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Particulate matter (PM) found in the air is one of the major sources of pollution and air‐borne diseases. Therefore, it is imperative to examine the elemental concentration distribution of the PM to identify the pollutant sources. In this study, it has demonstrated the capabilities of micro‐particle‐induced X‐ray emission (micro‐PIXE) spectroscopy in quantitative analysis of air samples collected from the Old Delhi outdoor market and indoor locations in the Panjab University hostel in the winter months. A 2‐million electronvolts energetic scanning proton micro‐beam (diameter ≈1 µm²) is used in micro‐PIXE experiments generating high‐resolution elemental maps of different regions of interest (ROI). Micro‐PIXE along with the GeoPIXE analysis provides a non‐destructive, standard‐less, and ng/mg level‐sensitive tool for the investigation of elemental distributions and highlighting pixels, which correlates to specific concentration ratios between elements at ROIs, thereby enabling a comprehensive understanding of the source of each elemental particulate. Si, Ca, and K detected in indoor PM suggest the source to soil erosion and crop burning, while high S levels in outdoor PM are primarily associated with coal power plants. Additionally, Sc, Ti, Cr, Mn, and Zn are found in outdoor samples, while indoor locations also contained trace amounts of V, Co, and Cu. 

Metal halide perovskite (MHP) solar cells are promising aerospace power sources given their potential as inexpensive, lightweight, and resilient solar electricity generators. Herein, the intrinsic radiation tolerance of unencapsulated methylammonium lead iodide/chloride (CH3NH3PbI3-xClx) films was isolated. Spatially resolved photoluminescence (PL) spectroscopy and confocal microscopy revealed the fundamental defect physics through optical changes as films were irradiated with 4.5 MeV neutrons and 20 keV protons at fluences between 5×1010 and 1×1016 p+/cm2. As proton radiation increased beyond 1×1013 p+/cm2, defects formed in the film, causing both a decrease in photoluminescence intensity and a 30% increase in surface darkening. All proton irradiated films additionally exhibited continuous increase of energy bandgaps and decreasing charge recombination lifetimes with increasing proton fluences. These optical changes in the absorber layer precede performance declines detectable in standard current-voltage measurements of complete solar cell devices and therefore have the potential of serving as early indicators of radiation tolerance. 

We have investigated the concentration and correlation between the macro and micro-elements found in an herbal plant named Ocimum sanctum (Tulsi) leaf, using Particle-Induced X-ray Emission (PIXE) spectroscopy. The leaf area was analyzed with a 2 MeV scanning proton micro-beam with a spot size of ~ 1 square micrometer. This study is focused on exploring the correlation between the elemental maps generated using X-ray spectra with micro-PIXE. Two types of correlations i.e., elemental, and concentration-phase correlations were examined. The elemental maps are used to find the relation between the spatial distribution of the elements present in the scanned region while the correlation maps help in understanding which phase corresponds to the region of selected concentration ratios. All the elemental concentrations were determined with the detection limits in ng/mg. The analysis of macro-elements showed that the potassium concentration was highest and phosphorus exhibited the lowest concentration whereas iron was found to be highest in the category of trace or microelements. Moreover, broad-beam runs were also performed on the samples to examine the trend for elemental concentrations. 

We report on an examination of mobile ion concentration (N₀) in perovskite solar cells (PSCs) as a function of temperature and device architecture. 

Abstract Here, the radiation hardness of metal halide perovskite solar cells exposed to space conditions versus the effects of environmental degradation are assessed. The relative response of the constituent layers of the architecture to radiation is analyzed, revealing a general resilience of the structure when assessed across varying proton energy levels and fluences. However, despite the tolerance of the structure to irradiation, sensitivity to environmental degradation is observed during the transit of the device between the radiation and characterization facilities. Experimental evidence suggests the NiO_x/perovskite interface is particularly sensitive to the effects of humidity and/or temperature exposure, while the irradiation of the devices appears to induce thermally activated annealing: improving the solar cells upon radiation exposure. 

This paper discusses the in-situ characterization tools designed to assess radiation tolerance and elemental migration in perovskite materials. With the increasing use of perovskites in various technological applications, understanding their response to radiation exposure is paramount. Ion Beam Induced Charge (IBIC) emerges as a powerful tool for investigating the radiation tolerance of perovskites at the microscale. By employing focused ion beams, IBIC allows for the spatial mapping of charge carriers, offering insights into the material's electronic response to radiation-induced defects. This technique enables researchers to pinpoint areas of enhanced or suppressed charge collection, providing valuable information on the perovskite's intrinsic properties under irradiation. Rutherford Backscattering Spectrometry (RBS) complements the study by offering a quantitative analysis of elemental migration in perovskite materials. Through the precise measurement of backscattered ions, RBS provides a detailed understanding of the elemental composition and distribution within the perovskite lattice after radiation exposure. The integration of IBIC and RBS techniques in in-situ experiments enhances the comprehensive characterization of radiation effects on perovskites. 

ACIGS solar cells are exposed to targeted radiation to probe the front and back interfaces of the absorber to assess the impact of space environments on these systems. These data suggest ACIGS cells are more radiation‐hard than early CIGS devices likely due to the lower defect densities and more ideal interfaces in the ACIGS system. A combination ofJ–Vand external quantum efficiency measurements indicates some improvement in the performance of the device due to the effects of local heating in the dominant ionizing electronic energy loss regime of proton irradiation that anneal the upper CdS/ACIGS interface. However, nonionizing energy losses at the base of the solar cell also appear to inhibit minority carrier collection from the back of the cell at the ACIGS/Mo interface, which is discussed in terms of defect‐mediated changes in the doping profile, the Ga/Ga+In ratio, and impurity composition after proton irradiation. 

Mixed organic–inorganic halide perovskite-based solar cells have attracted interest in recent years due to their potential for both terrestrial and space applications. Analysis of interfaces is critical to predicting device behavior and optimizing device architectures. Most advanced tools to study buried interfaces are destructive in nature and can induce further degradation. Ion beam techniques, such as Rutherford backscattering spectrometry (RBS), is a useful non-destructive method to probe an elemental depth profile of multilayered perovskite solar cells (PSCs) as well as to study the inter-diffusion of various elemental species across interfaces. Additionally, PSCs are becoming viable candidates for space photovoltaic applications, and it is critical to investigate their radiation-induced degradation. RBS can be simultaneously utilized to analyze the radiation effects induced by He+ beam on the device, given their presence in space orbits. In the present work, a 2 MeV He+ beam was used to probe the evidence of elemental diffusion across PSC interfaces with architecture glass/ITO/SnO2/Cs0.05(MA0.17FA0.83)0.95Pb(I0.83Br0.17)3/spiro-OMeTAD/MoO3/Au. During the analysis, the device active area was exposed to an irradiation equivalent of up to 1.62 × 1015 He+/cm2, and yet, no measurable evidence (with a depth resolution ∼1 nm) of beam-induced ion migration was observed, implying high radiation tolerance of PSCs. On the other hand, aged PSCs exhibited indications of the movement of diverse elemental species, such as Au, Pb, In, Sn, Br, and I, in the active area of the device, which was quantified with the help of RBS.