Membraneless Microfluidic Paper Fuel Cells (MMPFCs) are promising devices to harvest energy for various portable applications. This is primarily because such devices eliminate the need for membrane, and external pumps due to the built-in co-laminar flow, and embedded capillaries, respectively. However, these devices have enormous scope to optimize their performance. Herein, investigations on MMPFC have been carried out with varying electrode separation, whereby cellulose papers acts as the microchannel of MMPFC. Here, various grades of carbon-supported graphite pencils serve as electrodes, formic acid acts as a fuel, and sulphuric acid works as an electrolyte. Oxygen from the atmospheric air acts as an oxidant for ionic exchange under co-laminar flow in the MMPFC. These MMPFCs with the optimized configuration provide enhanced energy densities with different grades of the microchannel material along with variation in electrode separation. Leveraging grade 1 Whatman cellulose paper as MMPFC microchannel with 1 mm electrode separation, the MMPFC generates energy with a maximum open-circuit potential of 0.49 V, a maximum current density of 2.45 mAcm⁻² and power density of 0.26 mWcm⁻².

无膜微流体纸燃料电池（MMPFC）是为各种便携式应用收集能量的有前途的设备。这主要是因为这样的设备分别消除了对膜的需求，以及由于内置的​​共层流和嵌入式毛细管，因此无需外部泵。但是，这些设备具有优化其性能的巨大范围。在本文中，已经通过改变电极间距进行了MMPFC的研究，从而纤维素纸充当MMPFC的微通道。在此，各种等级的碳负载石墨铅笔用作电极，甲酸用作燃料，硫酸用作电解质。在MMPFC中的层流下，来自大气中的氧气充当离子交换的氧化剂。这些具有优化配置的MMPFC在不同等级的微通道材料以及电极间距变化的情况下提供了增强的能量密度。利用1级Whatman纤维素纸作为MMPFC微通道，电极间距为1 mm，MMPFC产生的能量最大开路电势为0.49 V，最大电流密度为2.45 mAcm^-2和功率密度为0.26 mWcm ^-2。