Probing Perovskite Carrier Dynamics under Sunlight

Understanding the nature of photogenerated carriers and their subsequent dynamics in perovskites is important for the development of related materials and devices. Most ultrafast dynamic measurements on the perovskite materials were conducted under high carrier densities, which likely obscures the genuine dynamics at low carrier densities under solar illumination conditions. In this study, we presented a detailed experimental study of the carrier density-dependent dynamics in hybrid lead iodide perovskites using a highly sensitive transient absorption spectrometer. We found that the carrier lifetime was about a hundred nanosecond in the linear response range, representing sunlight excitation, which was much longer than under high carrier densities. We also elucidated that the fast carrier decay (<1 ps) and the medium decay processes (tens of ps) occurred via the defect state trapping, and we determined its effects on the utilization percentage of photogenerated carriers through quantitative analysis. Furthermore, we obtained the Shockley-Queisser limit that took into account the carrier trapping effect, which directly reflected the material performance.

Ab-initio study on the two-dimensional anisotropic monolayers ScXY (X =S, Se; Y = Cl, Br) for the photocatalytic water splitting applications with high carrier mobilities

Metal oxyhalides have been broadly studied recently due to their hierarchical structures and promising functionalities. Herein, a thorough study of newly modeled monolayers ScXY (X = S, Se; Y =...

β-SnS/GaSe heterostructure: a promising solar-driven photocatalyst with low carrier recombination for overall water splitting

Various two-dimensional (2D) materials have been well investigated as promising high-efficiency photocatalysts for solar-driven water splitting, while the high carrier recombination greatly hinders their practical application. One effective route to...

Scalable printing of two-dimensional single crystals of organic semiconductors towards high-end device applications

The past several decades have witnessed a vast array of developments in printable organic semiconductors, where successes both in synthetic chemistry and in printing technology constituted a key step forward to realization of printed electronics. In this review, we highlight specifically on materials science, charge transport, and device engineering of —two-dimensional single crystals—. Defect-free organic single-crystalline wafers manufactured via a one-shot printing process allows remarkably reliable implementations of organic thin-film transistors with decently high carrier mobility up to 10 cm2 V-1 s-1, which has revolutionized the current printing electronics to be able to meet looming IoT challenges. This review focuses on the perspective of printing two-dimensional single crystals with reasonable areal coverage, showing their promising applications for practical devices and future human society, particularly based on our recent contributions.