Lateral-tandem organic photovoltaic cells with carrier transport and generation layers

We report the fabrication and operation of organic photovoltaic cells with lateral junctions and separated carrier-generating and carrier-transporting layers. Significant photocurrent increase was observed by inserting carrier generating layer having strong visible absorption. For the lateral tandem cells, an increase in the number of unit cells increased the photocurrent while keeping the photovoltage constant. It is easier to increase the number of unit cells in lateral tandem cells compared to conventional vertical tandem cells because the adjustment of photocurrent density flowing in each unit cell is no longer necessary.