The discovery of rare‐earth free luminescent materials with blue‐light‐excitable characteristic is of great importance for solid‐sate lighting applications. Herein, a Cu(I)‐based 0D luminescent hybrid (1,3‐dppH2)2Cu4I8∙H2O is synthesized by a facile solution method, and it shows the orange‐red emission peaking at 625 nm upon 460 nm excitation. The structure‐related luminescence mechanism has been elaborated by experimental and theoretical investigations. Moreover, the emission intensity remains unchanged even after continuous water treatment for 60 days due to the improved structural stability originating from intermolecular π–π interaction between organic cations. A warm white light‐emitting diode (LED) device with the color rendering index of 91.4% has been fabricated by combining the 440 nm LED chip, green‐emitting Lu3Al5O12:Ce3+, and (1,3‐dppH2)2Cu4I8∙H2O. This work provides a new design route towards 0D cuprous halide materials and will initiate more exploration of their intrinsic luminescence mechanism.

In2O3 is of particular interest as a wide-gap transparent semiconductor oxide, in which the shallow donor defect of the oxygen vacancy plays an important role in electronic properties. Herein, we focus on the oxygen vacancy with various concentrations in In2O3, where the distribution is found to be crucial to the structural stabilities. For a specific supercell, the formation energies of oxygen-vacancy pairs remarkably depend on the distance between the two vacancies, which can be used to determine the oxygen-vacancy distribution in the nonstoichiometric In2O3 structure. Interestingly, when two oxygen vacancies share a same In atom, the structures are approximately stabilized with the decreasing of distance. However, when two oxygen vacancies are not attached to the same In atom, the structures become more stable with the increasing of distance between vacancies. In addition, the gap states induced by oxygen vacancies move toward the valence band maximum (VBM) when the nearest distance between the two vacancies decreases, which will have a great effect on the conductivity.

Luminescent organometallic halide crystals, especially with single-component white emission, are urgently needed for light-emitting diode (LED) applications. Barriers for the applications, however, lie in their lead toxicity, poor stability, and low photoluminescence quantum yield (PLQY). Here, a one-dimensional Cu­(I)-based hybrid metal halide (C12H24O6)­CsCu2Br3 is designed and prepared via a simple solution method. Upon 365 nm excitation, a broad-band white light emission centered at 535 nm with a full width at half maximum of 186 nm and a PLQY of 78.3% is monitored. The experimental results together with calculation data indicate that the existence of the split peaks at 486 and 570 nm at a low temperature is attributed to the decrease of energy level degeneracy by virtue of the lattice distortion. Moreover, the stability along with the good device performance of the as-fabricated white LED was also discussed. The results demonstrate that (C12H24O6)­CsCu2Br3 is highly competitive in lighting application, and it can further enable breakthrough material design for new luminescent organometallic halides.

Oxygen vacancy is crucial to the optical properties in In[Formula: see text]O[Formula: see text], however, the single oxygen vacancy model fails to explain the observed multi-peak emission in the experiment. Herein, we have theoretically investigated the diversity of oxygen vacancy distribution, revealing the relationship between the defect configurations and the optical properties. Combining the first-principles calculations and bayesian regularized artificial neural networks, we demonstrate that the structural stability can be remarkably enhanced by multi-oxygen vacancy aggregation, which will evolve with the defect concentration and temperature. Notably, our results indicate that the single oxygen vacancy will induce the emission peaks centered at 1.35 eV, while multi-peak emission near 2.35 eV will be attributed to the distribution of aggregated double oxygen vacancies. Our findings provide a comprehensive understanding of multi-peak emission observed in In[Formula: see text]O[Formula: see text], and the rules of the vacancy distribution may be extended for other metal oxides to modulate the optical properties in practice.

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