Other home sensors

I’m looking for other ideas for sensors that I could use my my smart home. I’m wondering about things like…

  • particulate matter
  • CO/CO2
  • VOCs
  • smoke

I’m debating whether to go Zigbee or WiFi and battery or mains. There aren’t huge numbers of these kinds of devices that can be connected to Home Assistant so limiting to a particular connection method or power source might make it even more difficult to find some sensors.

Has anyone added these kind of sensors and if so what route did you follow?