We report fabrication and successful testing of a gas ionization sensor made of silver nanowires (AgNWs) sandwiched between two parallel plates. The device was tested in low pressure argon gas (0.1≤ P ≤0-4 torr) where the breakdown voltages (Vb) were recorded against pressure. The new device displayed considerably lower Vb compared to its gold nanowire (AuNW)-based counterparts. The reduction of Vb was justified based on the increase in the secondary electron emission factor on AgNWs due to the lower workfunction of silver. We have also developed a simulation tool to model the device. Our model is based on combined Particle-In-Cell and Monte-Carlo-Collision (PIC-MCC) approaches which provides a platform for further development and optimization of the device.