Chiral organic-inorganic hybrid halides show significant potential for applications in circularly polarized photodetection, chiral-induced spin selectivity effects (CISS), and nonlinear optics. However, the widespread use of toxic lead element poses environmental concerns, hindering the further applications. Herein, we synthesized a zero-dimensional (0D) lead-free chiral antimony-based halide (R/S-MBA)₄Sb₂Br₁₀ with the coexistence of polarity and crystallographic chirality. The halides exhibit unique magneto-chiroptical effects due to the field-effect-induced fine-tuning of exciton energy, which is the first observation in chiral antimony-based halides. Furthermore, owing to its significant spontaneous polarization (5.0 μC/cm²) and optical chirality (g_CD = 0.0018), (R/S-MBA)₄Sb₂Br₁₀ halide exhibits excellent performance in self-powered circularly polarized photodetection, nonlinear optics, and CISS effects. The self-powered photodetector demonstrates high sensitivity with distinguishable factors (g_res = 0.53/-0.51 @ 0V) and broad spectral response. The single crystal (R/S-MBA)₄Sb₂Br₁₀ also exhibits a high second-harmonic polarization response asymmetry factor (g_SHG-CD = 0.98/-0.70) and strong second-harmonic generation intensity. These performances are among the best reported for chiral halides. Our research not only sheds new light on the investigation of magneto-chiroptical phenomena, but also marks a significant advancement in realizing high-sensitivity circularly polarized light detection within the realm of lead-free polar materials.

Zero-dimensional metal halides are of unique structures and tunable photoluminescence properties, showing great potential applications such as light-emitting diodes (LEDs) and sensing. Herein, we successfully synthesized Cu⁺ doped (MA)₂ZnCl₄ metal halides by a slow evaporation solvent method. The introduction of Cu⁺ results in sky-blue self-trapped exciton emission in (MA)₂ZnCl₄ at 486 nm at room temperature, and a photoluminescence quantum yield is as high as 54.9%. Interestingly, at low temperatures, Cu⁺-doped (MA)₂ZnCl₄ exhibits two emission peaks located at 482 and 605 nm, respectively. This temperature-dependent dual emission indicates two excited state structures that exist on the triplet excited-state potential energy surface. In addition, the temperature sensor we fitted has good performance (S_r = 1.65 %·K⁻¹), which is the first attempt in Cu⁺ doped Zn-based metal halides. Our work enriches the family of sky-blue metal halides and provides a promising strategy for building sky-blue LEDs.