Light-receiving device and light-emitting and light-receiving apparatus

A light-receiving device comprising:

• a light-receiving layer between a pair of electrodes,
• wherein the light-receiving layer comprises an active layer, a buffer layer, and an electron-transport layer,
• wherein the buffer layer is between the active layer and the electron-transport layer and is in contact with the active layer, and
• wherein the buffer layer comprises a heteroaromatic compound comprising a plurality of cyano groups.

A light-receiving device comprising:

• a light-receiving layer between a pair of electrodes,
• wherein the light-receiving layer comprises an active layer, a buffer layer, and an electron-transport layer,
• wherein the buffer layer is between the active layer and the electron-transport layer and is in contact with the active layer,
• wherein the active layer comprises a first organic compound,
• wherein the buffer layer comprises a second organic compound,
• wherein the electron-transport layer comprises a third organic compound, and
• wherein a LUMO level of the second organic compound is higher than a LUMO level of the first organic compound and is lower than a LUMO level of the third organic compound.