Abstract: The present disclosure relates to a negative ion generating device and an air purifier. The negative ion generating device includes a housing, a negative ion assembly, and a cleaning assembly. The negative ion assembly is arranged to the housing, and the negative ion assembly includes a conductive fiber brush. The cleaning assembly is arranged to the housing, the cleaning assembly includes a driving mechanism and a cleaning member, and the cleaning member can move under action of the power provided by the driving mechanism, and contact or separate from the conductive fiber brush during movement.

Abstract: An inlet collector for a centrifugal fan and a centrifugal fan are provided. By arranging a tragus-shaped section in a guiding section, reverse flow caused by intersection of inlet leakage flow at a volute tongue side and inlet airflow is blocked by the tragus-shaped structure in movement process, and the leakage flow no longer collide with the inlet airflow. An inner curved surface of the tragus-shaped section controls backflow to change smoothly along an inner wall surface of the tragus-shaped section and re-enter a volute for circulation. A tragus profile is adopted to guide the airflow to change more smoothly in the velocity direction near the wall of the guiding section, so as to effectively reduce the impact of the inlet airflow on the guiding section. By using the inlet collector, energy loss of airflow is reduced, vortex formation is suppressed, and aerodynamic performance and fan noise are improved.

Abstract: A photovoltaic cell (10) is disclosed that includes an active layer (20) sandwiched by top and bottom graphene-ferroelectric electrodes (30T, 30B) each having a graphene layer (32) and a polarized ferroelectric layer (34). The polarized ferroelectric layer defines an internal electric field (EI). Light (50) irradiates the active layer through the top graphene-ferroelectric electrode, causing the generation in the active layer of electrons (e) and holes (h) as charge carriers. The internal electric field causes the electrons and holes to move towards opposite electrodes, giving rise to a photocurrent (ipc), while also mitigating undesirable charge-carrier recombination.