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Metal halide perovskites have been the subject of intense theoretical and experimental research in recent years, due to their huge potential over their silicon-based counterparts for tunable optoelectronic applications in hightech device innovation. The current best perovskite for solar cell applications, with a power conversion efficiency of 22%, methylammonium lead iodide (CH 3 NH 3 PbI 3), is toxic due to the presence of lead and is therefore harmful in solar cell applications despite its low concentration in solar cells. Hence, research exploits are geared towards perovskites without lead. Unfortunately, this has taken back the gains in PCEs by about 70%, and a lot is being done for improvement. In this paper, a new approach to these studies is introduced by performing Monte Carlo simulations of ion-beam sputtering of lead and tin perovskites, as well as other promising candidate materials, in order to throw some light on their potentials for higher efficiencies in photovoltaic applications. The sputtering characteristics of six promising perovskites, including lead perovskite and lead-substituted perovskites, were compared. The results showed a remarkable exhibition of similar sputtering characteristics of linear projected ion range for Pb and Sn, with a maximum sputter yield around 78°ion incidence. The results also indicated a correspondence between the sputtering characteristics and PCE.

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The risk of natural terrestrial radioactivity on human health is often underestimated, and environmental safety awareness is necessary. Hence, this study aims to assess natural sources of gamma radiation emitter in coastal urban-environment using the radiometric technique. The dosage of gamma radiation from a parent radionuclide such as Uranium-238 (238U), Thorium-232 (232Th) and Potassium-40 (40K) and were measured using portable gamma spectroscopy. The result showed that the measured value of 238U activity was between 10.81 $$\pm$$ ± 0.69 and 46.31 $$\pm$$ ± 1.43 Bqkg−1. The mean value was estimated to be 35.44 $$\pm$$ ± 0.97 Bqkg−1 which is slightly higher than the world average. Meanwhile, 232Th activity ranges from 28.42 $$\pm$$ ± 1.12 to 69.43 $$\pm$$ ± 1.76 Bqkg−1 with the calculated mean value of 92.57 $$\pm$$ ± 1.17 Bqkg−1 while 40K activity ranged between 31.30 ± 1.32 and 328.65 ± 2.32 Bqkg−1 with the estimated mean 137.59 $$\pm$$ ± 2.42 Bqkg−1. Radiological parameters such as radium equivalent (Req), internal hazard (Hint) and external hazard (Hext) assessment were in the range of 66.00 Bqkg−1 to 141.76 Bqkg−1, 0.232 to 0.452 and 0.178 to 0.383, respectively. The measured values of gamma dose-rates ranged between 54.283 ± 0.78 and 117.531 ± 1.14 nGyh−1 with the calculated mean value of 84.770 ± 0.97 nGyh−1.