Semiconductor electrodes. 43. The effect of light intensity and iodine doping on the stabilization of n-silicon by phthalocyanine films

Abstract

The stability of n-Si vacuum-coated with metal-free phthalocyanine (H2Pc) and copper phthalocyanine (CuPc) was studied as a function of the light intensity and redox couple in aqueous solutions. Although the photocurrent at an n-Si coated with H2Pc or CuPc decayed slowly at low light intentsities (1 mW/cm1 2), photopassivation was rapid at higher light intensities (100 mW/cm2). The magnitude of photocurrent and the inhibition of photocorrosion depended upon the solution conditions. Addition of iodine, which is a dopant for the Pc layer, led to larger photoeffects and a lower rate of photopassivation, although the electrode was still unstable after longer irradiation times. Further improvement in stability was observed in the presence of the highly concentrated electrolyte, 11 M LiCl.

Boosting the Performance of WO3/n‐Si Heterostructures for Photoelectrochemical Water Splitting: from the Role of Si to Interface Engineering

“…In addition, Si has a moderate band gap (1.1 eV), and a light absorption that matches the solar spectrum reasonably well [16] . On the down side, Si has a poor chemical stability, because it is rapidly oxidized in aqueous solution under solar illumination or under anodic bias [17] . Covering a Si substrate with a metal oxide film improves the chemical stability and offers a promising model for PEC electrode design.…”

Metallophthalocyanine-based molecular materials as catalysts for electrochemical reactions

“…They can act as spectroscopic sensitizers deposited on semiconductor electrodes [169][170][171][172][173][174][175][176][177][178][179][180][181][182][183][184][185][186][187][188] and can have applications in solar energy conversion devices. The colour of phthalocyanines is modified when they undergo oxidation state changes involving the ligand and this can have applications in electrochromic devices [189][190][191].…”

Cellules photoélectrochimiques de phtalocyanine d'hydroxyaluminium déposées par rotation

“…Des progres remarquables ont CtC rCalisCs dans l'augmentation de I'efficacitC de conversion des cellules photovoltai'ques organiques, passant de au debut des annCes 1970 1% actuellement (3). Les composCs de type phtalocyanine ont r e p une attention particuliere en tant que colorants pour la sensibilisation spectrale et la stabilisation de semiconducteurs inorganiques (4)(5)(6)(7)(8)(9) et en tant que semiconducteurs formant des jonctions liquides avec des couples redox (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25).…”