Advances and Challenges in Tin Halide Perovskite Nanocrystals

Abstract

A major application limit for lead halide perovskite nanocrystals (NCs) is the presence of the highly toxic lead element, raising critical concerns of environmental pollution and health problems. To address this issue, tin halide perovskite NCs have been pushed to the forefront of perovskite research owing to their eco-friendly merit and tantalizing photophysical properties. In this Review, we critically summarize and assess the latest advances in the synthesis approaches of tin halide perovskite NCs including the hot injection, ligand-assisted reprecipitation, and chemical vapor deposition. More specifically, we detail the state-of-the-art preliminary studies in modulating their photophysical properties and in enhancing the stability with a variety of strategies such as precursor engineering, ligand engineering, and alloyed structure construction. Finally, we highlight the remaining challenges that need to be overcome to attain tin halide perovskite NCs with clear structure–property relationships and comparable physical and chemical properties to their lead-based cousins.

Engineering Surface Plasmons in Metal/Nonmetal Structures for Highly Desirable Plasmonic Photodetectors

“…On one hand, the electron-transition-based sub-bandgap optical absorption of Bdoped Si QDs extends the photodetection of QD/graphene hybrid phototransistors from the usual UV−vis region into the NIR region, while the LSPR of B-doped Si QDs further pushed the photodetection of QD/graphene hybrid phototransistors into the MIR region. As a consequence, this QD/graphene hybrid phototransistor achieved ultrabroadband photodetection range from UV to MIR with ultrahigh responsivity (∼10 9 A/W, Figure 5e), gain (∼10 12 , Figure 5f), and specific detectivity (∼10 13 Jones). Except considering a wide photodetection range and high responsivity, energy consumption in photodetector is also an important factor for practical application.…”

“…As one of the most important classes of optoelectronic devices, − photodetectors that can convert light into electric signals have attracted particular attention in the past decades, because of its wide application potentials in thermal imaging, optical guidance technology, and communication systems, etc. − Because of the excellent volumetric light absorption and carrier transport, photodetectors based on various low-dimensional semiconductors such as two-dimensional (2D) nanosheets, − one-dimensional (1D) semiconductor nanowires, − and zero-dimensional (0D) quantum dots (QDs) − have been heavily developed for achieving good device performance, including high photoresponsivity, fast response speed, and broad response range. Note that as one important component of the photoelectric sensor system, the photodetector’s size should be small enough to fulfill the constantly developing superintegrated circuits.…”

Tin-based halide perovskite materials: properties and applications

“… 85 So far, they have been utilized for high-efficiency solar cells, sensors, LEDs, and medical imaging devices. 86 However, their synthesis process is more complicated than lead-based NCs due to the unstable oxidation states of tin. The most common strategies to improve the stability of tin-based NCs include ligand functionalization, doping, alloying and core–shell structures.…”

Tuning the morphology and optoelectronic properties of AgBiI4 film through isopropanol treatment

“…Sn 2+ or Ge 2+ ) that has a similar valence electronic configuration. 1 Snbased perovskites have outstanding optoelectronic properties but pose the difficulty of chemical instability because Sn 2+ has a significant tendency to form stable oxygenated Sn 4+ . [2][3][4] The other strategy is to replace Pb 2+ with Bi 3+ or Sb 3+ because of the similar ionic radii and the same 6s 2 6p 0 electronic configuration.…”