The surface properties of InGaN play a key role determining the stability and the overall efficiency of the photoelectrochemical devices. This work is devoted to analyze the electrochemical stability in liquid environments and charge transfer characteristics across the n-InGaN/liquid interface in order to build a knowledge base for future consideration on the application of InGaN electrodes in water splitting systems. In addition, novel 3D-microstructured photoanodes are also addressed because of their interesting properties that can be exploited to realize efficient devices.