Recently, metal nanoclusters (MNCs) emerged as a new class of luminescent materials and have attracted tremendous interest in the area of luminescence-related applications due to their excellent luminous properties (good photostability, large Stokes shift) and inherent good biocompatibility. However, the origin of photoluminescence (PL) of MNCs is still not fully understood, which has limited their practical application. In this mini-review, focusing on the origin of the photoemission emission of MNCs, we simply review the evolution of luminescent mechanism models of MNCs, from the pure metal-centered quantum confinement mechanics to ligand-centered p band intermediate state (PBIS) model via a transitional ligand-to-metal charge transfer (LMCT or LMMCT) mechanism as a compromise model.

The elucidation of structure and formation mechanism of dendritic mesoporous silica nanospheres is in extensive debates. This review summarizes the recent advance on their synthesis and application, and more concerned on their kinetic formation mechanics.

The well-known Stöber method has been widely used to synthesize nonporous silica nanospheres (NPs), however, in the absence of surfactant templates, the synthesis of mesoporous silica nanospheres (MSNs) has not been achieved. Herein, in the absence of organic surfactant templates, by a simple premixing of three components tetraethoxysilane–water–ethanol (TEOS–H₂O–EtOH) with a precise molar ratio, the parent silica nanoparticles with a low condensation degree and controlled particle size can be readily obtained. Subsequently, via a simple two-step post-treatment, the obtained MSNs exhibited a high surface area (ca. 500 m² g⁻¹), accessible mesopores (3.0 nm), and a large pore volume (0.87 mL g⁻¹), similar to those of MCM-41 and SBA-15 silicas. The unique self-templating role of the ‘pre-Ouzo’ effect of ternary surfactant-free TEOS–H₂O–EtOH systems was proposed to understand the formation of mesoporosity.