Heterostructure materials are increasingly utilized in solar energy conversion to pursue high efficiency and longterm stability. The charge transfer across interfaces gives rise to major energy loss arising from non-ideal interfacial effects, i.e., high interfacial energy barrier and low interfacial contacting area. Herein, we demonstrate a facile interface engineering strategy to eliminate non-ideal interfacial effects. A heterojunction of CN@CP25 is constructed via polyphenol-assisted assembly of titania (P25) and carbon nitride (CN). The uniform dispersion of P25 on CN enlarges the interfacial contacting area of 3.2-fold compared with random dispersion, while the transformation of polyphenols into conjugated carbon facilitates the interfacial charge transfer by switching a 0.4 eV Schottky contact to a 0.1 eV Ohmic contact between CN and P25. A 2.5-fold enhancement of charge transfer flux is obtained with an initial reaction rate of 5185 mu mol h-1 g-1 for photocatalytic nicotinamide regeneration.