Porous silicon membrane

The invention provides a porous membrane (100), wherein the membrane (100) comprises a silicon comprising layer (110) having a first side (101) and a second side (102), wherein a distance between the first side (101) and the second side (102) defines a thickness (dmem) of the membrane (100), Wherein (i) the membrane comprises pores (140), the pores (140) defining open fluid channels from the first side (101) to the second side (102), (ii) a porosity of 10 the membrane (100) is in the range 1-10%, (iii) a mean pore cross-sectional dimension (dp) equal to or less than 10 um, (iv) the membrane thickness (dmem) is equal to or less than 200 um, and (V) the membrane comprises a first layer (121) arranged at the first side (101) and a second layer (122) arranged at the second side (102), wherein the first layer (121) is electrically conductive and the second layer (122) is electrically conductive, wherein the first layer (121) 15 directly contacts the silicon comprising layer (110), and the second layer (122) directly contacts the silicon comprising layer (110).