There is no secret sauce needed. The Plantower sensors tell you the PM2.5 in micrograms directly and we just display it to the OLED display or send it to a server. It is all open source so you can check the code.
Re:The health benefits of better air
by simondotau on Wednesday April 28, 2021 @06:43AM
(#26967861)
Thanks.
I am interested in replicating your hardware stack but implementing the software stack using the esphome framework which supports all of the components used in your DIY solution.
https://esphome.io/components/sensor/senseair.html
https://esphome.io/components/sensor/pmsx003.html
https://esphome.io/components/sensor/sht3xd.html
https://esphome.io/components/display/ssd1306.html