Kawya J, Durairaj M, Anandan S, Sabari Girisun T C
Nanophotonics Laboratory, Department of Physics, Bharathidasan University, Tiruchirappalli, India.
Nanomaterials and Solar Energy Conversion Laboratory, Department of Chemistry, National Institute of Technology, Tiruchirappalli, India.
Front Chem. 2025 Jan 15;12:1511600. doi: 10.3389/fchem.2024.1511600. eCollection 2024.
An interesting approach of including an upconverter in the MoS counter electrode can yield broadband light harvesting Pt-free DSSC assembly. Here different upconverter (UC) nanoparticles (Yb, Er incorporated NaYF, YF, CeO & YO) were synthesized and loaded in MoS thin film by hydrothermal method. The inclusion of UCs in MoS films exposed without any secondary formation of upconverters and the uniform deposition of the films are confirmed through XRD and FESEM analysis respectively. The absorption spectrum (UV-Vis-NIR) confirms the increase in absorption intensity in visible and NIR regions due to the incorporation of UCs. Under 980 nm excitation, the UCs-loaded MoS films show emission in blue (450-490 nm), green (520-540 nm) and red (600-700 nm) regions due to the f-f inner transition occurring in the Er ions. The oxide and fluoride UCs-based DSSCs were fabricated with an FTO/TiO/N719/Triiodide electrolyte/UC@MoS/FTO assembly. Oxide UCs show greater electrocatalytic activity, which might be owed to the films exposed with more catalytic active sites favourable for ion transportation in the I/I electrolyte. Among them, higher photoconversion efficiency (PCE) of 7.1% was witnessed for (YO: Er, Yb) @MoS counter electrode-based DSSC which is due to the good conductivity (R) of the film, the longer electron lifetime and photon harvesting enhancement by upconversion process. It is notably convinced that the UC-loaded MoS films can be used as an effective counter electrode for the possible realization of upconverter DSSC and used for broadband light absorption.
一种有趣的方法是在二硫化钼对电极中加入上转换材料，从而得到无铂的宽带光捕获染料敏化太阳能电池组件。这里合成了不同的上转换纳米颗粒（掺镱、铒的氟化钠钇、氟化钇、氧化铈和氧化钇），并通过水热法将其负载在二硫化钼薄膜中。通过X射线衍射和场发射扫描电子显微镜分析分别证实了在二硫化钼薄膜中加入上转换材料后没有上转换材料的二次形成，以及薄膜的均匀沉积。吸收光谱（紫外-可见-近红外）证实，由于加入了上转换材料，可见光和近红外区域的吸收强度增加。在980纳米激发下，由于铒离子中发生f-f内转换，负载上转换材料的二硫化钼薄膜在蓝色（450-490纳米）、绿色（520-540纳米）和红色（600-700纳米）区域发光。基于氧化镧和氟化镧上转换材料的染料敏化太阳能电池采用FTO/TiO/N719/三碘化物电解质/上转换材料@二硫化钼/FTO组件制备。氧化镧上转换材料显示出更高的电催化活性，这可能是由于薄膜暴露了更多有利于碘/碘化物电解质中离子传输的催化活性位点。其中，基于（氧化钇：铒，镱）@二硫化钼对电极的染料敏化太阳能电池的光转换效率（PCE）高达7.1%，这归因于薄膜良好的导电性（R）、更长的电子寿命以及上转换过程增强的光子捕获能力。值得注意的是，负载上转换材料的二硫化钼薄膜可以用作有效的对电极，以实现上转换染料敏化太阳能电池，并用于宽带光吸收。
