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This review aims to consolidate scattered literature on thermally sprayed coatings with nonionizing electromagnetic (EM) wave absorption and shielding over specific wavelengths potentially useful in diverse applications (e.g., microwave to millimeter wave, solar selective, photocatalytic, interference shielding, thermal barrier-heat/emissivity). Materials EM properties such as electric permittivity, magnetic permeability, electrical conductivity, and dielectric loss are critical due to which a material can respond to absorbed, reflected, transmitted, or may excite surface electromagnetic waves at frequencies typical of electromagnetic radiations. Thermal spraying is a standard industrial practice used for depositing coatings where the sprayed layer is formed by successive impact of fully or partially molten droplets/particles of a material exposed to high or moderate temperatures and velocities. However, as an emerging novel application of an existing thermal spray techniques, some special considerations are warranted for targeted development involving relevant characterization. Key potential research areas of development relating to material selection and coating fabrication strategies and their impact on existing practices in the field are identified. The study shows a research gap in the feedstock materials design and doping, and their complex selection covered by thermally sprayed coatings that can be critical to advancing applications exploiting their electromagnetic properties., This work was supported by the Pump Priming funding at Robert Gordon University, Aberdeen (project ID: 232073: Thermally sprayed metamaterial coatings for photovoltaic energy harvesting applications (#themetacoat)), in collaboration with University of Nottingham, Cranfield University, London South Bank University, and University of Exeter. S.G. and N.K. are thankful for the funding support received from the UKRI (grant (s) nos. EP/L016567/1, EP/S013652/1, EP/S036180/1, EP/T001100/1, and EP/T024607/1), Transforming the Foundation Industries NetworkPlus Feasibility study award to L.S.B.U. (EP/V026402/1), the Royal Academy of Engineering via grants IAPP18-19\295 and TSP1332, The Hubert Curien Partnership award 2022 from the British Council, and the Newton Fellowship award from the Royal Society (NIF\R1\191571). This work made use of Isambard Bristol, UK supercomputing service, accessed by Resource Allocation Panel (RAP) grant, as well as ARCHER2 resources (Project e648). W.W. is also thankful to the research support provided by the UKRI grant no. EP/S030301/1 (ANISAT).

For the past twenty years, there has been increasing interest and investment in solar photovoltaic (PV) technology. One particular area of interest is the development of concentrating PV (CPV), especially for use in building integration. Many CPV designs have been developed and investigated. This paper aims at producing a mathematical modelling using MATLAB programme to predict the current-voltage (I-V) and power-voltage (P-V) characteristics of a static CPV. The MATLAB programme could also simulate the angular response of the CPV designs-which has never been explored in the previous literature. In this paper, a CPV known as the rotationally asymmetrical dielectric totally internally reflecting concentrator (RADTIRC) was analysed. A specific RADTIRC design that has an acceptance angle of ±40° was investigated in this paper. A mathematical modelling was used to simulate the angular characteristics of the RADTIRC from −50° to 50° with an increment 5°. For any CPV, we propose that the value of opto-electronic gain, Copto-e needs to be included in the mathematical model, which were obtained from experiments. The range of incident angle (±50°) was selected to demonstrate that the RADTIRC is capable of capturing the sun rays within its acceptance angle of ±40°. In each simulation, the I-V and P-V characteristics were produced, and the short circuit current (Isc), the open-circuit voltage (Voc), the maximum power (Pmax), the fill factor (FF) and the opto-electronic gain (Copto-e) were determined and recorded. The results from the simulations were validated via experiments. It was found that the simulation model is able to predict the I-V and P-V characteristics of the RADTIRC as well as its angular response, with the highest error recorded for the Isc, Voc, Pmax, FF and Copto-e was 2.1229%, 5.3913%, 9.9681%, 4.4231% and 0.0000% respectively when compared with the experiment.