iText = "маЗуриков ПетР пЕТровиЧ"
iProperText = StrConv(iText, vbProperCase) ' Or
iProperText = StrConv(iText, 3) ' Вариант I.
iProperText = Application.Proper(iText)
iProperText = WorksheetFunction.Proper(iText)
iProperText = Excel.Application.Proper(iText)
iProperText = Excel.WorksheetFunction.Proper(iText)
iProperText = Application.WorksheetFunction.Proper(iText) ' Вариант II.