forse, Alexander C.

doi: 10.1039/d2nr00748gpmid: 35615907

Supercapacitive swing adsorption (SSA) is a recently discovered electrochemically driven CO2 capture technology that promises significant efficiency improvements over traditional methods. A limitation of this approach is the relatively low CO2 adsorption capacity, and the underlying molecular mechanisms of SSA remain poorly understood, hindering optimization. Here we present a new device architecture for simultaneous electrochemical and gas-adsorption measurements, and use it to investigate the effects of charging protocols on SSA performance. We show that altering the voltage applied to charge the SSA device can significantly improve performance. Charging the gas-exposed electrode positively rather than negatively increases CO2 adsorption capacity and causes CO2 desorption rather than adsorption with charging. We also show that switching the voltage between positive and negative values further increases CO2 capacity. Previously proposed mechanisms of the SSA effect fail to explain these phenomena, so we present a new mechanism based on movement of CO2-derived species into and out of electrode micropores. Overall, this work advances our knowledge of electrochemical CO2 adsorption by supercapacitors, potentially leading to devices with increased uptake capacity and efficiency.

Fan, Chaoyu; Tang, Yonghua; Wang, Hao; Huang, Yifan; Xu, Fei; Yang, Yun; Huang, Yangyang; Rong, Weifeng; Lin, Youhui

doi: 10.1039/d2nr01213hpmid: 35621079

Inspired by the structures of enzymes, a fast and robust strategy for generating ZIF-90 metallo-nanozymes is presented. The ZnN coordination structure in ZIF-90 can closely imitate the catalytic center of a natural zinc-based hydrolase. As expected, ZIF-90 possesses potent hydrolase-mimicking activity, high stability and excellent recyclability.

Mario-Lpez, Andrea; Alvarez-Puebla, Ramon A.; Vaz, Beln; Correa-Duarte, Miguel A.; Prez-Lorenzo, Moiss

doi: 10.1039/d2nr00531jpmid: 35467676

Tear analysis has become an invaluable asset in clinical research in order to identify and quantify novel biomarkers for a wide array of conditions. The present work is intended to take this area of study one step further by implementing an innovative sensing platform through which exploration of low-molecular-weight compounds is conducted outperforming traditional analytical technologies. With this aim, carefully engineered plasmonic nanoassemblies have been synergistically combined with molecular-sieving materials giving rise to size-selective samplers with SERS detection capabilities. These architectures have been then integrated onto hydrogel-based contact lenses and tested in simulated tear fluids in order to evidence their operational features. Through this approach, a prolonged analyte accumulation can be realized, thus providing a competitive advantage in those scenarios where concentration of biomarkers is typically low or minimum sample volumes are not met. Additionally, quenching of metabolic flux and analyte extraction protocols can be circumvented, hence preventing the intrinsic physical and chemical interferences stemming from these procedures. The obtained results render these sensing platforms as promising medical devices, and constitute a great opportunity in order to expand the clinical toolkit in tear analysis.

Chen, Yuming; Gu, Jiayi; Liu, Yan; Xu, Ke; Song, Jie; Wang, Xueling; Yu, Dehong; Wu, Hao

doi: 10.1039/d1nr07921bpmid: 35587814

The study of drug delivery systems to the inner ear is a crucial but challenging field. The sensory organ (in the inner ear) is protected by the petrous bone labyrinth and the membranous labyrinth, both of which need to be overcome during the drug delivery process. The requirements for such a delivery system include small size, appropriate flexibility and biodegradability. DNA nanostructures, biomaterials that can arrange multiple functional components with nanometer precision, exhibit characteristics that are compatible with the requirements for inner ear drug delivery. Herein, we report the development of a novel inner ear drug delivery system based on epigallocatechin gallate (EGCG)-loaded tetrahedral DNA nanostructures (TDNs, EGCG@TDNs). The TDNs self-assembled via base-pairing of four single-stranded DNA constructs and EGCG was loaded into the TDNs through non-covalent interactions. Cy5-labeled TDNs (Cy5-TDNs) were significantly internalized by the House Ear Institute-Organ of Corti 1 cell line, and this endocytosis was energy-, clathrin-, and micropinocytosis-dependent. Cy5-TDNs penetrated the round window membrane (RWM) rapidly in vivo. Local application of EGCG@TDNs onto the RWM of guinea pigs in a single dose continuously released EGCG over 4 hours. Drug concentrations in the perilymph were significantly elevated compared with the administration of free EGCG at the same dose. EGCG@TDNs were found to have favorable biocompatibility and strongly affected the RSL3-induced down-regulation of GPX4 and the generation of reactive oxygen species, on the basis of 2′,7′-dichlorodihydrofluorescein diacetate staining. JC-1 staining suggested that EGCG@TDNs successfully reversed the decrease in mitochondrial membrane potential induced by RSL-3 in vitro and rescued cells from apoptosis, as demonstrated by the analysis of Annexin V-FITC/PI staining. Further functional studies showed that a locally administered single-dose of EGCG@TDNs effectively preserved spiral ganglion cells in C57/BL6 mice after noise-induced hearing loss. Hearing loss at 5.6 and 8 kHz frequencies was significantly attenuated when compared with the control EGCG formulation. Histological analyses indicated that the administration of TDNs and EGCG@TDNs did not induce local inflammatory responses. These favorable histological and functional effects resulting from the delivery of EGCG by TDNs through a local intratympanic injection suggest potential for therapeutic benefit in clinical applications.

Sim, Wei Jian; Nguyen, Mai Thanh; Huang, Zixuan; Kheawhom, Soorathep; Wattanakit, Chularat; Yonezawa, Tetsu

doi: 10.1039/d2nr01258hpmid: 35612908

Ironcobalt (FeCo) oxides dispersed on reduced graphene oxide (rGO) were synthesized from nitrate precursors at loading levels from 10 wt% to 60 wt%. These catalysts were tested in lab-scale zincair batteries (ZABs) at a high current density of 100 mA cm2 of the cathode area for the first time, cycling between 60 min of discharging and 60 min of charging. The optimum loading level for the best ZAB cycling performance was found to be 40 wt%, at which CoFe2O4 and CoO nanocrystals were detected. A discharge capacity of at least 90% was maintained for about 60 cycles with FeCo 40 wt%, demonstrating superior stability over amorphous FeCo oxides with FeCo 10 wt% despite similar performance at electrochemical tests. At a high current density of 100 mA cm2, OER catalytic activity was found to be the limiting factor in ZAB's cyclability. The discrepancies between the ORR/OER catalytic activities by electrochemical and battery cycling test results highlight the role and importance of rGO in improving electrical conductivity and activation of metal oxide electrocatalysts under high current density conditions. The difference of battery cycling test results from traditional electrochemical test results suggests that electrochemical tests conducted at low current densities may be inadequate in predicting practical battery cycling performance.