Strain engineering, as a cutting-edge method for modulating the electronic structure of catalysts, plays a crucial role in regulating the interaction between the catalytic surface and the adsorbed molecules. The electrocatalytic performance is influenced by the electronic structure, which can be achieved by introducing the external forces or stresses to adjust interatomic spacing between surface atoms. The challenges in strain engineering research lie in accurately understanding the mechanical impact of strain on performance. This paper first introduces the basic strategy for generating the strain, summarizes the different strain generation forms and their advantages and disadvantages. The progress in researching the characterization means for the lattice strains and their applications in the field of electrocatalysis is also emphasized. Finally, the challenges of strain engineering are introduced, and an outlook on the future research directions is provided.

The high sensitivity of room-temperature gas sensors is the key to innovation in the areas of environment, energy conservation and safety. However, metal-oxide-based sensors generally operate at high temperatures. Herein, we designed three ZrO₂-based sensors and explored their NO₂ sensing properties at room temperature. ZrO₂ with three different morphologies and microstructure were synthesized by simple hydrothermal methods. The microstructures of sensing materials are expected to significantly affect gas sensing properties. The rod-shaped ZrO₂ (ZrO₂-R) displayed the advantages such as higher crystallinity, larger pore size, narrower band gap and more chemisorbed adsorbed oxygen, compared to hollow sphere-shaped ZrO₂ (ZrO₂-HS), stellate-shaped ZrO₂ (ZrO₂–S). The ZrO₂-R sensor showed the highest response towards 30 ​ppm NO₂ (423.8%) at room temperature, and a quite high sensitivity of 198.0% for detecting 5 ​ppm NO₂. Although ZrO₂-HS and ZrO₂–S sensors exhibited lower response towards 30 ​ppm NO₂ (232.9% and 245.1%), the response time and recovery time of these two sensors are 5 ​s/19 ​s and 4 ​s/3 ​s, respectively. This work can provide a new strategy for the development of room-temperature metal-oxide-based sensors.