Methods and systems are provided for sensing particulate matter by a particulate matter sensor positioned downstream of a diesel particulate filter in an exhaust system. In one example, a method may include accumulating incoming particulate matter by applying a higher bias to a first trap of the particulate matter sensor, and further charging the particulate matter and forming highly charged dendrites. The method further includes capturing the dendrites exiting the first trap by applying a lower bias to a second trap also housed within the same particulate matter sensor, thereby reducing the effects of exhaust flow rate on the particulate matter sensor and further increasing the sensitivity of the particulate matter sensor.