Physical design and evaluation of a high-intensity accelerator-based D-D/D-T fusion neutron source

Inorganic CsPbI2Br Perovskite Solar Cells: The Progress and Perspective

“…Photo-induced phase segregation is observed as a common phenomenon in MA-based hybrid perovskites, even in materials with single halide components like MAPbI 3 and MAPbBr 3 . [31] This segregation becomes more serious in the mixed-halide perovskites (MAPb(Br x I 1Àx ) 3 ), resulting in formation of I-and Br-rich domains. [32] The photo-induced halide segregation seriously damages the device performance, leads to open-circuit voltage (V oc ) decrease and photo-induced traps.…”

“…[33] Since the halide segregation is as the result of ion migration, therefore, it can be suppressed by increasing the ion migration barrier. The light stability of cesium-based lead mixed-halide inorganic perovskites was first investigated by McGehee et al [34] A series of CsPb(Br x I 1Àx ) 3 films with different compositions have been illuminated under a fluence of 100 mW cm À2 . The photoluminescence (PL) peak position has been recorded over time.…”

“…The lead halide perovskite materials have been under the spotlight owing to the excellent optical and electrical properties, such as high absorption coefficient, [1] low exciton binding energy, [2] ultralong charge carrier diffusion length, [3] and superhigh defect tolerance with low trap state density. [4] The power conversion efficiency (PCE) of perovskite solar cells (PSCs) now stands at 23.3%, [5] starting from 3.8% as reported by Miyasaka et al in 2009.…”

“…[9] Suffering from the poor phase stability, the allinorganic PSCs developed late, but progressed fast in the last 2 years. Until 2015, the genuine inorganic CsPbI 3 PSCs with a PCE of 2.9% was demonstrated first by Snaith et al through reducing grain size with the aid of hydriodic acid (HI). [10] The next year, Luther et al published a significant paper in Science.…”

“…Since then, various methods including ion doping, [12] small molecular or polymer modification, [13] and dimension control [14] have been developed rapidly to stabilize the cubic phase of CsPbI 3 via reducing grain size. The passivation of grain boundaries or surface states becomes critical for high-efficiency CsPbI 3 PSCs, because of the fact that there will be more grain boundaries and thus more surface states as the crystal size decreases. [15] In 2016, Snaith et al demonstrated that the cesium lead mixed-halide perovskites, CsPbI 2 Br, are stable in the cubic phase at room temperature even for bulk materials.…”