With the development of internet of things and artificial intelligence electronics, metal oxide semiconductor (MOS)‐based sensing materials have attracted increasing attention from both fundamental research and practical applications. MOS materials possess intrinsic physicochemical properties, tunable compositions, and electronic structure, and are particularly suitable for integration and miniaturization in developing chemiresistive gas sensors. During sensing processes, the dynamic gas–solid interface interactions play crucial roles in improving sensors’ performance, and most studies emphasize the gas–MOS chemical reactions. Herein, from a new view angle focusing more on physical gas–solid interactions during gas sensing, basic theory overview and latest progress for the dynamic process of gas molecules including adsorption, desorption, and diffusion, are systematically summarized and elucidated. The unique electronic sensing mechanisms are also discussed from various aspects including molecular interaction models, gas diffusion mechanism, and interfacial reaction behaviors, where structure–activity relationship and diffusion behavior are overviewed in detail. Especially, the surface adsorption–desorption dynamics are discussed and evaluated, and their potential effects on sensing performance are elucidated from the gas–solid interfacial regulation perspective. Finally, the prospect for further research directions in improving gas dynamic processes in MOS gas sensors is discussed, aiming to supplement the approaches for the development of high‐performance MOS gas sensors.

Ultra-fine CdS quantum dots modified TiO₂ nanotube arrays (TiO₂-NTs) with enhanced visible-light activity are fabricated via a cathodic electro-deposition combined with ion-exchange route (CEDIE). The as-formed CdS quantum dots were highly dispersed both outside and inside the TiO₂-NTs. The proposed CEDIE strategy results in the strong combination and heterojunctions between CdS and TiO₂ through Cd–O bonds. The crystal phases, chemical compositions and physicochemical properties of as-obtained CdS/TiO₂-NTs have been investigated based on various characterizations. Compared to CdS/TiO₂-NTs prepared via a sequential chemical bath deposition method, the as-synthesized samples exhibit stronger visible-light absorption capability, higher photocurrent density, excellent stability, and greatly enhanced photoelectrocatalytic (PEC) activity toward degradation of methyl orange (MO) aqueous solutions under visible light irradiation (λ > 400 nm). Such enhanced PEC activity may be ascribed to the strong combination and heterojunctions between CdS and TiO₂, favorable for visible-light response and charge separation of TiO₂-NTs.

Black Ti³⁺/TiO₂ single-crystals synthesized via an ionothermal process exhibited high activity for the photocatalytic degradation of pollutants and hydrogen evolution reaction.