Cu2O quantum dots modified α-Ga2O3 nanorod arrays as a heterojunction for improved sensitivity of self-powered photoelectrochemical detectors

Flexible and Self-Powered Solar-Blind UV Photodetector Based on the Ti/α-Ga2O3/Electrolyte Heterojunction with High Stability

“…When the semiconductor with chemical potential difference comes into contact with the electrolyte, the electrons will move from the high direction to the low direction with the chemical potential and finally reach the chemical potential balance. 31,36 Figure 8a shows a simple structure diagram of the Ga 2 O 3 solar-blind UV photodetector. Because the work function of titanium is greater than the work function of α-Ga 2 O 3 and the Fermi level of α-Ga 2 O 3 is higher than the redox potential of the Na 2 SO 4 solution, 38 the band bending will occur in the interfaces as shown in Figure 8b.…”

“…On the semiconductor side, the electron chemical potential is given by the work function of the semiconductor, while on the electrolyte side, the electron chemical potential is given by the REDOX potential in the electrolyte. When the semiconductor with chemical potential difference comes into contact with the electrolyte, the electrons will move from the high direction to the low direction with the chemical potential and finally reach the chemical potential balance. , …”

“…A small part of the holes will move to the Ti/Ga 2 O 3 contact surface and be trapped by defects such as oxygen vacancies on the Ti substrate, resulting in a decrease of the Schottky barrier . The other part of the hole will drift into the electrolyte and oxidize the OH – in the captured electrolyte to OH*­(h + + OH – = OH*), while the photogenerated electrons will diffuse to the Ti substrate and reach the Pt electrode through the external circuit to reduce the OH* in the electrolyte to OH – (e – + OH* = OH – ), thereby achieving self-powered detection. , In this work, the Ti sheet not only provides a flexible substrate but also acts as a transport channel for carriers, which can accelerate transport.…”

“…The optical response test of the sample was performed using a CHI 760E electrochemical workstation, which was also reported in our previous work. 31 The 0.5 M Na 2 SO 4 solution was used as the Table 1. Amount of Seed Layers for the Prepared Samples electrolyte.…”

“…The chemical state and oxidation composition of the samples were analyzed by X-ray photoelectron spectroscopy (XPS, ESCALAB 250 Xi, Thermo Fisher). The optical response test of the sample was performed using a CHI 760E electrochemical workstation, which was also reported in our previous work . The 0.5 M Na 2 SO 4 solution was used as the electrolyte.…”