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A novel strategy for the improvement in the sensing performance of p-type NiO is developed by employing the unique functional properties of self-assembled monolayers. Specifically, hole concentration near the surface of NiO nanowires (NWs) is modulated by terminal epoxy groups of the organosilane. This modulation leads to the increase in electron transfer from reducing gases to NWs surface. As a result, SAM-functionalized sensors showed 9-times higher response at low-temperature as compared to bare NiO NWs.

Scientometrics and bibliometrics, the subfields of library and information science, deal with the quantity and quality of research outputs. Currently, various scientometric indices are being used to quantify and compare research outputs. The most widely known is the h-index. However, this index and its derivatives suffer from dependence on the mere count of a scholar's highly cited publications. To remedy this deficiency, we developed a novel index, the Universal Research Index (UR-Index) (https://usern2021.github.io/UR-Index/) by which every single publication has its own impact on the total score. We developed this index by surveying international top 1 % cited scientists in various disciplines and included additional component variables such as publication type, leading role of a scholar, co-author count, and source metrics to this scientometric index. We acknowledge that unconscious biases built into the component variables included in the UR-Index might put research from specific groups at a disadvantage, thus continued efforts to improve equitable scholarly impact in science and academia are encouraged.

The inspiration behind this work is to show the importance of tailoring metal oxide (MOX) nanowires with suitable self-assembled monolayers (SAMs) for the development of highly efficient, selective, and low power consuming chemical sensors. We showed that the methyl (-CH3) terminated-ZnO nanowires exhibit improved sensing performance toward acetone at 250 °C. The origin of enhancement in the sensor response is found to be the intermolecular interactions between SAM methyl (-CH3) and acetone carbonyl (CO) groups, while weak methyl-methyl interactions between the SAM and acetone molecules participate in enhancing sensor selectivity. Not only the response, but the ability of the sensor to discriminate acetone molecules is also improved after functionalization. Indeed, the functionalized sensor exhibits a detectable response even with shorter exposure times. Moreover, as compared to the literature concerning different sensor structures (no report is available on tetraethyl orthosilicate (TEOS) functionalized MOX nanowire based chemical sensors), TEOS functionalized sensors exhibit superior performance at relatively lower operating temperatures. Consequently, in contrast to other nanowire modification strategies such as metal-particle decorated MOX nanowires, the SAM functionalization strategy has the greatest potential to develop future high performance chemical sensor devices not only for acetone but also for other important analytes such as environmental pollutants.

The presence of surface defects, such as epoxy and carbonyl groups, is known to control the charge-carrier transport in graphene oxide (GO). In addition, these surface entities also provide an opportunity to synthesize novel hybrid (NH) materials via chemical bonding. These hybrid materials are particularly interesting for sensing as they offer novel properties like larger surface area and improved physical/chemical properties. Herein, we are proposing a novel SiO2@GO-NH based room-temperature (RT) ethanol sensor. The NH is realized from solution-route by following the sol-gel chemistry of tetraethyl orthosilicate. The attachment of SiO2 with the GO network occurs via the formation of Si-O-C bonds, which also leads to the reduction in the atomic percentage of electron-withdrawing groups. This reduction results in the improvement in electron charge transport in GO, which leads to the RT detection of ethanol. Specifically, the charge transport in NH is found to be dominated by a field-driven temperature-independent 2D variable-range hopping mechanism. While the ethanol sensing mechanism is found to be governed by two processes, i.e., via direct interaction of ethanol with NH and interaction with chemisorbed oxygen ions on the Pt/Si@GO-NH interface. Detailed observations reveal that the SiO2-GO NH has great potential to be used as a biomarker for food quality control.