Energetic materials are functional materials capable of storing and rapidly releasing large amounts of chemical energy. Traditional energetic materials have evolved from physical mixtures of fuels and oxidizers to covalently bonded energetic molecules and, more recently, to multi-component systems in which different energetic components are integrated at the molecular or crystal level. However, conventional energetic materials often face an intrinsic trade-off among energy output, thermal stability, mechanical sensitivity and production cost.
Molecular perovskite energetic materials offer a different strategy. Based on the ordered ABX ₃ architecture , energetic organic cations, structural cations and oxidizing anions can be assembled into a periodic crystal framework. The replaceability of the A, B and X sites provides considerable freedom for regulating crystal packing, density, thermal stability, decomposition behavior and energetic performance.
A Modular Crystal Platform for Multicomponent Energetic Materials
A defining advantage of molecular PEMs is their modular structural design. The A-site can accommodate different organic cations, while the B-site and X-site can be replaced by different cations and energetic anions. The extended Goldschmidt tolerance factor provides a useful structural criterion for evaluating the compatibility of different components and screening possible perovskite structures. This modularity makes it possible to construct diverse energetic crystals through component substitution rather than relying solely on the design of individual energetic molecules.
Research has produced a broad family of perchlorate-, nitrate- and iodate-based PEMs, together with metal-free and metal-containing systems. Perchlorate-based DAP and PAP compounds generally exhibit high thermal stability and strong energetic performance, while nitrate-based systems such as DAN-2 provide lower mechanical sensitivity and sulfur-free combustion characteristics. Iodate-based PEMs, meanwhile, introduce high iodine content and broaden the potential functionality of molecular perovskites toward energetic biocidal applications.
The diversity of B-site components further expands this design space. Alkali-metal and silver-containing PEMs can provide high crystal densities and distinctive energetic and mechanical properties. In particular, silver-based molecular perovskites demonstrate promising combinations of energetic performance and sensitivity characteristics, illustrating how systematic site substitution can generate materials with differentiated functions.
Crystal Frameworks Govern Thermal Decomposition and Energy Release
Thermal stability is a critical parameter for the practical use of energetic materials. Studies of molecular PEMs reveal that their thermal decomposition cannot be understood simply from the strength of individual chemical bonds. Instead, the overall decomposition behavior is strongly influenced by the interaction between organic fuel cations and inorganic oxidizing frameworks.
In representative perchlorate-based PEMs such as DAP-4, thermal excitation can promote proton transfer between the organic and inorganic components, followed by the breakdown of the oxidizing cage and subsequent redox reactions. The unique confinement of the organic components within the perovskite framework therefore creates a synergistic decomposition pathway in which the fuel and oxidizer mutually promote chemical activation.
Comparative studies further demonstrate that changing the X-site anion can fundamentally alter thermal stability, decomposition kinetics and application characteristics. Perchlorate-based PEMs generally provide high thermal resistance and energy release, nitrate-based systems exhibit relatively milder decomposition and improved safety characteristics, while iodate-based materials introduce distinctive iodine-rich functionality. Thus, the X-site acts as an important structural and chemical lever for controlling the performance of molecular PEMs.
This review also highlights composite energetic perovskites as an important route toward overcoming the limitations of pure PEMs. Although some perchlorate-based PEMs possess high energy density and excellent thermal stability, their relatively high decomposition thresholds and ignition delays can restrict practical applications. Introducing catalytic or fuel components can modify decomposition kinetics, accelerate energy release and improve combustion characteristics.
From Composite Modification to Intelligent Molecular Design
A growing body of research has demonstrated that metal fuels, metal oxides and carbon-based nanomaterials can regulate the thermal decomposition and combustion behavior of PEMs. Metallic components can simultaneously serve as fuels and catalysts, while metal oxides and multicomponent catalytic materials can facilitate electron transfer and promote decomposition. Carbon-based materials such as graphene, carbon nanotubes, MXene and MoS₂ can provide additional catalytic and safety-related benefits. The nanoscale interfaces created by these components can enhance contact between different phases and improve the efficiency of energy transfer.
Beyond experimental modification, computational chemistry is becoming increasingly important for understanding and designing PEMs. Density functional theory can be used to examine crystal structures, electronic properties, intermolecular interactions, mechanical response and sensitivity-related descriptors. More recently, machine-learning methods combined with high-throughput DFT calculations have opened new possibilities for rapidly screening candidate structures and predicting key properties.
Emerging neural-network potentials can further extend simulations toward larger spatial and temporal scales, allowing researchers to investigate complex processes such as thermal decomposition and solid-state reactions with near-DFT accuracy. For PEMs, such approaches have helped clarify how B-site cations influence decomposition pathways and have revealed reaction mechanisms that are difficult to capture using conventional simulations.
The authors emphasize that machine learning remains at an early stage in energetic-perovskite research. Limited high-quality datasets, model interpretability and generalization to chemically complex energetic systems remain major challenges. Generative approaches such as MatterGen may nevertheless provide a future route toward exploring large chemical spaces and designing perovskite structures with targeted properties.
Toward Safer, More Diverse and Application-Oriented PEMs
The diversity of available A-, B- and X-site components remains limited, while the relationships between crystal structure, thermal stability, energy output and mechanical sensitivity are not yet fully understood. In particular, many PEMs exhibit relatively high friction sensitivity, and the microscopic mechanisms governing mechanical initiation require further investigation.
Future research will need to move beyond simply developing new compositions. A deeper understanding of structure–property–sensitivity relationships , combined with systematic structural modification, composite engineering, multiscale simulation and experimental validation, will be essential for achieving balanced energetic performance. Further, continued integration of molecular engineering, crystal chemistry, advanced computation and experimental verification could accelerate the transition of PEMs from laboratory-scale materials toward practical energetic systems.
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Contact author details:
Molecules and Materials Computation Institute, School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Xiaolingwei 200, 210094, PR China, E-mail addresses: xiao_jijun@njust.edu.cn(J.-j XIAO)
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Energetic Materials Frontiers
Research progress of molecular perovskite as a new platform for multicomponent energetic crystals
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.