A vertical greening system is becoming increasingly crucial in resolving the energy crisis and environmental problems in a sustainable ecosystem. Researchers have conducted a comprehensive study on vertical greening systems from technology, functional and architectural perspectives. These include ecological, economic and social functions. Most of the current studies emphasize the benefits of vertical greening systems to the environment, while vertical greening technology and its socio-economic benefits receive insufficient attention. In order to study the vertical greening field in depth, this paper comprehensively and systematically summarizes vertical greening technology and functions. Meanwhile, based on the Web of Science (WOS), CiteSpace was used to analyze the relevant literature in the vertical greening field from 2012 to 2022, to explore the hot spots, development status and future trends of vertical greening technology, and to build a knowledge map in the vertical greening field. The research shows that as a low impact development technology, the vertical greening system has received the most extensive attention in the past few years. Air quality, microclimate regulation and energy have always been the focus and hot issues of people’s attention. The future research directions are cooling effect, active system and indoor space. This study is aimed at promoting the future development of vertical greening system technology and providing reference and direction for researchers, planners and developers, as well as individuals interested in future urban and rural planning.

In recent years, repeated outbreaks of airborne viruses have normalized human coexistence with these viruses. The complex turbulence and vortices generated by different fan types and operation modes affect virus removal effectiveness. This paper reviews the potential impact and actual effectiveness of different fans in mitigating indoor virus transmission, highlighting their advantages and limitations. Downward rotating ceiling fans can rapidly dilute virus concentration (21–87%) in the breathing zone due to jet cores, with efficiency depending on rotational speed and particle diameter. However, the reprocessing problems of large particles being deposited on surfaces, and small particles settling and rebounding into the air remain unresolved. Upward-rotating ceiling fans do not contribute to indoor virus removal. Exhaust fans generate a negative-pressure environment, which helps expel viruses quickly. But improper vortex zones can increase virus retention time 16–40 times. Air-apply fans effectively dilute and transport viruses only when delivering airflow exceeding 0.5 m/s directly into the breathing zone. Additionally, combined fan strategies remain underexplored, despite potential benefits. This review underscores the need for standardized definitions of particle removal effectiveness and calls for further research on how climatic conditions and thermal comfort influence fan-based interventions.