Recent Research on the Applications of Amorphous Materials

Inorganic amorphous materials continue to play a foundational role in modern materials science, enabling advances in photonics, catalysis, electronics, energy storage, and biomedical technologies. Their unique properties arise from the absence of long-range order, the presence of flexible bonding environments, and the ability to tailor defect populations, which together enable mechanical resilience, optical tunability, chemical stability, and multifunctionality. Recent progress in their synthesis and in situ characterization has deepened our understanding of amorphous structures and property relationships, as well as facilitating breakthroughs in metallic glasses, oxide glasses, amorphous semiconductors, and functional thin films [1,2,3].

This Special Issue of Inorganics highlights representative advances across amorphous and inorganic material systems, illustrating how compositional tuning, structural engineering, and defect modulation synergistically enable performance improvements in electronics, energy devices, dental materials, and radiation-resistant systems.

Metallic glasses (MGs) remain a central topic in amorphous materials research due to their high strength, extended elastic limit, and corrosion resistance. Over the past decade, deep insights have been gained into their glass transition behavior, deformation mechanisms, and structural relaxation dynamics [1,2]. Feng et al. provide a comprehensive review of amorphous alloy development, covering formation mechanisms, atomic packing, and emerging applications from aerospace components to catalysis [4]. Their assessment resonates with broader theoretical frameworks on metallic glass processing and glass-forming ability [3,5].

Amigo et al. investigate the dynamic plasticity of CuZr MG/Cu composites under high-velocity impact, showing that crystalline inclusions facilitate shear-band multiplication and energy dissipation [6]. These findings complement atomistic analyses of mechanical instability and shear-transformation-zone (STZ) activation in amorphous alloys [7]. Additionally, Jiang et al. demonstrate that minor Ag additions greatly enhance the corrosion resistance and antibacterial properties of Fe-based bulk metallic glasses (BMGs) while maintaining structural integrity and biocompatibility [8], consistent with studies on micro-patterning and surface modification of BMGs for biomedical applications [9].

Functional inorganic glasses remain indispensable in photonics, ionics, and optoelectronics. Vijayalakshmi et al. reveal strong NIR emission and tunable dielectric behavior in Ni²⁺-activated PbO–GeO₂ glasses, demonstrating their potential for solid electrolytes and nonlinear photonic components [10]. These findings align with recent efforts to develop multi-component glass systems with controlled phase separation, enhanced stability, and tailored optical transitions [3,11,12,13,14].

Deng et al. highlight an amorphous phase separation (APS) engineering strategy that suppresses crystallization in SiO₂–Al₂O₃–P₂O₅–Li₂O–ZrO₂ glass systems [15]. Their approach echoes broader interest in leveraging nanoscale heterogeneity to enhance glass stability and mechanical strength [12,13].

In amorphous semiconductor systems, Ramos-Serrano et al. analyze SiO_xC_y:H films produced via HW-CVD, demonstrating how oxygen-deficient centers and band-tail states govern photoluminescence behavior [16]. These results complement major developments in amorphous oxide semiconductors (AOS), such as IGZO and related high-mobility amorphous oxides used in next-generation thin-film transistors [17,18], as well as chalcogenide-based amorphous photonic materials for broadband optical modulation [19].

Velandia et al. report high-responsivity microbolometers based on nitrogen-doped amorphous SiGe:H,N frameworks [20], contributing to the growing interest in amorphous semiconductors for low-cost IR sensing and flexible electronics [21].

Understanding amorphization under extreme environments is vital for nuclear materials, space technology, and semiconductor reliability. Xiao et al. demonstrate that helium implantation induces nanocrystalline-to-amorphous transitions in ZrN thin films, with He atoms segregating along grain boundaries to initiate structural collapse [22]. Their atomic-level insights complement theoretical analyses of irradiation-induced amorphization, defect accumulation, and bubble evolution in ceramic and metallic systems [23,24,25].

These studies underscore the broader importance of interface-dominated amorphization, grain-boundary instability, and defect-driven phase transitions in nanoscale materials, as highlighted in recent reviews on radiation effects in oxides and carbides [23,24].

Dental and biomedical inorganic materials represent another area of rapid progress. Chen et al. review calcium-based remineralization systems (e.g., hydroxyapatite, α/β-TCP, and CPP-ACP), highlighting their antibacterial action and regenerative potential [26]. Their formulations align with recent developments in bioactive glass systems that promote ion release, pH regulation, and enamel regeneration [19,27].

De et al. report fluoride-modified nanotube-reinforced glass ionomer liners with improved antibacterial properties against S. mutans [28]. These findings echo parallel advances in inorganic antimicrobial coatings and hybrid calcium-phosphate materials for dental preservation [29,30].

Further, the work on Ag-modified Fe-based BMGs by Jiang et al. [8] complements the broader research trend of designing amorphous metallic biomaterials with controlled ion release, enhanced corrosion resistance, and multifunctional antibacterial behavior [30,31].

Amorphous materials have emerged as promising candidates for electrochemical energy storage and catalysis due to their abundant active sites and flexible coordination environments. Amorphous oxides and hydroxides have shown excellent performance in supercapacitors, electrocatalytic water splitting, and lithium storage [31,32,33]. These works provide a complementary backdrop to the functional amorphous materials featured in this Special Issue, expanding the design space for sustainable energy devices.

Together, the contributions in this Special Issue reflect the breadth, depth, and growing sophistication of amorphous materials research. From metallic glasses and radiation-resistant ceramics to photonic glasses and dental materials, the field is being reshaped by multi-scale modeling, high-throughput synthesis, machine-learning-assisted design, and advanced in situ characterization [34]. Future progress will depend on understanding atomic-scale features—short-range order, bonding configurations, defect motifs, and integrating them with macroscopic performance requirements to develop robust, sustainable, high-performance amorphous systems across structural, photonic, biomedical, and energy applications.

As Guest Editors, we sincerely thank all authors and reviewers whose work made this Special Issue possible. We also extend our appreciation to the editorial team of Inorganics for their continued support in promoting advances in inorganic and amorphous materials science.