Perovskite solar cells (PSCs), have exhibited potential value for revolutionizing photovoltaic technology for space applications, and they have passed a series of tests in a simulated space environment. Nevertheless, the simulated space environment on land is definitely distinguished from the real-space conditions, and the results cannot completely represent the real operating state of PSCs in space. Herein, PSCs mounted on a high-altitude balloon are launched into near-space and the current–voltage characteristics are measured in situ throughout the 19-h flight, during which the PSCs are exposed directly to near-space and experience wide temperature variation, vacuum, and strong irradiation. Thus, the diurnal performance evolution of PSCs is obtained for the first time and a possible variation mechanism is identified. The PSCs present expected stability and a champion power density of ≈12 mW cm −2 at noon, which is demonstrated as the highest result achieved in near-space for PSCs. Additionally, despite a complex degradation process, the PSCs still deliver a high energy density comparable to that of silicon solar cells. Finally, the challenges facing the space application of PSCs are discussed. This work highlights the feasibility of PSCs in near space and provides direction for further exploration.
Sulfoselenide Sb 2 (S,Se) 3 , as a potential light-harvester, possesses a flexibly tunable bandgap of 1.1–1.7 eV to match solar radiation spectrum. However, the preparation of a homogenous Sb 2 (S,Se) 3 film is still challenging due to the different growth kinetics in sulfide and selenide compound, which consequentially leads to phase separation, lattice disorder and unfavored band level. This dilemma also occurs in the simple and well-established close space sublimation (CSS) method, and poses a devastating carrier recombination in Sb 2 (S,Se) 3 solar cells. Herein, alloyed powders of Sb 2 (S,Se) 3 are exquisitely synthesized by a thorough gas-solid reaction, delivering a uniform and single phase composition distribution as well as finely-tunable S/Se ratio. Compared with a physically mixed powder source (Sb 2 S 3 /Sb 2 Se 3 ), this alloyed Sb 2 (S,Se) 3 source allows for the fabrication of a homogeneous Sb 2 (S,Se) 3 thin film by CSS, rendering improved ( hk1 ) orientation, dense morphology, a more consistent longitudinal S/Se ratio, and enhanced energy level arrangement. These advancements contribute to enhance carrier transport and reduce carrier recombination. As a result, the efficiency of the solar cell is remarkably boosted from 2.59% to 5.46%, which is among of the highest PCE of full-inorganic Sb 2 (S,Se) 3 devices fabricated through the CSS method.