Tarekuzzaman Md, Ishraq Mohammad Hasin, Parves Md Shahazan, Rayhan M A, Ahmad Sohail, Rasheduzzaman Md, Al Mamun K A, Hossen M Moazzam, Hasan Md Zahid
Materials Research and Simulation Lab, Department of Electrical and Electronic Engineering, International Islamic University Chittagong, Kumira, Chittagong 4318, Bangladesh.
Department of Electrical and Electronic Engineering, International Islamic University Chittagong, Kumira, Chittagong 4318, Bangladesh.
Phys Chem Chem Phys. 2024 Nov 7;26(43):27704-27734. doi: 10.1039/d4cp02974g.
Potassium germanium chloride (KGeCl) has emerged as a promising contender for use as an absorber material for lead-free perovskite solar cells (PSCs), offering significant potential in this domain. In this study, we conducted a density functional theory (DFT) investigation to analyze and assess the structural, electronic, thermomechanical, and optical characteristics of the cubic KGeCl absorber. The positive phonon dispersion curve confirmed the dynamical stability of KGeCl. The elastic constant satisfied the Born criteria, validating the mechanical stability and ductility of solid KGeCl. The electronic band structure and density of states (DOS) confirmed that the KGeCl material is a semiconductor with a direct band gap of 0.754 eV (GGA) and 0.803 eV (mGGA-RSCAN). The study identified key optical parameters, including absorption, conductivity, reflectivity, dielectric function, refractive index, and loss function, revealing the potential suitability of KGeCl for solar applications. The Helmholtz free energy (), internal energy (), entropy (), and specific heat capacity () are computed based on the phonon density of states. Additionally, we investigated twenty-four configurations comprising different combinations of electron transport layers (ETLs) and hole transport layers (HTLs) in SCAPS-1D software. For this purpose, ETLs such as Ws, ZnSe, PCBM, and C and HTLs such as CBTS, CdTe, CFTS, CuO, P3HT, and PEDOT:PSS are employed. The highlighted structure, ITO/CBTS/KGeCl/Ws/Ni, demonstrates remarkable performance with an efficiency of 22.01%, a of 0.6799 V, a of 41.439 mA cm, and a FF of 78.12%. To analyze photovoltaic (PV) performance, we chose the top four solar cell (SC) configurations. Moreover, a comprehensive examination was conducted to assess the impact of various factors, including the thickness of different layers, capacitance, Mott-Schottky behavior, series and shunt resistance, temperature, and generation-recombination rates, as well as - (current-voltage density) and quantum efficiency (QE) characteristics.
氯化锗钾（KGeCl）已成为用作无铅钙钛矿太阳能电池（PSC）吸收材料的一个有前景的竞争者，在这一领域具有巨大潜力。在本研究中，我们进行了密度泛函理论（DFT）研究，以分析和评估立方晶系KGeCl吸收体的结构、电子、热机械和光学特性。正的声子色散曲线证实了KGeCl的动力学稳定性。弹性常数满足玻恩准则，验证了固态KGeCl的机械稳定性和延展性。电子能带结构和态密度（DOS）证实，KGeCl材料是一种半导体，其直接带隙为0.754 eV（广义梯度近似，GGA）和0.803 eV（改进的广义梯度近似 - 修订扫描校正近似，mGGA - RSCAN）。该研究确定了关键的光学参数，包括吸收、电导率、反射率、介电函数、折射率和损耗函数，揭示了KGeCl在太阳能应用方面的潜在适用性。基于声子态密度计算了亥姆霍兹自由能（）、内能（）、熵（）和比热容（）。此外，我们在SCAPS - 1D软件中研究了由电子传输层（ETL）和空穴传输层（HTL）的不同组合构成的24种结构。为此，采用了诸如Ws、ZnSe、PCBM和C等ETL以及诸如CBTS、CdTe、CFTS、CuO、P3HT和PEDOT:PSS等HTL。突出的结构ITO/CBTS/KGeCl/Ws/Ni表现出卓越的性能，效率为22.0—— ，开路电压为0.6799 V，短路电流密度为41.439 mA cm，填充因子为78.12%。为了分析光伏（PV）性能，我们选择了前四种太阳能电池（SC）结构。此外，还进行了全面检查，以评估各种因素的影响，包括不同层的厚度、电容、莫特 - 肖特基行为、串联和并联电阻、温度以及产生 - 复合率，以及电流 - 电压密度（ - ）和量子效率（QE）特性。
