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The photoinduced stiffening (PIS) and photoplastic effect (PPE) of ZnS individual nanobelt (NB) were observed by using a nanoindenter in conjunction with an incident ultraviolet (UV) light source system. The results show that the elastic modulus and hardness of ZnS individual NB under UV illumination are at least 32% and 20% larger than those in darkness. The mechanisms of PIS and PPE are interpreted by the increase in electronic strain and Peierls barrier due to the photogeneration of free carriers in ZnS individual NB. The research may offer useful guidelines to the application of optoelectronic devices based on individual nanostructures.

Under the excitation of ultraviolet, X-ray, and mechanical stress, intense orange luminescence (Mn 2+ , 4 T 1 → 6 A 1) can be generated in Mn 2+-doped SrZn 2 S 2 O crystal in orthorhombic space group of Pmn2 1. Herein, the multiple energy conversion in SrZn 2 S 2 O:Mn 2+ , that is, photoluminescence (PL), X-ray-induced luminescence, and mechanoluminescence, is investigated. Insight in luminescence mechanisms is gained by evaluating the Mn 2+ concentration effects. Under the excitation of metal-to-ligand charge-transfer transition, the most intense PL is obtained. X-ray-induced luminescence shows similar features with PL excited by band edge UV absorption due to the same valence band to conduction band transition nature. Benefiting much from trap levels introduced by Mn 2+ impurities, the quenching behavior mechanoluminescence is more like the directly excited PL from Mn 2+ d-d transitions. Interestingly, this concentration preference leads to varying degrees of spectral redshift in each mode luminescence. Further, SrZn 2 S 2 O:Mn 2+ exhibits a good linear response to the excitation power, which makes it potential candidates for applications in X-ray radiation detection and mechanical stress sensing.

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