n electron transporting  and hole-blocking  layer (ETL)  between  the fluorine-doped  tin oxide  (FTO)  and mesoporous  titanium  dioxide  interface  of photoanode  is essential  in dye-sensitized  solar cells (DSCs)  for improving  their photovoltaic  performance.  In the present  work,  we have examined  the potential  for further  improving  device  performance  by using  alternative  materials  for ETLs.  Accordingly,  the effect  of   placing  TiO₂  based  ETLs  with spin coated  ultra-thin  transition  metal  oxides  (TMOs),  molybdenum  trioxide  (MoO₃) and tungsten  trioxide  (WO3 ) films has been studied.  TMO films of 10 nm thickness  have been found  to be optimal  for obtaining  good  transparency  and  charge  transport  properties,  without  compromising  device  performance.  Further,  devices  fabricated  with surfactant  assisted  (SA-)  MoO₃ ETLs have shown efficiency  ~4%,  which  is comparable  with devices  based  on conventionally  prepared  TiO2  ETLs.  In addition,  a significant improvement  in efficiency  (15%)  has been observed  for DSCs  prepared  using  SA-WO₃  films.  The overall improvement  in device  efficiency  is  attributed  to the increase  in short-circuit  current  density  without  loss of open circuit  potential  and fill factor.  Detailed  analyses  of results  suggest  that in  ddition  to surface  morphology,  transparency  and charge  transport  properties;  oxygen  vacancies  in sub-stoichiometric  TMOs also plays an important  role in determining  the device  performance.  The findings reveal  that TMOs  have significant  potential  to replace  TiO 2  ETL in DSCs  and other  third generation  solar cell, viz. perovskite  and polymer  solar cells.