A-site-deficient Y, Cr doubly doped SrTiO₃ ((Y_0.08Sr_0.92)_1-xTi_0.8Cr_0.2O_3−δ (x = 0.01, 0.03, 0.05)) powders were synthesized via sol–gel method, followed by sintering at 1450 °C at ambient condition. The phase composition, mixed conductivities, and sensing performance are characterized to identify the influence of A-site deficiency on the Y- and Cr-doubly doped SrTiO₃. The ionic conductivity and total conductivity of (Y_0.08Sr_0.92)_1-xTi_0.8Cr_0.2O_3−δ clearly increase and decrease upon an increase in the A-site deficiency, respectively. The enlarged saddle point and decreased relaxation time are responsible for the augmentation of ionic conductivity. The oxygen sensor with (Y_0.08Sr_0.92)_1-xTi_0.8Cr_0.2O_3−δ dense diffusion layer show superior sensing performance with A-site deficiency level increasing. The relationship between logI_L and 1000/T is obtained and the charge compensation mechanism is systematically discussed. The obtained results demonstrated that limiting current is nearly independent of temperature at high operating temperature. This paper provides a chemical strategy to enhance the mixed conductivity of oxygen sensors through Y- and Cr-double doping and via a simple, low cost, and traditional sol–gel technique.

通过溶胶-凝胶法合成了A位缺陷的Y，Cr双掺杂SrTiO ₃（（Y _0.08 Sr _0.92）_{1- x} Ti _0.8 Cr _0.2 O3 _-δ（x = 0.01，0.03，0.05））粉末，然后通过在环境条件下在1450°C下烧结。表征相组成，混合电导率和传感性能，以确定A位缺陷对Y和Cr双掺杂SrTiO _3的影响。（Y _0.08 Sr _0.92）_1-x Ti _0.8 Cr _0.2 O3 _-δ的离子电导率和总电导率明显地随着A位缺陷的增加而增加和减少。增大的鞍点和减少的弛豫时间是导致离子电导率增加的原因。具有（Y _0.08 Sr _0.92）_1-x Ti _0.8 Cr _0.2 O3 _-δ致密扩散层的氧传感器显示出优异的感测性能，且A位缺陷水平增加。log I _L与1000 / T之间的关系获得了电荷，并系统地讨论了电荷补偿机制。获得的结果表明，在高工作温度下，极限电流几乎与温度无关。本文提供了一种化学策略，可通过Y和Cr双掺杂以及通过简单，低成本和传统的溶胶-凝胶技术来增强氧气传感器的混合电导率。