The advent of halide perovskite permitted significant progress in the field of III generation photovoltaics (PV), demonstrating a rapid growth of power conversion efficiency (PCE) up to 25.5% during the last decade. [1] This is mainly due to the peculiar properties of halide perovskites for photoelectric conversion: strong absorption in the visible region of the solar light spectrum, [2] defect tolerance, [3] big diffusion lengths of the charge carriers (>1 mm), [4] and tunability of the bandgap in the wide range (from 1.9 to 3.1 eV). [5] The improvement of perovskite solar cell (PSC) performance has been mainly driven by solution processing of the absorber films that allows simplifying the device fabrication at low temperature [6,7] by using various methods for the perovskite crystallization [8] and the control of morphology. [9] The cost-effective solution-based fabrication of the PSCs could be realized with various printing methods such as blade coating, [10,11] inkjet printing, [12] and slot-die, [13] which do not require the use of high vacuum and provide high throughput speed of production. Among the printing methods, the slot-die coating was considered as one of the most promising for upscale of the PSCs in sheetto-sheet and roll-to-roll fabrication. [13][14][15] This method of wet coating provides a high speed and large-area fabrication, [16] good film thickness control, highly uniform coating, and enables the effective ink consumption without materials loss during the deposition. [17,18] The upscaling of PSCs from lab-scale to large modules with an application of printing methods is a complex technological process that requires special fabrication conditions, including

Nanowires represent numerous opportunities for nanoelectronics and sensorics, while metal contact fabrication makes the device development rather challenging. Here, we demonstrate that silicon (Si) nanowires deposited on interdigital metal contacts via simple drop casting exhibit an abrupt increase in conductivity upon exposure to ammonia vapors and aqueous solutions due to adsorption of the analyte species. To reduce the noise of the DC resistance measurements lacking ohmic conductivity, we exploit electronic impedance spectroscopy. The resistive response is found to be dependent on the ammonia content in vapor and liquid matter. The results demonstrate a detection limit of 4 μmol•L −1 (80 ppb), a sensitivity of 0.2% μmol −1 •l (0.01%•ppb −1 ), and applicability for the low-concentration detection of up to 400 μmol•L −1 (8 ppm) ammonia in aqueous solutions both directly and indirectly with a response rate of up to 0.43%•s −1 and a recovery rate of 0.31%•s −1 and show selectivity to oxidizing species. Thus, we demonstrate that the use of semiconductor nanowires in adsorption sensorics does not require the fabrication of ohmic contacts and present a simple fabrication protocol perspective for the development of highly sensitive room-temperature multi-environment sensors.

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The impact of interface states on the quantum efficiency of a‐Si:H/c‐Si solar cells based on Si wires is studied using simulation and experimental measurements. The key role of the Si wire geometry for sensitivity of quantum efficiency to interface states on the sidewall is demonstrated. A decrease in Si wire diameter leads to enhanced recombination at the radial interface due to full inversion of the wire. Structures based on n‐Si wires with diameter of 0.5 and 1.5 μm and doping level of 2 × 1015 cm−3 fabricated using a combination of latex sphere lithography and cryogenic dry etching exhibit similar values of open‐circuit voltage (0.5 V) and strong differences for quantum efficiency spectra. For the structures based on Si wires with a radius (0.25 μm) smaller than the space‐charge region (0.6 μm) losses related to interface recombination leads to decrease in the quantum efficiency in the short‐wavelength region. The recombination losses may be reduced for Si wires with a radius exceeding the space charge region in silicon. In case of Si with a doping level of 1015–1016 cm−3, which is used for solar cells, the diameter of the wires should be above 1 μm.

Carbon monoxide and ammonia are inorganic agents found both in nature and in the human body, which is of great interest for modern sensing. First, in concentrations of the order of 1 ppm agents are produced by human and can be markers of changes in human health. Second, at concentrations of the order of 100 ppm, carbon monoxide and ammonia are toxic and hazardous. This work is aimed at fabrication and study of precise, technological and relatively cheap sensors compatible with a gas and liquid medium for CO and NH3 detection, respectively.