Inverted organic solar cells using nanocellulose as substrate

Organic photovoltaics (OPVs) offer the potential for ultralow cost mass-producible photovoltaic devices. Other advantages are light weight and good mechanical flexibility. To further reduce the cost, the replacement of the conventional conducting substrates for cellulose is an interesting choice. There are three main types of nanocellulose materials: nanofibrillated cellulose (NFC), nanocrystalline cellulose (CNC), and bacterial nanocellulose. In this work, the synthesis of two types of nanocellulose substrates and their application in OPVs were achieved. For the first time, the different properties of the cellulose substrates and their influence on the OPV performance were addressed. The nanocellulose substrates CNC and NFC were characterized by XRD, AFM, and DSC. CNC films were more homogeneous, smoother, crystalline and with low roughness. Thus, when comparing the cellulosic substrates, the best device the one based on CNC. The PCE values of the inverted OPV cells were 3.0, 1.4, and 0.5% on to glass, CNC and NFC substrates.