Device comprising positive hole injection transport layer, method for producing the same and ink for forming positive hole injection transport layer

A method for producing a device comprising a substrate, two or more electrodes facing each other disposed on the substrate and a positive hole injection transport layer disposed between two electrodes among the two or more electrodes comprising:

• a preparation step of preparing an ink for forming a positive hole injection transport layer containing a transition metal-containing nanoparticle containing a transition metal and/or transition metal compound and a protecting agent, and an organic solvent;
• a formation step of forming the positive hole injection transport layer on any of layers on the electrodes using the ink for forming the positive hole injection transport layer;
• and
• an oxidation step of oxidizing at least a part of the transition metal and/or transition metal compound in the transition metal-containing nanoparticle to produce a transition metal oxide;
• wherein the protecting agent in the transition metal-containing nanoparticle contains at least one kind selected from the group consisting of an alkyl group, an aromatic hydrocarbon and a heterocyclic ring, and a linking group which functions to connect the transition metal and/or transition metal compound;
• and
• wherein the linking group is one or more kinds selected from functional groups represented by the following formulae (1a) to (1l):
• wherein each of Z1, Z2 and Z3 independently represents a halogen atom or an alkoxy group.