Q: Let in earlier instance the diode is silicon diode & draw its output.

SOLUTION:    

The diode shall be on for the -ve half cycle. By apply I_d=0 ,V_d = 0.7 to obtain transition voltage

                                                            V_i + V_T - V =0

                                                                          V_i = V - V_T

                                                                            = 4 - 0.7 = 3.3 Volts

3.3 is the transition voltage shall be 4V, therefore for positive half cycle

                                                            V_L = V₀

                                                            V₀ = 16Volts