## 3 Effect of Tension and Compression
### Results and Discussion
However, the opposite situation could be considered to exist; that is, an adjacent electron and hole (\"A\" in Figure 13b) moved closer to each other due to reduced deformation transverse to the direction of tension. Therefore, the voltage and electric current potentially increased once. Figure 11: Effects of compression and tension on the electric current as built-in electricity and photoelectricity: (**a**) as built-in electricity, under compression; (**b**) as photoelectricity, under compression; (**c**) as built-in electricity, under tension; (**d**) as photoelectricity, under tension. Figure 12: Effects of compression and tension on the electrical resistance as built-in electricity and photoelectricity: (**a**) as built-in electricity, under compression; (**b**) as photoelectricity, under compression; (**c**) as built-in electricity, under tension; (**d**) as photoelectricity, under tension. Next, we investigated the effects of a TiO\({}_{2}\) catalyst on built-in electricity and photoelectricity under compression and tension, as shown in Figures 14-17. Here, the MCF rubber contained 2, 4, or 5 g of TiO\({}_{2}\), 6 g of Ni, 4.5 g of MF, and 9 g of NR latex. As in Figures 10-12, the tension remained constant under compression, and the pressure remained constant under tension. Changes due to compression or tension are shown as differences from the initial state (with neither compression nor tension). Figure 14: _Cont._  
Figure 13: Model of the effects of compression and tension on the photoelectricity created by electrons and holes emerging from neutral particles and molecules (Figure 5) and on the built-in electricity created by ionized particles and molecules after the emergence of electrons and holes: (**a**) by compression; (**b**) by tension. Figure 14: Effects of compression on the electric current as built-in electricity: (**a**) at 2 g of TiO\({}_{2}\); (**b**) at 4 g of TiO\({}_{2}\); (**c**) at 5 g of TiO\({}_{2}\). Figure 15: Effects of compression on the electric current as photoelectricity: (**a**) at 2 g of TiO\({}_{2}\); (**b**) at 4 g of TiO\({}_{2}\); (**c**) at 5 g of TiO\({}_{2}\). Figure 16: Effects of tension on the electric current as built-in electricity: (**a**) at 2 g of TiO\({}_{2}\); (**b**) at 4 g of TiO\({}_{2}\); (**c**) at 5 g of TiO\({}_{2}\). Figure 17: _Cont._  
Under compression, the built-in current tended to show values that changed from positive to negative as TiO\({}_{2}\) increased, while, in the case of photocurrent, negative values tended to decrease as TiO\({}_{2}\) increased. These results indicate that the enhancement of TiO\({}_{2}\) reduced the built-in current and photocurrent by compression. This can be explained by the model in Figure 13a, where ionized particles increased with increasing TiO\({}_{2}\), and the adjacent ionized particles approached each other and became contiguous such that the voltage and electric current became zero due to compression. On the other hand, under tension, built-in current tended to show values that changed from negative to positive as TiO\({}_{2}\) increased, while positive photocurrent values tended to decrease to zero with increasing TiO\({}_{2}\). These results indicate that the enhancement of TiO\({}_{2}\) increased built-in current values but decreased photocurrent values due to tension. This can be explained by the model in Figure 13b, where the adjacent ionized electron and hole (\"A\" of built-in electricity in Figure 13b) approached each other due to the reduced deformation under tension such that the voltage and electric current were enhanced; however, the adjacent electrons and holes that emerged from neutral particles and molecules (\"A\" of photoelectricity in Figure 13b) approached each other such that the voltage and electric current became zero due to tension.