Van der Waals heterojunctions are extended to semiconducting p-type single-walled carbon nanotube (s-SWCNT) and n-type film that can be solution-processed with high spatial uniformity at the wafer scale. The resulting large-area, low-voltage p-n heterojunctions can exhibit anti-ambipolar transfer characteristics with high on/off ratios. The charge transport can be efficiently utilized in analog circuits such as frequency doublers and keying circuits that are widely used, for example, in telecommunication and wireless data transmission technologies.