The accelerating demand for clean energy, sustainable manufacturing, and environmentally resilient technologies has placed unprecedented emphasis on the thermal behaviour of inorganic, hybrid, and nanostructured materials. Calorimetry and advanced thermal analysis have become indispensable for uncovering the energetic, structural, and kinetic signatures that govern material stability, conversion efficiency, and long-term performance. As next-generation energy systems-from solid-state batteries and hydrogen storage media to catalytic platforms and high-temperature ceramics-grow increasingly complex, understanding heat transfer, phase evolution, interfacial processes, and thermal degradation is crucial for optimizing their real-world functionality. At the same time, environmental applications such as pollutant remediation, CO₂ capture, water treatment, and photocatalysis require materials capable of maintaining robust performance under wide thermal and chemical gradients. Recent advances in nano-engineered architectures, hybrid organic–inorganic frameworks, and multifunctional composites enable unprecedented control over thermal transport pathways and energy exchange mechanisms. Coupled with emerging high-resolution calorimetric tools, machine-learning-driven thermal modelling, and operando characterisation techniques, researchers can now map dynamic thermal events with remarkable precision.

Energy and environmental systems face demanding operational conditions where materials must withstand cyclic heating, reactive atmospheres, nanoscale confinement, and complex multiphase interactions. Correlating calorimetric data with real functional behaviour remains complicated because heat signatures often arise from overlapping chemical, structural, and transport phenomena. Nanostructures further complicates this interpretation by introducing size-dependent thermodynamics and unconventional phase transitions. Environmental materials such as sorbents, catalysts, and adsorbents also exhibit dynamic thermal responses influenced by moisture, pollutant loading, and surface reactions, requiring refined analytical methodologies. Yet the global shift toward renewable energy technologies and circular-material strategies has intensified the need for reliable thermal characterization to guide design decisions. Recent advancements, including micro- and nano-calorimetry, in situ thermal analysis under controlled atmospheres, and high-throughput calorimetric screening, are rapidly expanding the field’s capabilities. Integrating thermal analysis with spectroscopy, electron microscopy, computational simulations, and AI-assisted interpretation is enabling deeper insights into reaction energetics, stability windows, and degradation mechanisms of emerging materials. These developments are critical for optimizing energy storage efficiency, enhancing thermal management in electrochemical systems, improving catalyst lifetime, and designing environmentally compatible materials.

This Special Issue seeks innovative research that tackles emerging scientific and technological challenges while advancing calorimetry and thermal analysis to drive progress in energy conversion, environmental sustainability, and the development of next-generation thermally enabled materials and systems.

• AI-assisted thermal modelling for environmentally resilient and sustainable material design

• Reactive heat signatures and kinetic mapping of inorganic materials under extreme thermal cycling

• Calorimetric profiling of ion transport and redox energetics in solid-state and hybrid electrochemical systems

• Thermo-responsive behaviour of inorganic–organic interfaces in hybrid functional materials

• Heat-flow characterization of nanostructured adsorbents during pollutant capture and release

• Thermal transport modulation in nano-architecture materials for energy harvesting

• Exothermic and endothermic pathways in photocatalytic or electrocatalytic reaction systems

• Calorimetric evaluation of thermal runaway suppression strategies in next-generation batteries

• Thermodynamic assessment of phase stability in multi-component oxide or chalcogenide systems

• Energetics of structural reconfiguration in porous frameworks under gas or vapor uptake

• Coupled thermal–chemical processes in materials for CO₂ conversion and environmental remediation

• Operando calorimetry for monitoring real-time transformations in catalytic or energy devices

• Thermo-oxidative resistance studies on high-temperature environmental barrier materials

• Machine learning-driven prediction of phase transitions in energy materials

This special issue of the Journal of Thermal Analysis and Calorimetry commemorates the 60th anniversary of the Thermal Methods Group (TMG) of the Royal Society of Chemistry. A landmark year that celebrates both the enduring legacy and the future-facing developments of thermal analysis and calorimetry. The TAC2025 conference, on which the contributors to this special issue have been drawn, brought together a distinguished and diverse cohort of thermal analysts, material scientists, engineers and calorimetrists. The conference included world-renowned experts, industrial practitioners, and early career academics. Presentations spanned an extraordinary breadth of topics, from the thermal stability of propellants in defence applications, to food science, pharmaceutical chemistry, and even the advanced materials used in Formula One engineering. This milestone event also marked the conclusion of Dr Milan Antonijevic’s term as Chair of the TMG, whose leadership and inclusive approach have helped grow and sustain the group during the challenging post-COVID era. Together with Dr Vicky Kett and Dr Gareth Parkes, all leaders in the field, respected academics and former TMG Chairs, they serve as editors for this celebratory issue, which reflects the vibrancy, depth, and interdisciplinary nature of thermal analysis and calorimetry as it enters a new era of scientific exploration and innovation.