On the role of thermo-electro-ionic dynamics in hysteresis and transient performance of perovskite solar cells

Abstract

Understanding the thermal origins of performance instabilities and hysteresis in perovskite solar cells (PSCs) is essential for advancing their long-term stability and reliable operation. In this perspective, we develop a novel coupled multiphysics mathematical framework that integrates layer-resolved optical absorption, non-isothermal electronic–ionic transport, and a layer-resolved, self-consistent energy balance with explicit bulk and interfacial heat-generation pathways. These pathways include hot-carrier thermalization, Joule heating, Peltier effects, radiative/non-radiative recombination, and parasitic optical absorption. This mathematical framework extends PSC characterization beyond conventional J–V analysis by introducing temperature–voltage (T–V) and heat–voltage (P–V) characteristics curves, enabling quantitative tracking of transient self-heating and its interactions with electronic–ionic dynamics. It is shown that PSCs develop internal thermal inertia that evolves on timescales comparable to ionic relaxation under bias sweeps, leading to strongly scan-rate-dependent heating. At intermediate scan rates, this thermo-electro-ionic coupling produces non-monotonic temperature evolution with dual-peak profiles during forward sweeps and pronounced T–V hysteresis, coinciding with S-shaped J–V distortions that are shifted to lower scan rates relative to isothermal predictions. The scan-rate-dependent heating can be resolved into interfacial- and bulk-dominated regimes: interfacial heating governs the temperature evolution at low-to-intermediate scan rates, bulk heating controls the profile at intermediate-to-high rates, while rapid sweeps leave insufficient time for heat to accumulate, ultimately driving the response toward an ion-frozen, quasi-isothermal limit. These distinct thermal regimes reshape carrier extraction asymmetry, internal field screening, and mobile-ion redistribution, thereby aggravating or mitigating hysteresis relative to isothermal electronic–ionic transport predictions. Neglecting thermo-electro-ionic effects underestimates transient temperature rises by >10 K and misidentify the scan-rate window associated with S-shaped J–V distortions. By integrating these multiphysics effects, the framework provides a diagnostic tool for next-generation PSC characterization and identifies design strategies such as interface engineering, nanostructural thermal management, and scan-protocol optimization to enhance device performance and stability under real-world operating conditions.